A PHARMACOLOGICALLY ACTIVE AGENT IN THE REPRODUCTIVE SYSTEM OF INSECTS

Abstract

The opaque accessory secretion from the male reproductive system of insects has been characterized in various ways. It exerts a melanophorotropic effect on the melanocytes in the skin of the frog, Rana pipiens, a property which, among naturally occurring compounds, is shared only by the indolalkylamines. The secretion also increases the rate of beating of the heart of the cockroach Periplaneta americana; its activity in this respect is unaffected by heating or by incubating with the enzyme trypsin, but it is destroyed by the action of the enzymes monoamine oxidase, tyrosinase, and o-diphenol oxidase. The active principle is associated with particles from which it is slowly released into solution. It is tentatively concluded that the material is an o-dihydroxyindolalkylamine.