MOLECULAR MECHANISM OF ADENYLYL CYCLASE SUPERACTIVATION

腺苷酸环化酶超激活的分子机制

• 批准号: 6838749
• 负责人: HENRY I YAMAMURA
• 金额: $ 26.66万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6838749
• 关键词: MOLECULAR; MECHANISM; ADENYLYL; CYCLASE; SUPERACTIVATION

EXCEED THE SPACE PROVIDED. Analgesics that act through the 5 opioid receptor have low addictive potential but similarly to classical opiates, display tolerance after long-term treatment. Chronic opioid receptor stimulation leads to a compensatory increase in adenylyl cyclase (AC) activity, called AC superactivation. We have demonstrated that an AC isoenzyme (AC VI) is phosphorylated upon chronic 5opioid agonist (SNC 80) treatment in CHO cells transfected with the human 8 opioid receptor (hDOPJCHO). We hypothesize that phosphorylation of AC VI is involved in adenylyl cyclase superactivation, and that superactivation is involved in tolerance to chronic 8 opioid agonists. In preliminary experiments we found that o_-transducin, a putative scavenger of G protein 133,- subunits, attenuated both chronic SNC 80 mediated phosphorylation of AC VI and AC superactivation. In this proposal we will use other, independent methods, to study the involvement of G protein 133,-subunitsin cellular responses to acute- and chronic SNC 80 treatment. Attenuation of AC superactivation and AC VI phosphorylation by these methods will confirm the role of G protein 133,-subunitsin chronic SNC 80-mediated respolises. Subsequently we will show that free 133,-subunitsr,eleased upon chronic SNC 80 treatment, regulate the activity of second messenger regulated protein kinases and Raf-1 protein kinase in hDOR/CHO cells. Finally, we will demonstrate that depletion of the protein kinase responsible for phosphorylation of AC VI in hDOR/CHO cells also attenuates chronic 8 opioid agonist mediated AC superactivation. Better understanding of the molecular mechanisms of drug tolerance at the human 5 opioid receptor should aid in the development of longer acting analgesics with fewer side effects. PERFORMANCE SITE ========================================Section End===========================================

超过提供的空间。通过5种阿片类药物受体起作用的镇痛药具有低成瘾的潜力，但与古典鸦片类似，长期治疗后显示耐受性。慢性阿片类药物受体刺激导致腺苷环酶（AC）活性的补偿性增加，称为AC超激活。我们已经证明，在用人8阿片类受体（HDOPJCHO）转染的CHO细胞中，在慢性5PIOED激动剂（SNC 80）治疗中磷酸化AC同工酶（AC VI）。我们假设AC VI的磷酸化参与腺苷酸环化酶超活化，并且超激活与对慢性8阿片类药物激动剂的耐受性有关。在初步实验中，我们发现O_-Transducin是G蛋白133的推定的清除剂， - 亚基，均衰减了慢性SNC 80介导的AC VI的磷酸化和AC超级激活。在此提案中，我们将使用其他独立的方法来研究G蛋白133，-subunitsin细胞对急性和慢性SNC 80治疗的参与。通过这些方法对AC超活化和AC VI磷酸化的衰减将证实G蛋白133，-subunitsin慢性SNC 80介导的重新溶解的作用。随后，我们将表明，在慢性SNC 80治疗后解雇的自由133，-subunitsr调节了HDOR/CHO细胞中第二信使调节的蛋白激酶和RAF-1蛋白激酶的活性。最后，我们将证明，HDOR/CHO细胞中负责AC VI磷酸化的蛋白激酶的耗竭也减弱了慢性8阿片类动力学介导的AC超激活。更好地理解人5阿片受体对药物耐受性的分子机制，应有助于发展较少副作用的较长作用镇痛药。表演站点=============================================================================================