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The behavior of a number of motile flagellated bacteria toward viscosity characteristics of their fluid environments was observed. All showed an increase in velocity (micrometers per second) in more viscous solutions. Velocity reached a maximum at a characteristic value, however, and thereafter decreased with higher viscosities. Peritrichously flagellated bacteria had maximum velocities at higher viscosities than polarly flagellated bacteria. Effects of temperature, and possible utilization of chemical constituents in the viscous solutions, were studied and found to be negligible factors under the experimental conditions used. Different agents produced the same phenomenon, thus indicating that there probably were no chemically induced metabolic effects. Loss of available water and the possibility of a variable energy supply to the flagellar propulsive system were considered but are believed minimal. Theoretically derived thermodynamic equations were utilized and suggest that the conformation of the flagellar helix affects efficiency of propulsion. Such a relationship between helix waveform and velocity was experimentally observed with Thiospirillum jenese .

PIP: This is a general coverage of the entire topic of PGs (prostaglandins). It includes an extensive literature review. The history, nomenclature, biosynthesis, analytical methods of detection, stability, metabolism, pharmacodynamic effects, and clinical uses of PGs are discussed. The discussion of PG biosynthesis is illustrated with chemical structure diagrams showing the progression from prostanoic acid, the parent 20-carbon acid, to various PG analogs. Since natural PGs under both basic and acidic conditions are generally unstable, chemists encounter problems in synthesizing them and physical pharmacists in developing chemically stable dosage forms. The main clinical use for PGs is to induce abortions and labor. PGs also have powerful gastrointestinal, bronchoconstrictive, and antihypertensive properties.

Pentazocine, like amobarbital, enhances at low concentrations, but depresses at higher concentrations the QO2 of brain cortical slices from normal rats; under this condition morphine was in

Available published material of adverse reactions to prostaglandins (PGs) at various dosages routes and levels is reviewed. Animal studies are of 2 kinds: studies of pharmacological effects and studies of toxicological reactions (i.e., acute dose levels). The pharmacology of PGs show the drugs have 3 areas of action: 1) smooth muscle effects, either contraction or relaxation (cardiovascular effects and reproductive tract; relaxation of vascular smooth muscles by some PGs and contraction by others); 2) nervous system effects; and 3) lipid and carbohydrate metabolism. In humans, PGE1 was administered intravenously and it was found that adverse effects were related to rate of administration rather than to total dose; side effects included flushing, headache, visual disturbances, and restlessness, factors which might suggest a correlation with central nervous system effects (as found in animal studies). PGE1 administered at acute doses orally, by inhalation, and intradermally show effects attributable to gastrointestinal disturbances, respiratory problems, and erythematous responses. In general, studies in humans of other PGs have found similar adverse reactions, all of which are explained by known mechanisms of action of PGs. Dose levels constituting acutity are dependent on route (i.e., oral doses are much higher than intravenous doses), with rapid intravenous infusion causing the most adverse reactions.

In canine subcutaneous adipose tissue theophylline (2×10--4 M), cAMP and ATP (10--5 M), and DBcAMP (8×10--4 M) increased blood flow by by approximately 100 per cent. These compounds also antagonized sympathetic vasoconstriction. Theophylline and DBcAMP increased glycerol release dose-dependently, while cAMP and ATP were ineffective up to I mM. Theophylline (0.4–0.8 mM) potentiated the lipolytic effect of nerve stimulation, while 2–8 mM apparently caused maximal stimulation Per se. DBcAMP did not affect FFA release following nerve stimulation, while DBcGMP potentiated. The apparent rate of re-esterification, glucose uptake and lactate release was decreased by theophylline. DBcAMP (0.1–0.4 mM) had no effect on these parameters, while DBcGMP at the same concentration decreased re-esterification and lactate release. Stimulated overflow of 3H from tissues prelabelled with L-3H-noradrenaline was reduced to 50 per cent by ATP (0.1–0.4 mM), but was unaffected by DBcAMP and DBcGMP at the same concentration. The results support the view that cAMP mediates the metabolic actions of sympathetic nerve stimulation in canine subcutaneous adipose tissue. The relationship between cAMP and vascular reactions may be more complex.

