PT - JOURNAL ARTICLE AU - D. I. MACHT AU - C. F. MORA TI - EFFECT OF OPIUM ALKALOIDS ON THE BEHAVIOR OF RATS IN THE CIRCULAR MAZE DP - 1920 Oct 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 219--235 VI - 16 IP - 3 4099 - http://jpet.aspetjournals.org/content/16/3/219.short 4100 - http://jpet.aspetjournals.org/content/16/3/219.full SO - J Pharmacol Exp Ther1920 Oct 01; 16 AB - 1. The behavior of albino rats before and after injections of opiates, was studied in the circular maze. 2. It was found that morphin produced a depressant effect on the behavior of the animal, after both large and small doses, but that in the case of one animal the drug exhibited a stimulating effect. 3. Of the other opium alkaloids, with the exception of papaverin, all were found to be slightly depressant. 4. Combinations of morphin with other opium alkaloids are, on the whole, somewhat less depressant than equivalent doses of morphin when given alone. 5. In all the experiments, even where large doses of the narcotics were administered, and marked and prolonged impairment of the psychological functions was produced, the animals eventually recovered their activity.