AIM DDT1 MF-2 hamster smooth muscle cells were used to investigate the role of α1B-adrenoceptor (AR) in the cell proliferation and its signaling pathway. METHODS DNA synthesis was measured by ［3H］thymidine (TdR) incorporation and the cell cycle was determined by flow cytometry. The actions of several inhibitors and activators of second messenger on NE-induced DNA synthesis were investigated. RESULTS NE (0.1～1 μmol*L-1) elicited significant concentration-dependent stimulation of DDT1 MF-2 cell proliferation. The proliferative effect caused by α1B-AR was blocked by PLC inhibitor (U73122, 10 μmol*L-1), Ca2+/ATPase inhibitor (cyclopiazonic acid, 10 μmol*L-1), intracellular Ca2+ chelator (BAPTA/AM, 10 μmol*L-1), PKC inhibitors (RO-31-8220, 0.1 μmol*L-1 and calphostin C, 0.1 μmol*L-1), TK inhibitors (tyrphostin A25, 10 μmol*L-1 and genistein, 10 μmol*L-1), and MEK1/2 inhibitor (PD 98059, 10 μmol*L-1). CONCLUSION α1B-AR subtypes stimulate DDT1 MF-2 cells growth and its signal pathway is related to the PLC activation、Ca2+ release、PKC、TK and ERKs activation.%目的研究激动α1B-肾上腺素受体(α1B-AR)对DDT1 MF-2细胞生长的影响及其机制。方法用3H-胸腺嘧啶参入法测定细胞的DNA合成速率；用流式细胞计测定细胞周期。结果去甲肾上腺素(NE,0.1～1 μmol*L-1)可刺激DDT1 MF-2细胞DNA的合成。磷脂酶C 抑制剂(U73122,10 μmol*L-1)、Ca2+/ATP酶抑制剂(CPA,10 μmol*L-1)、胞内Ca2+络合剂(BAPTA/AM,10 μmol*L-1)、PKC抑制剂(RO-31-8220,0.1 μmol*L-1或calphostin C, 0.1 μmol*L-1)、酪氨酸激酶抑制剂(tyrphostin A25, 10 μmol*L-1或genistein,10 μmol*L-1)、MEK1/2抑制剂(PD 98059,10 μmol*L-1)均可阻断NE刺激细胞DNA合成的作用。结论激动α1B-AR可刺激DDT1 MF-2细胞增殖，其信号转导途径可能与PLC激活、Ca2+释放、PKC、TK和ERKs的激活有关。
展开▼