Locomotion in the Pulmonata may have two, distinct, negative effects on total metabolism. Energy losses may occur via mucus secretions and also as a result of muscular and ciliary activities. These aspects of pulmonate metabolism were investigated in two freshwater species; Ancylus fluviatilis and Planorbis contortus. The former is a herbivore which feeds on periphyton and the latter is a detrivore which appears able to make use of bacteria.Speed of movement was influenced by starvation time, food availability, and water movement, although the extent to which these factors affected locomotion showed some variation with species. In still conditions P. contortus moved more rapidly than A. fluviatilis whereas the converse occurred under conditions of more violent water movement. During deprivation, however, both species showed similar responses in that their rate of locomotion increased to some maximum and then fell, and their pattern of movement became more random. These strategies were explained in terms of fitness.Under conditions of satiation locomotion had a measurable quantitative effect on P. contortus only, and contributed ca. 20% to routine metabolism. Nevertheless, under conditions of starvation locomotion influenced the respiratory metabolism of both species and in this case there were clear differences between the respiratory rates of constrained and non-constrained subjects. These results were used to explain certain differences recorded by earlier workers on the relationship between starvation and respiration in freshwater snails.Energy losses via mucus secretions were found to make a significant contribution to snail energetics, representing between 13-32% of the energy absorbed across the gut wall. However, the potential energy thus released may not be completely lost from the secreting system because mucus was found to stimulate the growth of those bacteria which are preferentially ingested by P. contortus. Consequently, mucus may play a provendering role and should not be ignored as a vehicle of biologically useful energy in aquatic or terrestrial ecosystems.

Summary Combined treatment of hyperlipidaemia with the nicotinic acid derivative pentaerythritol tetranicotinate (Perycit ® ) and clofibrate or the clofibrate analogue cholesolvin has been used in 26 ambulant patients with different types of hyperlipidaemia (types IIa, IIb and IV). The treatment started with Perycit ® 1g × 3 daily followed by cholesolvin 1 g × 2 or vice versa. The two drugs were then given together in the same doses as before and finally clofibrate was substituted for cholesolvin. The two types of drugs, Perycit ® and cholesolvin or clofibrate respectively, were found to have additive synergistic effects on plasma cholesterol as well as on plasma triglyceride concentration. There was no difference between cholesolvin and clofibrate in this respect. The usual side effects like flush were seen with Perycit ® , but the combined treatment with Perycit ® and cholesolvin or clofibrate produced no additional adverse reactions.

“Activated” macrophages, isolated from lungs of BCG-infected rabbits, exhibited a greater perturbability of oxidative metabolism than their normal counterpart, when exposed in vitro to unrelated microorganisms or treated with phospholipase C. They were much less metabolically responsive when incubated with Concanavalin A. The metabolic effect of this lectin gradually decayed as time elapsed from the day of infection. These results are interpreted to show a modification of the surface properties of the macrophage in the course of the immunological activation. The possible mechanisms of generation of these surface alterations are discussed.

The results of a metabolic test with short-term administration of small doses of human growth hormone (2 mg/m2 of HGH Raben daily) in 17 hypopituitary dwarfs and in 15 control children are described. A much greater N-retention is found in the hypopituitary patients. The excretion of creatinine and creatine decreases and the excretion of calcium increases in both groups. Serum urea-N decreases in both groups. Serum α-NH2-N increases and the α-NH2-N-clearance decreases in the hypopituitary patients, while this is not the case in the control children. Serum inorganic phosphorus increases and alkaline phosphatase decreases in the hypopituitary patients. An attempt has been made to correlate some of the metabolic responses.

Acute hypothermia (15 °C rectal temperature) has been induced in fasted rats with and without prior intraperitoneal administration of urea. In the hypothermic animal, not given urea, blood glucose and pH were significantly decreased; blood lactic acid, inorganic phosphorus, and packed cell volume were significantly increased; no alterations occurred in blood levels of pyruvic acid, total acid-soluble phosphorus, urea, nor amino nitrogen. Prior administration of urea prevented significant alterations of blood glucose and lactic acid in the cooled animal. In the non-cooled animal, urea treatment resulted in elevated blood glucose levels. These effects are discussed in relation to the beneficial action of urea in permitting successful resuscitation and survival in a normal condition of rats cooled to rectal temperatures of 0–3 °C.

DIETARY measures in the treatment of hypertension have been advocated periodically during the past fifty years and have been extensively reviewed recently.1 The metabolic effects of the rice diet have been reported previously in abstract form.2 Although the most recent empirical program, as outlined by Kempner,3 is of limited value in the treatment of most patients with hypertensive vascular disease because of its rigid restrictions on diet, rather striking improvements in the level of blood pressure and general condition have been observed in some patients. The physiologic changes responsible for such improvement as may occur in these patients are, however, . . .

SummarySoterenol produced hyperglycemic and hyperlactic acidemic responses in the fasted rat nearly identical to those elicited by isoproterenol. The metabolic effects of both drugs were antagonized similarly by so-talol.

Human growth hormone was administered in doses of 5 mg daily to a female pituitary dwarf aged 14 years.Marked retention of nitrogen, potassium and phosphorus was demonstrated.There was also some re...

