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A study was designed to develop a measure of both acute and chronic effects of THC administration on memory in the rat. Errors in an 8-arm radial maze, before and after two delay intervals (5 s and 1 h, introduced between the fourth and the fifth arm choice), constituted the principal dependent measures. The first experiment involved testing the animals shortly after administration of 1.25 mg/kg THC. The drug did not affect performance in the pre-delay tests, although a significant effect was observed after the 5-s delay but not after 1-h delay. In the second experiment, 5 mg/kg THC or saline were administered 6 days/week for 90 days. Testing was conducted 18 h after each drug administration. During chronic administration the pre-delay performance did not differ between groups but the post-delay performance of the THC group deteriorated in a gradual manner, relative to their controls, in both the 5-s and 1-h delay conditions. After discontinuation of drug administration, the differences between groups reversed only after 30 days. The results provided evidence that both acute and chronic administration of THC affected working-memory in the radial arm maze test, although it did not interfere with the general cues of the task (reference memory). Chronic drug effects on memory were reversible after prolonged abstinence. Thus, the 8-arm radial maze task proved to be a useful measure of THC effects on memory and could be further used to investigate more thoroughly the mechanisms involved in such drug effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Interviews were conducted with 59 former intensive users of illicit drugs with no evidence of current social or behavioural dysfunction. Data were gathered by in-depth standardized interviews through which, past and current psychoactive substance use (including alcohol, tobacco and tranquillizers) were assessed. Special attention was given to the subjects' attributions as to what had caused the change in the drug use pattern. Events attributed for ending or substantially decreasing drug use were categorized as follows: 'physical-mental problems/disliked side effects' (27.1% of respondents), 'developmental/maturational/existential reasons' (27.1%), 'formal or informal drug treatment system' (11.8%), 'interpersonal reasons' (10.2%), 'job or school/performance lowering' (10.2%), 'religious/spiritual involvement' (6.8%), and 'legal/financial problems' (6.8%). The major finding was that only 7 out of the 59 respondents (11.8%) reported having ever been in any formal or informal drug treatment system.

The effects of chronic ethanol administration were studied in rats receiving amygdaloid kindling. Daily ethanol administration 10 min prior to kindling stimulation delayed acquisition of kindling without affecting the electrical afterdischarge. For the lowest tested dose of ethanol (0.5 g/kg), this delay was restricted to kindling stages 1 and 2. For the higher doses of ethanol (1.0 and 1.5 g/kg) this delay became more severe and stages 3 and 4 were blocked. Ethanol produced a clear dose-related anticonvulsant effect upon kindled seizures. After repeated exposure to kindling stimulation and ethanol this anticonvulsant effect vanished. After a 15-day interval without stimulation or ethanol application kindled animals were insensitive to ethanol's anticonvulsant effect. In conclusion, it is suggested that the anticonvulsant effects of low ethanol doses are restricted to kindling stages 1 and 2 and that anticonvulsant effects of high ethanol doses are limited by tolerance and by the level of consolidation of the kindled seizure. Finally, we suggest that the anticonvulsant properties of ethanol are not due to its general depressant effect but to some rather specific action.

The Short-Alcohol Dependence Data (SADD) and the Alcohol Dependence Scale (ADS) questionnaires, both designed to evaluate the degree of severity of alcohol dependence, were compared in a sample of 201 known alcoholics. Although a significant correlation was found between the scores obtained on the two scales (r = 0.61; P less than 0.01), respondents were classified differently by the two questionnaires (Kappa = 0.20). Subjects were generally considered less dependent by the ADS than by the SADD. Different possibilities that could explain the differential classification are discussed.

