EFFECTS OF DRUGS ON BEHAVIOR HEART RATE AND CATECHOLAMINE LEVELS IN THIAMINE-DEFICIENT RATS

To discover the cause of the increased catecholamine levels seen in thiamine-deficiency, the relationships between the changes in tissue catecholamine level, behavior and heart rate after administration of tyramine, reserpine and amphetamine were investigated. After the injection of reserpine the catecholamine content slowly decreased in thiamine-deficient rats for 5 hours and during this time neither sedation nor change in the heart rate were observed. Amphetamine caused a greater decrease in tissue catecholamine content and more excitement in the deficient group than in the control group. The release of catecholamines caused by tyramine was similar to that caused by amphetamine; in the deficient group the release was accompanied by a marked increase in heart rate, but no behavioral changes were caused by tyramine injection in any group. The nature of the accumulated catecholamines in thiamine-deficiency is discussed with special reference to their storage and release. © 1969.