Falardeau P, Bédard P J, Di Paolo T
School of Pharmacy, Laval University, Québec, Canada.
Neurosci Lett. 1988 Mar 31;86(2):225-9. doi: 10.1016/0304-3940(88)90575-7.
The relationship between dopamine (DA), dihydroxyphenylacetic acid (DOPAC) or homovanillic acid (HVA) concentrations and [3H]spiperone binding to D2 DA receptors in caudate nucleus, putamen and nucleus accumbens following DAergic lesion with MPTP in monkeys was investigated. The level of DA depletion varied from 37% to 100% while a mean elevation in [3H]spiperone binding density of 114.8 +/- 4.7% of control (P less than 0.01) was observed when DA depletion was at least 90% of control values. A logarithmic correlation (y = -7.19 In x +111.15; r = -0.54, P less than 0.01) between DA concentrations (x) and the density of [3H]spiperone binding sites (y) was observed in all brain regions. The correlation between DOPAC or HVA concentrations and [3H]spiperone binding was best represented by linear rather than logarithmic equations. These results indicate that supersensitivity of DA receptors develops after MPTP lesion in monkeys when the number of remaining nerve fibers becomes too few to compensate for the DA loss.
研究了用1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）对猴子进行多巴胺能损伤后，尾状核、壳核和伏隔核中多巴胺（DA）、二羟基苯乙酸（DOPAC）或高香草酸（HVA）浓度与[3H]螺哌隆与D2多巴胺受体结合之间的关系。多巴胺耗竭水平从37%到100%不等，当多巴胺耗竭至少达到对照值的90%时，观察到[3H]螺哌隆结合密度平均升高至对照值的114.8±4.7%（P<0.01）。在所有脑区均观察到多巴胺浓度（x）与[3H]螺哌隆结合位点密度（y）之间呈对数相关性（y = -7.19 In x +111.15；r = -0.54，P<0.01）。DOPAC或HVA浓度与[3H]螺哌隆结合之间的相关性最好用线性方程而非对数方程表示。这些结果表明，当剩余神经纤维数量过少无法补偿多巴胺损失时，猴子在MPTP损伤后会出现多巴胺受体超敏反应。