An experiment was designed to predict the outcome of establishing a worker-parasite relationship between rats paired in a modified Skinner box with the water dipper and the bar attached to opposite walls. The rats were first trained individually to press the bar for water reward. After this individual training the reinforcement, besides being contingent to the pressing response, began also to be freely delivered (by the experimenter) in a variable-interval schedule of reinforcement. The number of such sessions each animal took to stop emitting the bar-pressing response was recorded. After stopping the operant response the animals were again trained individually. Following that they were paired in the experimental cage according to the number of sessions they took to stop the bar-press response. After the development of the worker-parasite relationship, categorization into workers and parasites could be predicted according to the number of sessions the rats took to stop the response in the individual condition. Individual characteristics may then play a role, among a multitude of other possible variables, in the outcome of the worker-parasite relationship between rats.

Summary The possibility of applying the short-form Alcohol Dependence Data questionnaire (SADD) to an interview situation was tested in an alcoholic sample. This was in contrast to using the self-completion questionnaire as was originally proposed. The correlation between the SADD, when applied to an interview situation and the SADD, when used as a self-completion questionnaire, as evaluated by the Spearman correlation coefficient, was r= 0.81. A test-retest reliability using the self-completed form provided a correlation of r= 0.90. Split-half reliability obtained far both the interview and self-completion questionnaire yielded correlations of r= 0.88 and r= 0.82 respectively. The interview version of the SADD can, therefore, be utilised with illiterate subjects. Furthermore, it has provided data showing that the SADD clearly discriminated between a sample of normal volunteers (n= 55) and a sample of alcoholics (n= 50).

The present paper analyses the alterations in sensitivity, specificity and in the positive predictive value (PPV) of GGT as a state marker of alcohol abuse when used either alone or in combination with glutamate pyruvate transaminases (SGPT), glutamate oxalacetate (SGOT) and mean corpuscular volume (MCV). The results obtained with an alcoholic ( n = 70) and non-alcoholic sample ( n = 63) showed that the best combination considering sensitiviy was obtained when GGT was combined with MCV (80%). However, this combination produced the largest decrease in PPV. The relevance of taking into account not only sensitivity but also PPV when the markers are to be used as screening tests in unselected populations is discussed.

Fourteen female rats competed for food in a straight runway against 14 male rats through a fixed-pair procedure. Confirming our previous results, the females won only 24 and 30%, respectively, in two experimental sessions of five contests each. The other 15 females were given 1.0 mg/kg of apomorphine 10 min before the beginning of the contest session, while their 15 male partners received saline. Under drug action females won 65% of the contests. Forty-eight hours later, the same females, which now received control solution, won only 15%.

Gamma glutamyl transferase (gamma GT) and mean corpuscular volume (MCV) were evaluated in 58 alcoholics entering alcoholism treatment. The same patients were reassessed after one month of abstinence. Group results revealed a significant reduction of gamma GT from 80.2 to 43.1 IU/l while no alteration was detected for MCV (from 97.1 to 96.7 mu 3). However, individual analysis showed that the average MCV results obtained from the 2nd evaluation masked important within-individual differences. Thus, although a considerable percentage of alcoholics with initial high values showed an improvement, 44% of those with initial normal results had abnormally high reevaluation values. Limitations of serial MCV measurement during alcoholism treatment follow-up are discussed in light of these data.

Three experiments were performed in an attempt to prevent the worker—parasite relationship which develops when pairs of rats are placed in a Skinner box with the water dipper and the bar attached to opposite walls. In this situation, one of the rats performs most of the bar presses (worker rat) while the partner receives the rewards without working (parasite rat). In the first experiment, it was shown that the availability of one lever and one water dipper for each rat did not prevent the worker—parasite relationship, although it increased the chances of the worker rat to obtain the reward. In the second experiment, besides each rat being provided with one bar and one water dipper, they had simultaneous individual training (separated by a transparent division). In this situation, after the division was removed, the worker—parasite relationship also developed. Finally, in the third experiment, it was shown that a worker—parasite relationship developed even when two previous worker rats in the single bar—single water dipper situation were paired in a box where one lever and one water dipper were available for each rat. These data indicate that the worker—parasite relationship develops under conditions that should favor co-active behavior and cannot, therefore, be attributable only to a situational structure that favors it.