Phenylthiourea injected ip into Sprague-Dawley male rats elevates blood glucose and depletes liver glycogen. The susceptibility of rats to these effects varies directly with age as does the susceptibility to the pulmonary edema and to acute toxic effects. Cysteine and reduced glutathione protected against the pulmonary edema as well as prevented the hyperglycemia and partially diminished the liver glycogen depleting effect of a toxic dose of PTU. Methionine protected against the metabolic changes but did not prevent the pulmonary edema and acute toxicity. The hyperglycemic effect of PTU was not seen in the rats made tolerant to its toxic effects. Tolerant rats were severely depleted in their liver glycogen content. The metabolic disturbances in response to PTU seem to be secondary to its pulmonary effects.

SUMMARY Five monoamine oxidase inhibitors (MAOI) were tested for a correlation between MAO blocking potency, the effect on somatotrophic hormone (STH) production and metabolic effects on the pituitary. Mebanazine, N-acetyl-mebanazine and pargyline inhibited STH production, body weight gain and glucose-6-phosphate (G-6-P) dehydrogenase activity. MAOI which contain a hydrazine group (mebanazine and N-acetyl-mebanazine) also inhibited alkaline phosphatase activity as well as DNA and RNA formation in the pituitary, while pargyline, which contains an amino group, was inactive in these respects. Iproniazid and norpargyline were inactive with regard to STH production, body-weight gain and metabolic activities of the pituitary: alkaline phosphatase activity, G-6-P dehydrogenase activity, and DNA and RNA content. This suggests a relation between the ability of an MAOI to inhibit STH production and inhibition of the phosphogluconate oxidative pathway.

Numerous studies have been carried out in which the metabolic effects of exercise on teleosts have been noted (Fry, 1957; Heath and Pritchard, 1962; Brett, 1965; Brett and Sutherland, 1965; and Smit, 1965). Such studies have led to the conclusion that the "scope for activity" or "metabolic expansibility index" of fish permits an "active" oxygen consumption as great as eight times that of the resting or "routine" level. By mammalian standards this elevation in oxygen uptake is not phenomenal, but, considering the circulatory and respiratory limitations of fish, it would be interesting to know what adjustments in these systemic functions accompany exertion in fish. Directly opposed to an elevation in cardiac output is the series arrangement of resistant capillary networks of the gills and body, and in some species blood returning to the heart must pass through a third resistance found in the anastomoses of the kidney and liver.

Introduction The effects of corticosteroids on ocular tension have received considerable attention of late, since exogenous steroids have been reported to produce ocular tension increases. Certain topical glucocorticoids, after varying periods of time, have caused ocular tension rises in both glaucomatous and normal individuals. 1-3 Minimal ocular tension increases have also been noted in some patients after long-term usage of systemic glucocorticoids. 4 The tension elevations after both topical and systemic steroids were secondary to reduced facility of outflow. It is difficult to be certain of the metabolic basis for the ocular tension effects of these steroids. The uncertainty is due to the multiple metabolic effects (eg, anti-inflammatory, glycogenic, catabolic, osteoporotic, and electrolytic) of glucocorticoids. The only adrenal cortical hormones available with predominantly one mode of action (electrolytic) are the mineralocorticoids. Any ocular tension effects of these hormones might elucidate similar effects of other adrenal hormones. This study was undertaken

Extract Bunamidine is widely used as an anthelmintic in dogs in New Zealand but its use is restricted by occasional deaths which are difficult to explain. Unfortunately, most deaths occur in farm dogs and few autopsy examinations are possible. It seems that some dogs that die within a day of treatment show severe fatty change in the liver, and in some of these it was clear that the liver injury preceded the treatment. For this information the writers are indebted to the field observations of G. A. Thompson, National Hydatids Council (Fastier, 1972).

SUMMARY 1. The protein anabolic properties of three derivatives of testosterone have been investigated. 2. 17α-methyl-Δ5-androstene-3β: 17β-diol and 17α-methyl androstane-3α: 17β-diol produced nitrogen retention in doses approaching those reported as androgenic by other investigators. 3. The third compound, 17α-ethyl-19-nortestosterone (17-ENT), which was studied in greatest detail, produced nitrogen retention in moderate dosage. Other metabolic effects were a fall in urinary calcium and, usually, a fall in faecal calcium. Phosphorus balance agreed with that calculated from nitrogen and calcium balance. Plasma calcium showed no consistent variation, while plasma phosphorus fell. 17-ENT also brought about marked changes in weight, and in fluid, sodium, potassium and chloride balances which are probably due partly to the retention of nitrogen and corresponding intracellular fluid, and partly to increased sweating. When given to two patients with osteoporosis due to prolonged steroid therapy, and receiving prednisone, the compound appeared to aid the restoration of a positive calcium balance. 17-ENT was found to have definite androgenic effects, but their intensity requires further study.

