Mitochondrial P-450 activities in aldosteronoma tissues.

Adrenal P-450 activities were measured by an in vitro reconstitution system from tissues obtained from human aldosteronomata, and the results compared with those of the normal adrenal tissues from patients with Grawitz's tumor. The P-45011 beta activity was significantly increased in adenoma tissue (55.6 +/- 5.3 vs 9.0 +/- 6.2 nmol corticosterone/mg of protein/min in the control tissues, P less than 0.01). P-450scc activity in adrenal adenomata was 13.4 +/- 2.0 nmol pregnenolone/mg of protein/min, significantly higher than control (P less than 0.05). The present results suggest that increased mitochondrial P-450(11 beta) activities may be characteristic of aldosterone-producing adenomata.