Competitive behavior was studied in pairs of rats, under conditions where the whole brain amine levels of one of these rats was manipulated pharmacologically. The test situation employed was a narrow runway in which one rat had to push its partner in order to be rewarded with food. Competition between pairs was not affected by administration of 300 and 600 mg/kg of para-chlorophenylalanine, although these doses caused a 90 percent decrease in brain serotonin levels. A 100 mg/kg dose of tryptophan, which increased brain serotonin level by 36 percent did not alter competition either; dose of 300 and 500 mg/kg of tryptophan induced marked alteration in the behavior of rats, to such an extent that competition did not occur. Fifty, 100 and 200 mg/kg of dihydroxyphenylalanine, administered 50 min before test situation, induced significant increases in winning behavior, either in naive rats or in previously “loser” rats. Forty-eight hr later the winning behavior frequency of these animals returned to values near the chance level of 50 percent. The increase in winning behavior coincided with a significant increase in brain dopamine measured 50 min after the treatment; norepinephrine was not altered. Forty-eight hr later, when the winning frequency was back to normal, brain dopamine levels returned to control values. Twenty-five mg/kg bis (4-methyl-l-homopiperazinyl-thiocarbonyl) disulphide (FLA-63), did not change dopamine level in brain but markedly reduced that of norepinephrine. This dose of FLA-63 induced an increase of winning behavior. α-Methyl-para-tyrosine (150 mg/kg) and 3,α-dimethyltyrosine (100 mg/kg) decreased brain levels of dopamine and norepinephrine but did not alter the competitive behavior of rats. The possibility that dopamine may be involved in this behavioral situation is discussed.

The effects of apomorphine, Dopa and haloperidol on the competitive behavior in a straight runway of genetically selected Winner-Runway rats (WRS rats), Loser-Runway rats (LRS) and non-selected rats were studied. Apomorphine significantly increased the percentage of winning in nonselected rats competing against WRS rats. In another experiment LRS rats which lost 100 percent of the contests against WRS rats, achieved 50–60 percent of wins when under apomorphine or Dopa effects. When retested without drugs they were again defeated. In pairs made up by two nonselected rats, haloperidol blocked the increase of winning induced by apomorphine. Use of the terms winning and losing instead of dominance and submission to describe the competitive behavior of rats in the straight runway is discussed.

Male and female rats were observed in an open field at 30, 45, 60, 90, and 120 days of age. Thirty- and 45-day-old rats of both genders presented similar defecation, ambulation, and rearing scores. From 60 days on the male rats showed higher defecation scores and less ambulation and rearing than did the females. The gender difference observed in the adult rats reflected a decrease of defecation by females and a decrease of ambulation and rearing by males when compared to the earlier ages.

The information on drinking habits contained in medical records with that obtained through the CAGE alcoholism screening test was compared for 124 inpatients of a teaching general hospital. This survey was followed by testing the possibility of introducing the CAGE test into the routine clinical interview. A second analysis of 110 medical records performed 2 months later indicated the failure of this attempt, as the general pattern of information on drinking habits remained unaltered and characterized by either no information at all or information that was too ambiguous to be of clinical value. Among the different hypotheses that could account for the negative results is the possibility that physicians are not sufficiently informed on the wide spectrum of clinical disorders associated to alcohol abuse. Another important factor is the lack of motivation shown by attending physicians to detect less obvious cases of alcohol dependence as they feel pessimistic about dealing with this condition.

When rats are paired in a situation where the reward is contingent on a bar-pressing response, one of the rats performs most of the bar pressing (worker rat), while its partner receives the reward without working (parasite rat). The possible influence of the persistence of a learned response and of the schedule of reinforcement, was studied. No correlation was found between persistence of response and the categorization of the rats as workers or parasites. On the other hand, when rats individually trained in a variable interval (VI) schedule of reinforcement were paired with rats trained under continuous reinforcement (CRF), most, although not all, VI trained animals became workers. This result shows that rats can be induced to behave as workers through the manipulation of the schedule of reinforcement at the individual training.

