FUNCTIONAL OF CaィイD12+ィエD1-Calmodulin sensitive a denylate cyclase in central neurons

CaD12+D1-钙调蛋白对中枢神经元否认环化酶敏感的功能

基本信息

批准号：
10470009
负责人：
AKAIKE Norio
金额：
$ 6.85万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

To explore the intracellular pathways activated by vasopressin receptors, the effects of arginine vasopressin (AVP) and its analogs mediating glycine (Gly)-induced Cl- currents (lィイD2GlyィエD2) were examined in acutely dissociated rat hoppocampal CA1 neurons using the while-cell patch recording technique. AVP and its analogs inhibited lィイD2GlyィエD2 in a concentration-dependent manner. The inhibitory actions of AVP (4-9) [AVP metabolite] and NC-1900 [AVP (4-9) analog] were reversed by a VィイD21ィエD2 receptor antagonist, or pretreatment with BAPTA-AM. In contrast, these blocking procedures had no effect on the DDAVP [VィイD22ィエD2 agonist] action. A VィイD22ィエD2 receptor antagonist did not block the inhibitory action of AVP(4-9) or NC-1900, but blocked that of DDAVP. The inhibitory action of AVP was completely blocked by the co-application of the VィイD21ィエD2 and VィイD22ィエD2 antagonists. The inhibitory action of NC-1900 was not affected by perfusion with a CaィイD12+ィエD1-free external solution, but was strongly blocked by thapsigargin. The intercellular application of heparin of anti-IPィイD23ィエD2 also blocked the NC-1900 action. Furthermore, CaィイD12+ィエD1/calmodulin (CaM) inhibitors blocked the NC-1900 action, while a Cam-dependent kinase II inhibitor and PKC modulators had no effect. 2', 5'-Dideoxyadenosine, an adenylate cyclase inhibitor, H-89 and Rp-cAMPS blocked the inhibitory actions of NC-1900 and DDAVP. These results suggest that the activation of the VィイD21ィエD2 receptor in the hippocampal neurons induces the production of IPィイD23ィエD2 which releases CaィイD12+ィエD1 from the IPィイD23ィエD2-sensitive CaィイD12+ィエD1 storage sites. The CaィイD12+ィエD1 binds to CaM, resulting in the activation of CaィイD12+ィエD1/CaM-sensitive adenylate cyclases. The activation of PKA through the adenylate cyclase inhibits lィイD2GlyィエD2.

为了探索加压素受体激活的细胞内通路，使用 while-cell patch 记录在急性分离的大鼠海马 CA1 神经元中检查精氨酸加压素 (AVP) 及其类似物介导甘氨酸 (Gly) 诱导的 Cl-电流 (LYD2GlyD2) 的作用AVP 及其类似物以浓度依赖性方式抑制 D2GlyD2。 AVP (4-9) [AVP 代谢物] 和 NC-1900 [AVP (4-9) 类似物] 的抑制作用可被 D21D2 受体拮抗剂或 BAPTA-AM 预处理逆转，相反，这些阻断程序没有作用。对 DDAVP [D22D2 激动剂] 作用的影响 D22D2 受体拮抗剂不会阻断 DDAVP 的抑制作用。 AVP(4-9) 或NC-1900，但阻断DDAVP 的抑制作用被VD21D2 和VD22D2 拮抗剂的共同应用完全阻断，NC-1900 的抑制作用不受灌注的强烈影响。无CaiD12+D1的外用溶液，但被毒胡萝卜素阻断。抗IPD23D2的肝素也阻断NC-1900作用此外，CaM D12+D1/钙调蛋白(CaM)抑制剂阻断NC-1900作用，而Cam依赖性激酶II抑制剂和PKC调节剂没有作用。 5'-双脱氧腺苷，一种腺苷酸环化酶抑制剂，H-89 和 Rp-cAMPS 被阻断NC-1900 和 DDAVP 的抑制作用表明，海马神经元中 ViD21D2 受体的激活会诱导 IPD23D2 的产生，从而从 IPD23D2 敏感的 CaD12+D1 储存位点释放 CaD12+D1。到 CaM，导致CaD12+D1/CaM 敏感腺苷酸环化酶的激活通过腺苷酸环化酶激活 PKA 抑制 lyD2GlyD2。