EVIDENCE FOR LIVER INACTIVATION OF PARATHYROID HORMONE1

Abstract

Parathyroid glands auto-transplanted to the hepatic portal circulation (spleen) failed to show hypertrophic changes. However, they were unable to maintain calcium levels of peritoneal lavage fluid equal to those held by normal controls or animals with auto-transplants in the peripheral circulation (testis). It is concluded that the lessened capacity of spleen-implanted parathyroids to mobilize calcium is due to partial inactivation of the hormone during its passage through the liver.