When previously trained rats are paired in a modified Skinner box, a worker—parasite relationship develops. The characteristics of the fighting episodes which occur during the establishment of this relationship were studied. During the first paired sessions, both rats displayed a similar pattern of aggressive behavior, whereas, at the later sessions, the worker rats were aggressors, and the parasite rats assumed defensive postures. It was concluded that aggression is a consequence and not a determinant of the worker—parasite relationship. In a second experiment, it was observed that pairing two workers induced more aggressive behavior, than when pairing two parasites. This result was explained on the basis of past experience in fighting, determined by the previous role of the rats as workers or parasites.

The interaction of 5 psychoactive drugs (ethanol, chlorpromazine, diazepam, pentobarbital and THC) with a nonpharmacological factor was studied in rats. The nonpharmacological variable studied was the level of motivation to overcome the depressant action of the drugs administered. Rats highly motivated to perform a learned escape response (high intensity footshocks during training) required significantly higher doses of ethanol to become impaired when compared to low motivated animals (low intensity footshocks during training). However, the level of motivation did not interact with the action of the other 4 drugs, as the doses required to impair the escape response were the same in the low and high motivated rats. The greater susceptibility of ethanol to a nonpharmacological factor when compared to the other psychoactive drugs is discussed.

The potential of ethanol-induced hypothermia on the glycemic alterations induced by this drug were evaluated. In Experiment 1 ambient temperature was manipulated. After 4.0 g/kg of ethanol blood glucose levels and body temperature were assessed in fed or 48 hr starved rats at either 21 degrees C or 28 degrees C room temperature. Hyper or hypoglycemia was observed depending on both the feeding condition and the environmental temperature. In Experiment 2, this hypothesis was tested by determining if rats tolerant to the thermic effects of ethanol would show a decreased glycemic response. The results support this assumption.

Seventy-nine undergraduate social drinkers were the subjects in two studies. Both studies had two experimental sessions and followed a blind design. The subjects in experiment I (expectancy manipulation) were informed they would certainly receive an alcoholic beverage in one session, while in the other one they were told the beverage possibly contained alcohol. Thus, the different expectancy on the beverage content was evaluated. The volunteers in experiment II (attention demanding tasks) were submitted to attention tests in one session and in another one they were not. Thus, the assumption that tasks would motivate the subjects to stay more sober and rate themselves as less intoxicated was studied. Each subject received one of three alcohol doses (0.0; 0.4 or 0.6 g/kg): the same dose in both sessions of each experiment. Blood alcohol level (BAL), reaction time, and self-rating intoxication scores were recorded. The variables studied did not alter either BAL or reaction time values. The expectancy manipulation changed the self-rated intoxication with the lower alcohol dose (0.4 g/kg). So when doubt had been raised the subjects rated themselves as less intoxicated. However, this change was only found with a verbal scale. The attention demanding tasks manipulation did not change the self-rating evaluations. It is suggested that the tasks performed were not appropriate to motivate the subjects to stay sober. The differential sensitivity of the self-rating intoxication scales utilized, and the role of alcohol dose in the study of nonpharmacological variables are discussed.

The performance of genetically selected Winner-Runway rats (WRS) and Loser-Runway rats (LRS) in the food-hole competition and in a labor-division situation was studied. The WRS rats won most of the trials when competing with LRS rats in the runway competition, but both groups had a similar performance in the food-hole test, indicating no correlation between the two procedures. When LRS and WRS rats were paired in the labor-division task, the LRS rats performed most of the bar presses (worker rat) while the WRS received the reward almost without working (parasite rat). This result could be due to the higher bar pressing rate showed by LRS rats in the individual training sessions. To study this possibility another experiment was carried out in which twice as much individual training sessions were given. In this experiment, at the last training trials WRS and LRS rats were performing equally. When they were paired, although the results were in the same direction as in the previous experiment, the difference in the categorization in workers and parasites between WRS and LRS rats reached no statistical significance.

