Effects of Pituitary and Adrenal Hormones on the Numbers of Thoracic Duct Lymphocytes

The endocrine influences of hypophysectomy, adrenalectomy, and the administration of pituitary and adrenal hormones on the level of thoracic duct lymphocytes have been studied in test animals under standardized conditions. The following effects have been noted:

1. Numbers of thoracic duct lymphocytes are elevated after either hypophysectomy or adrenalectomy in the rat.

2. After the administration of either ACTH protein or pepsin peptide mixtures to normal or hypophysectomized rats, the number of thoracic duct lymphocytes is significantly reduced. This effect was not noted in adrenalectomized rats. These effects were observed two hours after administration of the ACTH preparations. If a shorter time elapsed, no effect was noted with the ACTH protein, nor was any effect noted with an ACTH acid peptide mixture under the conditions employed.

3. Administration of epinephrine to normal or hypophysectomized rats, singly or in combination with ACTH protein (in which case its effect was potentiated), produced a significant reduction in the number of thoracic duct lymphocytes. This effect was not observed in the adrenalectomized rat, suggesting that epinephrine may act directly in producing this effect.

4. Growth hormone (beef anterior pituitary), Pitressin, Pitocin, Adrenal Cortex Extract, cortisone acetate, and desoxycorticosterone glucoside did not alter the levels of thoracic duct lymphocytes under the conditions of these experiments.