卡巴胆碱和单胺对猪脑微小组织中肌醇磷脂分解的刺激作用：钾离子的影响

Stimulation of inositol phospholipid breakdown in pig brain miniprisms by carbachol and monoamines: effect of K+.

Tiger G, Björklund P E, Fowler C J

Department of Pharmacology, University of Umeå, Sweden.

Int J Biochem. 1989;21(2):157-63. doi: 10.1016/0020-711x(89)90104-3.

Abstract

The effects of carbachol, monoamines and K+ upon the rate of inositol phospholipid breakdown in pig brain miniprisms have been investigated. 2. In the striatum, carbachol (EC50 approx. 1 microM) and noradrenaline (EC50 approx. 25 microM) stimulated inositol phospholipid breakdown, whereas 5-hydroxytryptamine (1-1000 microM) was without effect. 3. The rate of inositol phospholipid breakdown was increased by raising the assay [K+] to greater than or equal to 40 mM. In the hippocampus and hypothalamus, a synergistic effect between K+ and carbachol was noted, whereas in the striatum, the effects were additive. 4. In striatal and hippocampal miniprisms, dopamine also increased inositol phospholipid breakdown, albeit only at high (greater than or equal to 1 mM) concentrations. Dopamine (1 mM) reduced the stimulation produced by noradrenaline (1 mM), suggesting that the effect of dopamine is due to a weak noradrenergic action of this catecholamine.

摘要

已经研究了卡巴胆碱、单胺和钾离子对猪脑薄片中肌醇磷脂分解速率的影响。2. 在纹状体中，卡巴胆碱（半数有效浓度约为1微摩尔）和去甲肾上腺素（半数有效浓度约为25微摩尔）刺激肌醇磷脂分解，而5-羟色胺（1 - 1000微摩尔）则无作用。3. 将测定的钾离子浓度提高到大于或等于40毫摩尔时，肌醇磷脂分解速率增加。在海马体和下丘脑，观察到钾离子和卡巴胆碱之间有协同作用，而在纹状体中，二者的作用是相加的。4. 在纹状体和海马体薄片中，多巴胺也增加肌醇磷脂分解，尽管仅在高浓度（大于或等于1毫摩尔）时才起作用。多巴胺（1毫摩尔）减弱了去甲肾上腺素（1毫摩尔）产生的刺激作用，表明多巴胺的作用是由于这种儿茶酚胺的微弱去甲肾上腺素能作用。