The effects of Δ9-THC, chlorpromazine and amylobarbitone on the labor division achieved by rats were studied. While the first two drugs in the doses of, respectively, 5.0 and 3.0 mg/kg, induced an inversion in the social pattern, amylobarbitone was ineffective at doses of 10.0 and 20.0 mg/kg; labor division of rats trained under a CRF was more sensitive to the drugs effects than that of animals under a VI schedule of reinforcement. Results were discussed in terms of a drug induced deconditioning effect without loss of motivation.

The effects of acute and chronic administration of Δ9-THC, cannabis extract and control solution on the behavior of rats repeatedly exposed to an open-field arena have been studied. After the first dose both Δ9-THC and cannabis extract significantly decreased defecation, grooming and rearing; ambulation was not affected. After 20 injections of both marihuana compounds the rats showed values for defecation, grooming and rearing near to those obtained during the predrug phase; control rats, however, showed a significant decrease in these parameters indicating habituation to the open-field. The results are discussed in terms of effects of marihuana on emotional behavior of rats.

Data on the correlation between the degree of severity of the alcohol dependence syndrome, as evaluated through the Short Alcohol Dependence Data (SADD) questionnaire, and alterations of four biological state markers of alcohol abuse, namely gamma-glutamyltransferase (GGT), glutamate pyruvate transaminase (SGPT), glutamate oxalacetate transaminase (SGOT) and mean corpuscular volume (MCV), in a sample of 137 alcoholics, are presented. A significant increase in the proportion of altered GGT and SGOT results was found in those patients with higher scores in the SADD. The analysis of the correlation (Spearman coefficient) between the values of each biological test and the SADD scores showed only a significant, though low, positive correlation for SGOT (r=0.29).

The development of tolerance to the disruptive effects of ethanol on bar-pressing behavior was studied in rats by exposing them to four cycles of drug administration intercalated by 34-day drug-free periods. A negative correlation was obtained between the successive cycles and the number of sessions required for the rats to reach the criterion of tolerance. Also studied was the possible difference in the rate of development of tolerance in the four cycles when ethanol was administered before or after the task. One group of rats was required to perform the response under the influence of ethanol, while other group received the drug 90 min after the bar-pressing sessions. At the first cycle the group which performed under drug action developed tolerance more rapidly than the group which received ethanol after the task.

Male Wistar rats (N = 84) weighing 230-270 g were fasted 48 hr. Equal groups were controls, nephrectomized bilaterally and sham-operated. Equal subgroups were then given 4.0, 6.0 or 7.5 g of alcohol per kg of body weight or water by orogastric intubation. Blood glucose levels did not decrease significantly after nephrectomy alone or after the 4.0 g/kg dose. Blood glucose declined significantly more in the nephrectomized than in the sham-operated rats at 90 and 180 min after the 6.0 g/kg dose. Blood glucose decreased significantly in both the nephrectomized and sham-operated rats after the 7.5 g/kg dose.

Three questions related to ethanol's stimulating effect (ESE) were studied. The first referred to the reported absence of tolerance to ESE in mice. It was determined whether tolerance would develop if the period of ethanol treatment were extended significantly beyond those normally found in the literature. No evidence of tolerance to ESE was found over a 5-month period of treatment. The second issue related to the possibility that mice not only do not develop tolerance but actually become more responsive to ESE after chronic exposure. A dose of ethanol that acutely did not produce a significant activating effect did induce a marked excitation after the animals were chronically treated with ethanol. Finally, the issue was addressed of whether the absence of ESE in some strains of rats could in part be due to a masking effect by the depressant component of this drug. To test this possibility rats were treated with ethanol for a 4-month period. Tolerance to the depressant effect was observed but no ESE was detected.

