Effect of 5-hydroxytryptophan on muricide response induced by thiamine deficiency.

Male Wistar rats maintained on a thiamine deficient diet showed the mouse-killing response (muricide). On the 30th day of experimental feeding, the incidence of the muricide response was 78% in the thiamine deficient group. Intraperitoneal (i.p.) injection of 5-hydroxytryptophan (5-HTP) suppressed the muricide response in a dose-dependent manner. The suppressive effect of 5-HTP on the muricide response was potentiated by pretreatment with Ro4-4602. On the 20th day of experimental feeding, the incidence of the muricide response was 42.9% in the thiamine deficient group, 14.3% in the pair-fed group and 0% in the control group, respectively. The incidence increased to 92.5% in the thiamine deficient rats 24 hr after the i.p. injection of 100 mg/kg parachlorophenylalanine. The results of the present sutdy indicate that the injection of 5-HTP was effective in suppressing the muricide response induced by thiamine deficiency.