Manning B H, Morgan M J, Franklin K B
Department of Psychology, McGill University, Montreal, Quebec, Canada.
Neuroscience. 1994 Nov;63(1):289-94. doi: 10.1016/0306-4522(94)90023-x.
A mapping study was performed to determine where in the rat brain morphine acts to produce analgesia in the formalin test, which is an animal model of prolonged pain associated with tissue injury. A single dose (5 nmol) of morphine was bilaterally microinjected into a wide range of brain areas throughout the midbrain and forebrain. Strong analgesia was elicited from the posterior hypothalamic area, the periaqueductal gray and ventral tegmental area. Other sites from which analgesia was elicited were the nucleus accumbens and a few sites in the retrorubral field and caudate-putamen. Analgesia from the periaqueductal gray or nucleus accumbens was accompanied by decreased locomotor activity and catalepsy, whereas analgesia from the posterior hypothalamic area or ventral tegmentum was accompanied by a noticeable increase in locomotor activity and rearing. Morphine into various thalamic nuclei had no effect. These results indicate that the primary sites of action of morphine in the formalin test are probably the posterior hypothalamic area and periaqueductal gray, with an additional contribution from regions innervated by tegmental dopamine cells.
进行了一项定位研究，以确定在福尔马林试验中大鼠脑内吗啡产生镇痛作用的部位，福尔马林试验是一种与组织损伤相关的持续性疼痛的动物模型。将单剂量（5纳摩尔）的吗啡双侧微量注射到整个中脑和前脑的广泛脑区。在下丘脑后区、导水管周围灰质和腹侧被盖区可引发强烈的镇痛作用。其他引发镇痛作用的部位有伏隔核以及红核后区和尾状核-壳核中的一些部位。导水管周围灰质或伏隔核引起的镇痛作用伴有运动活动减少和僵住，而下丘脑后区或腹侧被盖区引起的镇痛作用则伴有运动活动和竖毛明显增加。将吗啡注入各种丘脑核团没有效果。这些结果表明，在福尔马林试验中吗啡的主要作用部位可能是下丘脑后区和导水管周围灰质，被盖多巴胺能细胞支配的区域也有额外作用。