The open field test used to study behavioral alterations induced by psychotropic drugs is based mainly in the defecation, ambulation, rearing and grooming presented by animals subjected to the test. Because of the criticisms raised against the defecation score as a measure of the central effects of drugs, in the present experiment a modification of the test is proposed for the rat. The main points that characterize the new procedure are: (1) defecation scores are not considered; (2) besides ambulation, rearing and grooming, immobility was also recorded; (3) the total time of observation was increased, and (4) the stimuli, usually presented simultaneously in the open field (light and noise), were presented separately. The results obtained suggest that it is possible to differentiate classes of psychotropic drugs, without taking the defecation and grooming scores into consideration. Besides stimulants that evoked a characteristic pattern of behavior, neuroleptics could be differentiated from anxiolytics. Similarities, according to the dose, between barbiturates and anxiolytics were detected. Under LSD a peculiar pattern of behavior characterized by a large reactivity to light was observed.

This study examined the effect of footshock administered at different ages on the later runway-competitive behavior of rats. Rats shocked either on days 5–14, 15–24, or 25–34 did not show alterations compared to control animals when tested at 90 days of age in runway-competitive behavior. However, when shock treatment was administered either on days 35–44, 45–54 or 105–114 it increased runway-victories measured 40–70 days after the shock experience. This increase was observed when shocked rats competed either against handled or non manipulated controls. In a second series of experiments, effect of footshock experience in modification of the chances of winning in genetically selected Loser-Runway rats (LRS rats) when competing against genetically selected Winner-Runway rats (WRS rats) was tested. In these experiments, LRS rats were shocked on days 35–45 and runway competition took place on day 90. In control experiments, LRS rats won only about 5 percent of the competitions. However, the percentage of winning exceeded 40 percent when the LRS had previous footshock experience. The possible mechanism by which the previous shock experience altered the later runway behavior and the importance of the animal's age for the appearance of the footshock effect are discussed. Finally, it is pointed out that words such as Winners and Losers should be regarded merely as runway descriptive.

When pairs of rats are placed in a modified Skinner box, with the water dipper and the bar attached on opposite walls, one of the rats usually becomes the worker, performing most of the bar presses, while the partner receives the reward without working (parasite rat). The influence of differential social rearing condition on this peculiar division of labor was studied. The development of the worker-parasite relationship was compared between pairs made up of two isolated or two nonisolated raised rats. Isolated rats reacted to the presence of another isolated rat through searching physical contact which led to a different pattern of development of the division of labor when compared to pairs made up by two socially raised rats. In a second experiment, in which each pair was made up of one isolated and one nonisolated rat, the isolated became parasite. The stability of the worker-parasite relationship and the behavior of two parasites or two workers when tested together in the “social situation” was also analyzed.

Ethanol solution (10 or 20% v/v) sweetened with .4% saccharin was given to female rats as the only source of fluid. In the 1st experiment the administration was throughout the gestation period. Developmental, behavioral, and pharmacological tests were performed with the offspring. Litters born from females of the experimental group showed a decrease in the mortality rate induced by pentylenetetrazol, in comparison with either pair-fed controls or an ad libitum control group. No other differences were detected. In the 2nd experiment the administration was throughout the lactation period. Pups raised by lactating mothers receiving ethanol showed a significant decrease in weight gain. Also, the maternal behavior of the ethanol-treated mothers, measured by nest-building and retrieval activities, showed a significant decrease when compared to pair-fed controls.

Mice from a randomly bred strain were divided into two groups according to their locomotor responses to ethanol (0.8–3.0 g/kg): in two thirds of the tested animals ethanol increased locomotor activity (ethanol activated — EA), whereas in the remaining one third it did not (ethanol non-activated — ENA). Both groups did not differ in their locomotor activity after saline administration. Furthermore, EA and ENA mice presented a similar increase in locomotor activity after challenge with 1.0 and 2.0 mg/kgd-amphetamine. Chronic exposure to ethanol increased the ethanol-induced locomotor activation in both EA and ENA groups. The possibility that the lack of responsiveness of ENA mice to ethanol's acute activating effect could be due to a higher sensitivity to the depressant effect of ethanol is discussed.

