[Role of thymocytes in the correlation between the thymus and hypophysis]

The influence of the thymus on the growth hormone (GH) level in the mouse hypophysis has been studied. It has been found, that syngeneic transfer of thymocytes of young mice into thymectomized mice causes on increase of the growth hormone level in the hypophysis. Administration of hydrocortisone simultaneously with transfer of thymocytes accelerated the GH level increase. The administration of only hydrocortisone into thymectomized mice does not lead to changes in the GH level. The increased GH level was observed when thymocytes were replaced by some structures shedding from thymocytes after their stimulation with short peptide thymic hormone. It is supposed that thymocytes can stimulate GH accumulation in the hypophysis.