Depletion and replacement of the adrenaline and noradrenaline contents of the rat adrenal gland, following treatment with reserpine.

The effect of reserpine on the adrenaline and noradrenaline contents of rat adrenal glands has been studied. Given subcutaneously to male albino Wistar rats in 3 daily doses of 1 mg/kg, it caused, 24 hr after the final dose, a similar percentage loss of adrenaline and noradrenaline of approximately 50%. Subsequently the adrenaline content slowly increased, until at 14 days from the begining of the experiment there was no significant difference between the reserpine-treated and the control glands. In contrast, the recovery of the noradrenaline content was rapid, exceeding the control value at 7 days by approximately 250%. This increased content of noradrenaline declined to the normal level by 21 days. The total amine content returned to normal by 7 days and remained at this level subsequently. The effect of re-depleting the glands of their amine content was investigated. It was found that re-depletion at 7 days caused a preferential release of noradrenaline, followed at 14 days by a peak of noradrenaline at least as high as that obtained following the initial depletion only. Re-depletion at 21 days caused an effect similar to that obtained initially. Denervation of the left adrenal gland did not alter the degree of depletion caused by reserpine, nor did it alter the subsequent replacement of the amines as compared with that in the innervated right gland.