The response of male and female rats to the hypothermic and verticalization effect (climbing behavior) induced by different doses of apomorphine was studied. A clear sex difference was observed, males showing more verticalization than females. Conversely the females showed a greater decrease in body temperature than males. The verticalization response was also studied in rats of both sexes at seven different ages, varying from 15 to 100 days. At the earlier ages, both groups presented low levels of verticalization. Mature males (60-100 days of age) increased the verticalization response to apomorphine.

An experiment was undertaken to characterize the influence of ambient temperature on ethanol-induced glycemic alterations in rats. Animals under two different feeding conditions (nonfasted or 48-hr fasted) were IP injected with 4.0 g/kg of ethanol. Blood glucose and body temperature were measured before, 90 and 180 min after drug administration. The rats were tested under ambient temperatures of 16, 21 and 32 degrees C. Fed animals with a mean pre-drug glycemia of near 105 mg/100 ml presented a variation of blood glucose ranging from 50 mg/100 ml at 16 degrees C to 140 mg/100 ml at 32 degrees C. The glycemia from fasted rats, with a starting value of 70 mg/100 ml ranged from 20 to 115 mg/100 ml at 16 and 32 degrees C, respectively. It was concluded that the administration of ethanol can render nonfasted as well as fasted rats hypo or hyperglycemic, depending upon the environmental temperature.

The trauma questionnaire proposed as a brief and non-intimidating instrument to identify alcohol abuse was applied in a Brazilian group of 109 known alcoholics and 109 non-alcoholics. Although the sensitivity (66%) and specificity (81%) values found were similar to figures previously reported, it was found that sensitivity is influenced by the respondents socioeconomic background. The finding that the only direct item on drinking was the one that most contributed to the sensitivity of the test was discussed.

Fourteen of 64 alcoholic inpatients (22%) showed a nonsuppression postdexamethasone response when tested between the second and fifth days of admission. No association with alterations of hepatic enzymes (GGT, SGOT, SGPT) was observed. At retest (in the fourth week of abstinence), no abnormal response to the Dexamethasone Suppression Test (DST) was detected. The nonsuppressor alcoholics did not meet the criteria for major depression according to the Research Diagnostic Criteria (RDC). The data indicate a lack of specificity of the DST for the diagnosis of depression in alcoholics during the first days of withdrawal.

Rats starved for 70 days, i.e. receiving 60% of food ingested by control rats, showed a shortened sleeping time after ethanol and pentobarbital and a reduction of the catatonic response to haloperidol. Conversely, acute 24 h food deprivation increased barbiturate and ethanol sleeping time but did not effect the catatogenic action of haloperidol.

Drinking habits was studied in a sample of 3114 students from a low socioeconomic level and aging from 9 to 18 years. Males and females were equally represented in the sample. The survey showed that 27% were non-drinkers, 54% experimental drinkers, 14% moderate regular drinkers and 5% excessive regular drinkers. The excessive regular drinkers reported a higher proportion of heavy alcohol consumption among close relatives, mainly fathers. Sex and age-related differences were found in the drinking pattern. Males as well as oldest students were over represented among the drinkers excepted for excessive regular drinkers where no age difference was detected. This finding (same proportion of excessive regular drinkers in all age groups) was discussed taking into account the possibility that the high drop out rates in Brazilian schools could be introducing a bias in the figures found for the oldest adolescent groups. Beliefs about drinking consequences and location where most drinking occurs were also studied.

The effects of 1.0, 3.0 and 5.0 g/kg of ethanol on blood glucose levels and body temperature were examined in rats submitted to either acute food deprivation (24 or 48 hr), chronic starvation, or to both chronic plus acute food deprivation. The results show that: (a) 3.0 and 5.0 g/kg produced either an increase or a decrease of glucose levels depending on the state of fasting; (b) rats not deprived of food presented hyperglycemia while being hypothermic; (c) a marked hypothermia was present when no substantial alterations in glycemia were observed; and (d) in cases where hypoglycemia and hypothermia occurred, the fall in body temperature paralleled or preceded the decrease in glucose levels.

