【Abstract】 In vitro,the effect of dailyzed plasma including parathyroid hypertensive factor (PHF) from SHR and parathyroid hormone (PTH) on 45Ca2+ uptake by vascular tissue was studied in the SD rats tail arteries incubated in the presence of Krebs-Heinsleit (K-H) buffer. The results showed that PHF significant increased 45Ca2+ uptake (3.90±0.56, n=12, P<0.001), but PTH significantly decreased 45Ca2+ uptake (1.08±0.51, n=16, P<0.001) as compared to control (2.20±0. 53, n=12). Increased doses of PTH resulted in decreasing of 45Ca2+uptake. The pressor mechanism of PHF may be due to stimulating calcium channel in smooth muscle cells,increasing 45Ca2+uptake and intracellular calcium in vascular tissues,whereas PTH acts as calcium antagonist,thereby reducing intracellular calcium level, expanding vascular vessels and decreasing blood pressure.更多还原