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This study was performed to investigate ethanol self-administration in inbred Maudsley rats, which were selected for differences in stress susceptibility and which often differ in their home cage ethanol consumption. Adult, male, Maudsley reactive (MR/Har) and Maudsley nonreactive (MNRA/Har) rats were tested in a standard protocol for the sucrose-substitution procedure for the initiation of self-administration of ethanol in an operant setting. Before and after initiation for self-administration in the operant setting, rats were tested for home cage consumption of 10% (vol./vol.) ethanol in a two-bottle test for 14 consecutive days. During the sucrose-substitution procedure, MNRA/Har rats consumed more sucrose and ethanol than did MR/Har rats. In addition, MNRA/Har rats self-administered a greater amount of ethanol during a concentration manipulation with the use of a fixed ratio (FR) 4 response requirement. However, both strains self-administered low amounts of 10% ethanol (MNRA/Har, 0.15 g/kg/day; MR/Har, 0.08 g/kg/day) after concentration manipulation compared with those observed in outbred rats and alcohol-preferring rats tested under identical conditions in other studies. Both MR/Har and MNRA/Har rats markedly increased their ethanol intake in the home cage after the initiation protocol, but there was no difference between MR/Har and MNRA/Har on that measure. The failure of MR/Har rats to self-administer ethanol was inconsistent with their home cage drinking in other studies, and this is distinctly different from the self-administration pattern of high-alcohol-drinking rat lines tested in this paradigm.

Male Maudsley reactive (MR/Har) rats often exhibit marked ethanol or alcohol preference (AP) after forced (one-bottle) exposure to 10% [volume/volume (vol./vol.)] ethanol, but exhibit variable AP without this exposure. In this study, we examined manipulations of one-bottle exposure to ethanol (10% ethanol as the sole source of fluid) in three experiments. In Experiment 1, we recorded voluntary consumption of 10% ethanol during 5 weeks of two-bottle choice in male and female MR/Har rats after 0, 1, 2, 3, or 4 days of one-bottle ethanol exposure. The results showed that, in male rats, one day of one-bottle exposure was as effective as multiple days in increasing AP relative to findings for ethanol-naive (control) rats. Female rats were not affected by one-bottle exposure. They drank equal amounts of ethanol across all groups and in greater amounts than observed for male rats (relative to body weight). The results of Experiment 2 supported the suggestion that 18 h of exposure to ethanol was similar to 24 h of exposure for increasing subsequent ethanol consumption, and that 12 h of exposure increased AP relative to findings for ethanol-naive rats, but on a delayed basis and at a lower level than that observed for 24 h of exposure. In Experiment 3, we tested whether these increases in ethanol consumption, observed in male MR/Har rats after one-bottle exposure to ethanol, might be related to habituating to an unpalatable substance. Thus, rats had one-bottle tests with either a 10% ethanol solution (as in earlier studies) or a 0.01 mmol quinine solution, after which groups of rats were tested for voluntary consumption (two-bottle test) of one of these solutions and water. Results showed that although rats in the quinine-exposed group drank more fluid than that consumed by rats in the ethanol-exposed group during the one-bottle period, rats preferred ethanol to water and avoided quinine relative to water during the 5 weeks of two-bottle choice. The results seem to indicate that relatively small amounts of 10% ethanol can markedly increase subsequent AP in male MR/Har rats, and that this increase in AP does not seem to be attributable to a process of habituating to an unpalatable fluid.

"Like Gulliver in Lilliput, the United States risks being tied down by a thousand threads Walter Mead thus concisely summarizes, I think, the challenges facing the United States in adopting a national security strategy adequate to the task of taking it into the next century It is in those "thousand threads" that I find the basic flaw of President Clinton's policy of engagement, and why I will argue that the idea of pivotal states, as proposed by Chase, Hill, and Kennedy,2 is the preferred organizing concept for U S national security strategy.

Summary In boars and rabbits, administration of adrenocorticotropic hormone (ACTH) results in a testis-dependent, short-term increase in concentrations of testosterone in peripheral plasma. This experiment was designed to assess the short-term effects of a single ACTH injection on plasma concentrations of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH) and cortisol in stallions. Eight light horse and two pony stallions were paired by age and weight and then one of each pair was randomly assigned to the treatment (ACTH, .2 IU/kg of body weight) or control (vehicle) group. Injection of ACTH increased (P .10) in concentrations of cortisol during the blood sampling period. Control stallions exhibited a midday increase (P>.05) in concentrations of testosterone similar to that reported previously; ACTH treatment prevented or delayed this increase such that concentrations of testosterone in treated stallions were lower (P