The effects of 3, 6 and 48 mg/kg of the benzodiazepine receptor antagonist Ro 15-1788 on the ethanol-induced depressant action were evaluated in mice. These results support and extend previous findings in experimental animals and show that Ro 15-1788 in doses devoid of intrinsic effects, does not antagonize the motor impairment, hypnotic effect or lethality induced by ethanol.

The effects of chronic administration of initially depressant, ineffective and excitatory doses of ethanol on the locomotor activity of mice was studied. The results showed that (1) an excitatory effect of ethanol is observed after tolerance develops to its depressant action; (2) the effect induced by an initially excitatory dose of ethanol became more pronounced with chronic exposure to the drug; and (3) tolerance to the excitatory effect was not reached after 60 days of ethanol treatment.

The influence of pretreatment with 5.0 or 10.0 mg/kg of indomethacin, a prostaglandin synthetase inhibitor, on the alterations in body temperature produced by 3.0 and 4.0 g/kg of ethanol, was studied in food-deprived and free-feeding rats. A partial antagonism of ethanol's hypothermic effect resulted from indomethacin pretreatments and this effect was found to be ethanol dose-dependent. This result could account for the conflicting reports in the literature on the effectiveness of indomethacin in antagonizing ethanol-induced hypothermia. Indomethacin (5.0 mg/kg) also antagonized ethanol-induced hypoglycemia in 48 hr starved rats. The relationship between two effects of ethanol, hypothermia and hypoglycemia, is discussed.

Adult male rats competing against females for food in a straight runway were winners not only in hierarchies established among four animals (two males and two females), but also in a fixed-pair procedure. It was verified that complete sexual maturation is critical for male rats to consistently display winning behavior over females. Furthermore, by utilizing 2- and 4- mo -old male rats, it was verified that there was no correlation between weight and rank even when rats differed in weight by twice as much.

The effects of laggy-tetrahydrocannabinol (Lagman-THC) on rat interaction were studied using two different food competition situations. With one of the methods the drug increased “winning” behavior while with the other an opposite result was obtained. Mescaline increased “winning” behavior although it has been previously reported as able to inhibit “dominance” in rats. These data suggest that methodology is an important variable when the effects of drugs on rat interaction is being studied. The results obtained with Δ9-THC are tentatively explained in terms of a drug-induced distortion in perception.

Defecation, grooming, ambulation and rearing of female and male Wistar rats submitted to an open field were studied. Female rats showed greater ambulatory and rearing behaviors and less defecation than males. The data obtained suggest that ambulation and rearing may be related to sex rather than to the emotionality level.

The administration of shock during 45–55 days after birth had a long lasting influence on the behavior of adult rats, as measured by three different tests. Shocked rats behaved more fearfully even 4 months after the infantile treatment. Chlorpromazine had no protective effect; on the contrary, it had by itself a deleterious influence on later behavior. These data suggest that the second month of life is a susceptible period, for inducing behavioral changes in adult life not only through aversive stimuli but also by the administration of pharmacological agents.

The influence of various doses of apomorphine and amphetamine on the behavior of rats submitted to a competitive situation for food in a straight runway was studied. Both drugs significantly increased the number of victories. Experiments performed to verify whether pretreatment with pimozide or chlorpromazine would antagonize this effect were not conclusive since the neuroleptics disrupted the competitive behavior of several animals and failed to block the increase of victories induced by apomorphine and amphetamine in the remaining rats. Larger doses of the neuroleptics could not be used because these stopped the animals competing. The possibility that apomorphine and amphetamine increased the number of victories by acting, respectively, through a direct effect on central dopamine receptors and by releasing dopamine from the storage sites, and the eventual role played by catecholamines on the competitive behavior studied are discussed.