[Effect of tetrandrine on calmodulin activity of lung tissue in rats with hypoxic pulmonary hypertension].
OBJECTIVE
The mechanism that tetrandrine (Tet) reduces hypoxic pulmonary hypertension was investigated


METHODS
30 Wistar rats were divided into normal control group, pulmonary hypertension group and tetrandrine-treated group. Total calcium conteins and calmodulin activity in lung tissue were measured with atomic absorption spectrophotometry and phosphodiesterase method.


RESULTS
The results showed that Tet could remarkably reduce the mean pulmonary artery pressure and pulmonary vascular resistance in rats with hypoxic pulmonary hypertension, the contents of calcium (62 +/- 10 umol.g-1) and calmodulin (20 +/- 4 ng.mg-1) in the lung were significantly lower in rats administrated with Tet than those (74 +/- 16 umol.g-1, 27 +/- 6 ng.mg-1) rats with hypoxic pulmonary hypertension, and the contents of calcium were related with the mean pulmonary artery pressure and pulmonary vascular resistance in the lung administrated with Tet.


CONCLUSIONS
The results indicated the mechanism that tetrandrine effectively reduces hypoxia pulmonary hypertension may be associated with decreasing intracellular calcium concentration in vascular smooth cells, and the effect may be a result of anti-calmodulin activity.
Li
W
W
Department of Internal Medicine, First Affiliated Hospital of West China University of Medical Sciences, Chengdu.
Chen
W
W
Wu
Z
Z
D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D044182:Benzylisoquinolines; D001794:Blood Pressure / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002147:Calmodulin / Q000378:metabolism*; D006976:Hypertension, Pulmonary / Q000378:metabolism*; D000860:Hypoxia / Q000150:complications; D008168:Lung / Q000378:metabolism; D008297:Male; D011651:Pulmonary Artery / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D014655:Vascular Resistance / Q000187:drug effects
D000470:Alkaloids; D044182:Benzylisoquinolines; D002121:Calcium Channel Blockers; D002147:Calmodulin; C009438:tetrandrine; D002118:Calcium