Koskinen L O, Bill A
Acta Physiol Scand. 1983 Nov;119(3):235-41. doi: 10.1111/j.1748-1716.1983.tb07333.x.
Effects of morphine and naloxone were investigated on cerebral, ocular and peripheral blood flow in unanesthetized rabbits. Blood flow measurements were performed with the labelled microsphere method. Cervical sympathotomy was performed on one side the day before the flow determination. Naloxone 2 mg/kg b.w. i.v. had no consistent effect on cerebral, ocular or peripheral blood flow or on mean arterial blood pressure. Morphine 2 mg/kg b.w. i.v. caused a rise in PaCO2 of 0.9 kPa and tended to increase cerebral blood flow in all parts investigated. In the hippocampal region, caudate nucleus and collicles the increase in flow was about 30% which is more than expected from the rise in PaCO2. Blood flow in the retina increased while the other parts of the eye showed no consistent changes in blood flow. Morphine reduced the blood flow in the duodenum by 60%. Mean arterial blood pressure did not change after morphine. No effect of the cervical sympathotomy was detected on cerebral or ocular blood flow before or after morphine or naloxone. Thus, we found no evidence for a tonically operating opioid system controlling cerebral, ocular or peripheral blood flow. However, exogenously administrated opiate can influence blood flows in these areas.
研究了吗啡和纳洛酮对未麻醉家兔脑、眼及外周血流的影响。采用放射性微球法进行血流测量。在血流测定前一天，对一侧进行颈交感神经切断术。静脉注射2mg/kg体重的纳洛酮对脑、眼或外周血流以及平均动脉血压没有持续影响。静脉注射2mg/kg体重的吗啡使动脉血二氧化碳分压升高0.9kPa，并倾向于增加所有研究部位的脑血流量。在海马区、尾状核和丘脑中，血流量增加约30%，这比动脉血二氧化碳分压升高所预期的要多。视网膜血流量增加，而眼的其他部位血流量没有一致变化。吗啡使十二指肠血流量减少60%。注射吗啡后平均动脉血压未改变。在注射吗啡或纳洛酮之前或之后，未检测到颈交感神经切断术对脑或眼血流有影响。因此，我们没有发现存在一个持续起作用的阿片样物质系统控制脑、眼或外周血流的证据。然而，外源性给予阿片类药物可影响这些区域的血流。
