Moskowitz A S, Goodman R R
Brain Res. 1985 Dec 23;360(1-2):108-16. doi: 10.1016/0006-8993(85)91226-0.
The recent development of in vitro autoradiography techniques has enabled investigators to determine the distribution and relative levels of multiple ligand binding sites in discrete anatomical areas. In this study we used semi-quantitative in vitro autoradiography to compare the levels of binding to central mu1, mu2, and delta opioid sites in two strains of mice, C57BL/6BY and CXBK. The CXBK strain is known to be deficient in whole brain opioid binding sites and to be less sensitive than the C57 strain to the analgesic and locomotor stimulatory effects of opiates and opioids. Delta sites were visualized using [3H](D-Ala2-D-Leu5]-enkephalin (DADL) plus a low concentration of morphine, total mu sites (mu1 and mu2) were visualized using [3H] dihydromorphine (DHM), and mu2 sites were visualized using [3H]DHM plus a low concentration of DADL. Binding to mu1 sites was determined by subtracting mu2 binding from total mu binding. We found that the two strains did not consistently differ in the levels of delta site; in some areas the CXBKs had lower levels but in many areas they had levels equal to or greater than those for the C57s. The CXBK strain, however, either had less or the same amount of mu binding as the C57 strain in all areas studied. The CXBK strain was especially deficient in mu1 binding, particularly in areas involved in pain processing.
体外放射自显影技术的最新发展使研究人员能够确定离散解剖区域中多个配体结合位点的分布和相对水平。在本研究中，我们使用半定量体外放射自显影技术比较了两种小鼠品系C57BL/6BY和CXBK中与中枢μ1、μ2和δ阿片样物质位点的结合水平。已知CXBK品系全脑阿片样物质结合位点缺乏，且比C57品系对阿片类药物和阿片样物质的镇痛及运动刺激作用敏感性更低。使用[3H](D-丙氨酸2-D-亮氨酸5]脑啡肽（DADL）加低浓度吗啡来显示δ位点，使用[3H]二氢吗啡（DHM）来显示总μ位点（μ1和μ2），使用[3H]DHM加低浓度DADL来显示μ2位点。通过从总μ结合中减去μ2结合来确定与μ1位点的结合。我们发现，这两个品系在δ位点水平上并非始终存在差异；在某些区域，CXBK品系的水平较低，但在许多区域，它们的水平等于或高于C57品系。然而，在所有研究区域中，CXBK品系的μ结合量要么比C57品系少，要么与C57品系相同。CXBK品系在μ1结合方面尤其缺乏，特别是在参与疼痛处理的区域。
