Steroid production by incubated mouse adrenals: II. Control of steroid output

ACTH is far more effective in increasing the steroid output of the mouse adrenal than the rat adrenal in vitro. It mainly affects the production of corticosterone, but that of the two polar fractions is also increased. The response by mouse adrenals to ACTH decreases with incubation time, but the output of corticosterone is less affected than that of the two polar fractions. The unstimulated output of total lipid remains constant over a period as long as ten hours. The dose-response to ACTH, over two hours, is linear between 0.1 and 1 unit per 100 mg, and logarithmic at all higher concentrations that could be kept in solution. The adrenal of the mouse and rat does not appear to distinguish between concentration of ACTH, only between amounts. The response to ACTH is not affected by sectioning the glands; it is greatly increased by calcium.