Demonstration of a Human Atrial Natriuretic Peptide-Like Material in the Stable Fly, Stomoxys Calcitrans

Abstract

Atrial natriuretic peptide (ANP) is a peptide first reported in humans (hANP) and later in other mammals (Flynn, et al., 1987). More recently, similar peptides have been isolated from lower vertebrates (Miyata, et al., 1988; Sakata, et al., 1988). Although the precise mechanism of action of this peptide is not well understood, the gross effects when administered in these animals are vasodilation and increases in the rates of excretion of water and electrolytes, particularly sodium. The mammalian ANP’s are extremely well conserved 28 amino acid peptides with only one amino acid substitution at the 12th position. Due to my interest in stable fly diuresis, I decided to examine the possible existence of similar peptides in this insect. In this communication I shall report evidence for the presence of hANP-immunoreactivity in the stable fly.