Portland State University. Department of Psychology
Date of Award
Master of Science (M.S.) in Psychology
1 online resource (52 pages)
Marijuana -- Research, Marijuana -- Physiological effect, Tetrahydrocannabinol, Rats -- Behavior -- Effect of marijuana on
Since hunger drive is often used as a motivating factor in animal learning experimentation, it was decided to determine the effects of marihuana extract distillate on the eating behavior of rats. Carlini and Kramer (1965) found marihuana extract injections to have a faciliatory effect upon maze performance. They suggested that facilitation could have resulted from and increase in hunger drive. However, if the dosage level is high, this effect may last for a short time and be followed by a disinterest in food. Scheckel et al. (1968) report that some monkeys, at very high dosage levels of tetrahydrocannabinol starved to death in post-drug depressions. Human studies indicate some increased hunger or "taste enhancement" (Grinspoon, 1968; Hollister, et al., 1968; Ames, 1958).
Ss were 20 male and 20 female adult Sprague-Dawley albino rats, maintained in home cages with ad-lib food and water. Each animal was assigned to one of five groups so that each group contained four males and four females. Each group received one dosage level of the drug throughout the entire experiment. Three dosage levels and two controls were used. Food deprivation levels of ad-lib, 12, 24, and 48 hours were assigned according to a balanced Latin square design. The drug, marihuana extract distillate, was administered through an intraesophogeal tube and hypodermic syringe. The study was divided into two parts, each of four weeks' duration. In the first, after administration of the frug, the animals immediately were placed into a cage with a known amount of food present. The food was weighed after three and 24 hours to determine the amount of food eaten. The second experiment in the study repeats all proc3edures except animals were not given food until 1/2-hour after the drug was administered.
Results show an inverse relationship between dosage level of marihuana extract distillate and amount of food eaten. Effects of dosage level, hours of deprivation, sex, latency of food preparation, and the possibility of tolerance or increased sensitivity to the drug are discussed.
Wetle, Terrie, "The Effects of Marihuana Extract Distillate on Eating Behavior of Rats" (1971). Dissertations and Theses. Paper 1520.