ONTOGENY OF IMMUNOREACTIVE STEROIDOGENIC PROTEINS (ADRENODOXIN AND CYTOCHROME P-450(21)) IN THE INTERRENALS OF THE TELEOST LATES-CALCARIFER

Antisera against bovine adrenodoxin and cytochrome P-450(21) (steroid 21-hydroxylase) cross-reacted with the interrenal cells of the adult A sian seabass (Lates calcarifer); the cells were arranged as cords, two cells thick, in the headkidney. During larval development, cells immu noreactive for adrenodoxin were first observed 1 day posthatching (dph ); immunoreactivity for cytochrome P-450(21) was first detected at 1.5 dph. Initially, the interrenal cells occurred as a mass in each headk idney, which only became identifiable histologically at 5 dph. The num ber of interrenal cells increased with age, becoming associated with t he cardinal veins at 14 dph. The present study thus indicates that the posthatching rise in cortisol may originate from the nascent interren al tissue. (C) 1996 Academic Press, Inc.