The metabolic effects of human growth hormone may be segregated into two classes which can be termed “insulinlike” (or “anabolic”) and “contra-insulin” (or “diabetogenic”). It is proposed that the “anabolic” actions of HGH are optimized by the presence of insulin, whereas the “diabetogenic” actions are dominant in the absence of insulin. In line with this notion, the sequential release of insulin and of HGH which follows protein ingestion, or aminoacid infusion may serve to route aminoacid toward protein, while buffering changes in plasma glucose concentration.

Male albino rats were fed isocaloric diets (5%, 20%, and 40% protein and 10% corn oil by weight) in restricted amounts (6 g/rat per day) at environmental temperatures of 22 °C and 2 °C. Measurements were made of urinary excretion of nitrogen, potassium, sodium, phosphorus, and creatinine, of blood levels of glucose, urea, amino nitrogen, packed cell volume, and serum total proteins and of body contents of protein, moisture, and total crude fatty acids. Metabolic effects of food restriction were readily apparent at 22 °C and the diet appeared to play a role in modifying some of these effects in approximate proportion to the dietary protein level. With superimposition of cold exposure, metabolic differences among groups were decreased in degree with some suggestive evidence of a beneficial effect of increased dietary protein level and of a deleterious effect of decreased dietary protein (high carbohydrate) under these conditions.

The problem of ozone injury to plants is discussed in relation to natural sources of ambient ozone, susceptible plant species and the symptoms produced, environmental predisposition, metabolic effects, as well as how plants may be protected from damage. The degree of injury to susceptible plants is directly related to the concentration of ozone to which they are exposed and to the duration of the exposure. A list of plants that have been reported as susceptible to ozone injury is included.

The studies described in this report were initiated in an effort to elucidate the mechanism of action of the sulfonylurea compounds. It seemed to us that a broad clinical investigative approach, involving the study of a large number of conditions in which the metabolism of carbohydrate is disturbed, was most likely to eliminate quickly a number of possible modeg of action and to define more sharply the areas upon which further effort should be concentrated. Thus, extensive metabolic-balance studies and numerous individual testing procedures have been performed before, during, and following the administration of carbutamide (BZ-55) and/or tolbutamide (Orinasei) in the following subjects: (1) healthy young men; (2) three middle-aged, obese, stable diabetics; ( 3 ) an unstable diabetic of normal weight; (4) a patient with lipo-atrophic diabetes; ( 5 ) a totally depancreatized woman; (6) patients with coexisting diabetes mellitus and Addison’s disease, familial diabetes and Cushing’s syndrome, and diabetes and panhypopituitarism; and (7) an acromegalic with mild diabetes. Although the data reported below do not define a specific mode of action of the sulfonylurea compounds, they eliminate from consideration a number of important possibilities. Results

IT WAS demonstrated earlier that, provided carbohydrate in the form of glucose or starch is available in large amounts to hypophysectomized rats, hepatic lipogenesis, as judged by the conversion of acetate carbon to fatty acids, does not differ significantly from that observed in normal rats (1). Our findings offered no support for the view that hepatic lipogenesis is accelerated in the absence of pituitary hormones (2, 3, 4). Indeed, when hypophysectomized rats were fed a stock diet adequate in all respects, but containing whole ground wheat as the major carbohydrate source, lipogenesis and cholesterogenesis in their livers were below normal (1). The results obtained by Hill et al. (1) emphasize the need for a careful evaluation of the nutritional state of the hypophysectomized animal before ascribing a metabolic effect to the removal of the anterior pituitary gland. It is now generally agreed that the diabetic animal has lost, to a considerable extent, its capacity to form fat from carbohydrate (5, 6).

Vascular and metabolic effects of intravenous (i.v.) infusion of noradrenaline and isoproterenol were examined in the inguinal fat pad of dogs before and after inhibition of lipolysis by nicotinic acid. These catecholamines raised fatty tissue blood flow (FBF) similarly before and after such inhibition, while fatty tissue oxygen consumption (F-VO2) rose significantly less after administration of nicotinic acid. It is concluded that increased FBF by catecholamines is not due to enhanced lipolysis, whereas the calorigenic effect is partly caused by their lipolytic action.

ConclusionsThe iodine content in thyroid preparations seems to be an approximate guide for the estimation of metabolic effect; however relatively large deviations do occur in some products. The effect on the heart is not related to the metabolic action. The thyroxine content has still less demonstrable proportionality to either physiologic effect. While hydrolysis of thyroid globulin increases its heart action hydrolysate from muscle tissue is inert in that respect.