Reduction of pituitary nucleic acids, proteins, LH and FSH by melatonin-free pineal extract in rats stimulated with gonadotropin releasing hormone.

The effect of a pineal treatment on the pituitary gland under exogenous stimulation with gonadotropin releasing hormone (GnRH) was assessed in the rat. A pretreatment with melatonin-free pineal extract under the above conditions caused a statistically significant decrease in the pituitary concentrations of DNA--by 21%, RNA--by 28%, proteins--by 19%, LH--by 25% and FSH--by 22%. Authors' findings show that the melatonin-free pineal extract plays a role in the metabolism of nucleic acids and pituitary proteins besides being implied in the synthesis of gonadotropic hormones.