Histochemical and spectrophotometric demonstration of hydroxysteroid dehydrogenase activity in the presumed steroid producing cells of the brook lamprey (Lampetra planeri Bloch) during metamorphosis.

Pronephric, opisthonephric, ovarian, and testicular tissue rich in presumed steroid producing cells taken from the brook lamprey during metamorphosis was investigated by histochemical and spectrophotometric methods. Histochemical results seemed to provide evidence for hydroxysteroid dehydrogenase activity using pregnenolone as substrate. Spectrophotometric evidence for hydroxysteroid dehydrogenase activity was obtained from presumed adrenocortical tissue, ovarian and testicular homogenates using pregnenolone, dehydroepiandrosterone, androsterone, and 3 beta, 17 beta-dihydroxy-5 alpha-androstane as substrates.