The effects of pineal indoles and a crude aqueous pineal extract on ACTH mediated corticosterone release by isolated adrenal cells.

An aqueous extract of bovine pineal tissue contained a principle which caused a potent inhibition of ACTH mediated corticosterone release by isolated adrenal cells, whereas a similar extract of cortical tissue did not have any effect on this process. Two pineal indoles were tested. Melatonin (10^?8 M) did not have any significant effect, whereas 5-methoxytryptophol (10^?8 M) caused a variable but significant additive effect on ACTH mediated corticosterone release. We are uncertain at the present time if this principle is similar to the reported pinealantigonadotropin.