Functional morphology of the interrenal and chromaffin cells in the teleosts, Rasbora daniconius (Hamilton), Barbus stigma (Cuv. et Val.) and Channa gachua (Hamilton).

The interrenal cells in Rasbora daniconius, Barbus stigma and Channa gachua are mainly found around the postcardinal vein and its major branches in the haemopoietic head-kidney. The chromaffin cells which are identified by the positive chromaffin reaction are found in the walls of the postcardinal vein or dispersed among the interrenal cells. delta5-3beta-HSDH and G-6-PDH activity was observed in the interrenal cells of all three teleosts. The present work indicates that the interrenal cells are capable of steroid biosynthesis and the chromaffin cells contain biologically active catecholamines.