INFLUENCE OF TRANSPLANTATION OF PARATHYROID-GLANDS ON BLOOD-PRESSURE DEVELOPMENT IN STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS AND IN NORMOTENSIVE WISTAR KYOTO RATS

The influence of the parathyroid glands (PTG) on the development of high blood pressure (BP) in stroke prone spontaneously hypertensive (SHR/SP) and Wistar Kyoto (WKY) rats has been studied. After ablation of their own PTG's SHR/SP received PTG's from WKY rats and vice versa. After transplantation (TRPL) a normal calcium and parathyroid hormone (PTH) status was preserved during the whole observation period. One group of animals received a high salt diet (8% NaCl) for 4 weeks after transplantation, the other group received a normal rat chow for 3 months. In SHR/SP, which had PTG-transplants from WKY rats, the development of BP was clearly attenuated compared to sham operated rats in both experimental groups. WKY rats with PTG's from SHR/SP became hypertensive after two weeks during salt loading and after six weeks under normal diet. Sham operated WKY rats remained normotensive. The results demonstrate that the parathyroid gland is involved in the pathogenesis of hypertension, but the only known secretory product of PTG's, parathyroid hormone, seems not to be responsible for these effects.