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M Hydinger

Publications and source records attributed to M Hydinger.

4 recordsLinked to original sources

Comparison of thyrotropin-releasing hormone with melanocyte-stimulating-hormone-release-inhibiting factor as pentobarbital antagonists in monkeys.

Thyrotropin-releasing hormone (TRH), 0.1 mg/kg, i.m., significantly counteracted pentobarbital narcosis in six monkeys, but melanocyte-stimulating-hormone-release-inhibiting factor (MIF), 0.1 mg/kg i.m., did not. Earlier dose-response studies in unanesthetized monkeys had shown that this dose of MIF stimulated motor activity; this dose of TRH had shown no stimulant effect, but a higher dose depressed activity. Thus, an MIF dose that stimulates unanesthetized monkeys does not reverse pentobarbital narcosis; a TRH dose that by itself is neither stimulant nor depressant does partially reverse pentobarbital narcosis.

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MIF, TRH, and simian social and motor behavior.

MSH-release-inhibiting factor (MIF) and thyrotropin-releasing hormone (TRH) both have been reported to modify mood and activity in man. These two hypothalamic peptides were given intramuscularly across a 1000-fold dose range to 5 juvenile male M. nemestrina monkeys living in a social group. Motor activity was recorded automatically, and an observer counted various social behaviors. MIF increased motor activity for up to 11 hr. It decreased quiet foraging behavior, but did not change behaviors of social interaction. TRH did not stimulate motor behavior; high doses strongly suppressed it and produced apparent somatic distress. TRH increased behaviors of quiet rest and association and decreased environment exploration and low-intensity dominance behaviors. The lowest dose of TRH increased social play. Two monkeys showed repetitive, stereotyped behaviors even in baseline observations, and certain doses of TRH and MIF may have increased the frequency of these behaviors.

Animals↗

Monkey motor stimulation and altered social behavior during chronic methadone administration.

To assess the effects of chronic methadone administration on locomotor, social, and eating behavior od drug-native individuals under circumstances approximating those of methadone "maintenance" clinics, we gave single, daily oral doses of methadone to 5 Macaca radiata monkeys living in a social group. We obtained motor activity counts automatically during 6 weeks of baseline, 10 weeks of drug administration, and 3 weeks of post-drug abstinence. Social behaviors of association, dominance, submission, and sexuality were counted 5 days per week, and animal weights, food eaten and food-reinforced work were recorded. Plasma methadone levels were near those achieved in mechadone clincs. Methadone produced mixed stimulation and sedation in the daytime, with stimulation predominating for 4 hrs following administration. At night the subjects moved less while taking the drug. Associative behaviors were reduced by methadone, but dominance, submission, and sexual behaviors were not altered. The monkeys ate less while taking the drug, losing weight and working less for food. In these primates methadone had significant stimulant properties, impaired important social behaviors, and reduced the potency of food as a reinforcer of work. The results are compared with methadone's effects upon humans.

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