Effect of bovine parathyroid hormone 1-34 0n calcium flux and 6-keto-PGF1a release of rabbit aorta

The vasoactive mechanism of bovine parathyroid hormone l-34 (bPTHl-34) was investigated as compared with nifedipine and verapamil. bPTHl-34 inhibited significantly 45Ca influx of rabbit aorta through potential sensitive channel opened by high potassium (KC1 145 mmol/L group 360+74 nmol/g wet tissue, KCI 145 mmol/L +bPTHl-34 0.12 ymoj/L group 275 + 50 nmol/g wet tissue, n = 4, P<0.05) and BAY k-8644 (BAY k-8644 0.14 ymol/L group 302 + 41 nmol/g wet tissue, BAY k-8644 0.14 vmol/L + bPTHl-34 0.12 vmol/L group 190+40 nmol/g wet tissue, n=4, P0.05). It is suggested that there is no relationship between metabolism of PGI, and vasodilation of bPTHl-34.