ABSTRACT
AIM:To observe the role of calcium-sensing receptor (CaSR) in the regulation of pulmonary artery tension.METHODS:The intracellular calcium concentration ([Ca2+]i) was detected by laser-scanning confocal micros-copy, and the pulmonary artery tension was determined by the pulmonary arterial ring technique .RESULTS: Increased levels of [Ca2+]o or Gd3+(an agonist of CaSR) induced the increase in [Ca2+]i and pulmonary artery constriction in a concentration-dependent manner.Additionally, the effects of Ca2+and Gd3+were inhibited by U73122 and D609 (specific inhibitor of PLC), and 2-APB and heparin (specific antagonist of IP3 receptor).However, U73343 (U73122 inactive ana-logue) did not take effect.CONCLUSION: CaSR may be involved in the regulation of pulmonary artery tension by in-creasing [Ca2+]i through G-protein-PLC-IP3 pathway.
