Augmentation of Arterial Hepatic and Renal Flow by Extracted and Synthetic Parathyroid Hormone

Abstract

In anesthetized dogs the arterial hepatic flowproper was calculated by subtracting gastroduodenal artery flow from hepatic artery flow, using probes from a sine wave electromagnetic flowmeter. Additionally, renal blood flow was measured. Using this technique, earlier evidence that parathyroid extract (PTE) augmented arterial hepatic and renal flow was confirmed. This information was valuable because in the earlier study the effects had been assessed only on celiac flow after extirpation of stomach, pancreas and/or spleen. Synthetic bovine parathyroid hormone, containing the first 34 amino acids was shown to have a similar effect as PTE. Thus, the hemodynamic action of PTE indeed was due to the same chemical entity that influences calcium metabolism. The augmentation of arterial hepatic flow (4–5-fold) was large, the dosage needed small (ED50 appr. 200 ng/kg, i.e., 0.6 IU/kg), the effect (maximum within 1 min) as well as the disappearance rate quick (return to 50% of the maximum obtainable within 15 min). (Endocrinology95: 621, 1974)