Inhibition of compensatory ovarian hypertrophy in the mouse and vole: a comparison of Altschule's pineal extract, pineal indoles, vasopressin, and oxytocin

The antigonadotropic action of an aqueous pineal extract, purified pineal indoles, vasopressin and oxytocin were compared using the mouse compensatory ovarian hypertrophy model. Four indoles, N-acetylserotonin, melatonin, 5-hydroxytryptophol, and 5-methoxytryptophol in 100 μg doses given as a single intraperitoneal injection on the day of surgery were found to be effective in inhibiting compensatory ovarian hypertrophy (COH) measured 9 days later. 5-Hydroxtryptophan, serotonin, 6-hydroxymelatonin, 5-hydroxyindoleacetic acid, and 5-methoxyindole acetic acid were ineffective in the same doses. Vasopressin (2.2 μg) and the aqueous pineal extract significantly depressed COH while oxytocin (2 μg) was ineffective. Preliminary studies in the vole (Microtus moutanus) demonstrated that COH occurred and was significantly blocked by melatonin and Altschule's aqueous pineal extract, demonstrating the anti-FSH action by pineal principles in induced ovulators similar to that described above in spontaneous ovulators (mice).