吗啡及第二信使对鼠脑细胞膜蛋白质磷酸化的调节

 本文研究了几种蛋白激酶活化剂及吗啡对脑细胞膜蛋白质磷酸化的调节。cAMP刺激了一种68KDa蛋白质和几种60KDa相关的蛋白质的磷酸化作用,Ca~(++)刺激68KDa和50KDa蛋白质的磷酸化。μ吗啡受体的特异性兴奋剂D-脑啡肽(DAGO)增加68KDa蛋白质的磷酸化,而吗啡K受体的特异性兴奋剂,Bremazocyne抑制这一蛋白质的磷酸化。蛋白激酶c的特异性活化剂——磷脂酰丝氨酸(PS)和甘油二油酸酯(DO)不促进这一磷酸化。相反,却抑制cAMP、Ca~(++)、和DAGO所刺激的68KDa蛋白质的磷酸化。结果表明,在鼠脑细胞膜存在一种68KDa专一的蛋白激酶,其活性受吗啡及几种细胞内信使分子,如cAMP、Ca~(++)和DO的调节。

REGULATION OF PROTEIN PHOSPHORYLATION IN RAT BRAIN MEMBRANE BY OPIOIDS AND SECOND MESSENGERS IN VITRO

The effects of various protein kinase activators and opioids on protein phosphorylation in rat brain membrane were studied.cAMP stimulated phosphorylation of a 68 KDa and several related proteins of 60 KDa, and calcium stimulated the phosphorylation of the 68KDa and a 50KDa proteins. The μ, opioid receptor specific agonists, for example,D-Ala2 or MePh4-Gly-ol5-enkephalin (DAGO) increased the phosphorylation of 68KDa protein, where as the K opioid receptor specific agonist, bremazocyne, inhibited the same reaction. The specific activators of protein kinase C, phosphatidylserine (PS) and diolein (DO) showed no stimulation on phosphorylation. In contrast, these lipids inhibited the cAMP, calcium and DAGO stimulated phosphorylation of 68KDa protein.Results suggest that in rat brain membranes there is a 68 KDa protein specific protein kinase,whose acitivity may be regulated by opioids and various intra-cellular messenger molecules such as cAMP, calcium and DO.