Increased Toxicity of Serotonin in Adrenalectomized Animals

Abstract

ADRENALECTOMIZED rats and mice are more sensitive to anaphylactic shock^1,2, and to the action of histamine³ and 5-hydroxytryptamine^2,4 which may be involved in the anaphylactic reaction⁵, than are intact animals. The toxicity of histamine and of serotonin, as well as anaphylaxis, is increased by the administration of ‘pertussis vaccine’ and in old and tumour-bearing animals⁶. The present communication reports the toxicity of serotonin in rats and mice in some of these experimental conditions. Sprague–Dawley rats and ALAL mice (obtained from the firm ALAL, Milan), of an average weight shown in Table 1, were injected by different routes with 5 - hydroxytryptamine – creatinine - sulphate (kindly supplied by Vister Labs, Casatenovo, Como). Adrenalectomy was performed 72 hr. before injection ; partial hepatectomy—according to the method of Higgins and Anderson⁷—was carried out 48 hr. before, and Walker carcinosarcoma was implanted 15 days before.