Comparative studies on some histocytochemical aspects of the caudal neurosecretory system of two freshwater teleosts, Clupeisoma garua (Ham.) and Ambasis ranga (Ham.).

Histocytochemical aspects of the caudal neurosecretory system of Clupeisoma garua and Ambasis ranga have been described with the help of certain histocytochemical techniques. Dalhgren cells perikarya show positive reactions for RNA and Nissl substances. These cells produce a proteinaceous secretion which contains NH2-group and aromatic amino acids. Lipid and phospholipid may be associated with the secretion. Predominant proteinaceous secretion lacks carbohydrates having 1: 2 oxidable glycol group, glycogen, acid mucopolysaccharides, and amino acids having--SS/--SH groups.