Effect of the Subcommissural Organ and the Pineal Body on the Adrenal Cortex

The authors studied the effect of extracts of the subcommissural organ (SCO) and of the pineal body on the zona glomerulosa and zona fasciculata of the adrenal cortex in rats. The SCO extract induced an acute activation of the cells of the zona glomerulosa, shown by a 34–39% increase in the volume of nuclei. This effect is observable within one hour after the administration of the organ extract and is present for 4 hours. The pineal body extract caused a minor functional increase of the zona glomerulosa in some cases. In the zona fasciculata, the pineal body extract caused only a slight functional increase, and the effects of the SCO also were only slightly significant. The authors presume that the SCO produces a substance by which, directly or indirectly, the function of the zona glomerulosa of the adrenal cortex (aldosterone secretion) is increased.