Weihmuller F B, Bruno J P
Department of Psychology, Ohio State University, Columbus 43210.
Behav Brain Res. 1989 Nov 1;35(2):95-109. doi: 10.1016/s0166-4328(89)80110-x.
The role of brain dopamine (DA) in the control of sensorimotor function was studied in normal rat pups and in animals depleted of DA at various stages of development. Acute administration of the DA antagonist haloperidol produced akinesia and catalepsy in normal pups as early as 3 days of age and resulted in impaired orientation to somatosensory stimulation by 15 days of age. In contrast, near-total depletions of striatal DA incurred on day 3, 15, or 20 produced no obvious deficits in sensorimotor function either soon after the depletion or after the animals reached adulthood. Rats depleted of DA on day 27 exhibited akinesia, catalepsy, and sensory neglect. These deficits resembled those seen in comparably depleted adults except that they were more transient, lasting 1 week rather than 4-5 weeks. Moreover, while rats depleted as adults became akinetic and cataleptic after the stress of a cold water swim, animals depleted on day 27 did not. These findings demonstrate that DA is involved in sensorimotor function during early development. The data also reveal an impressive degree of plasticity in the neural controls of sensorimotor function and that the extent of this plasticity is dependent upon the age at the time of damage.
在正常幼鼠以及在发育各阶段多巴胺（DA）耗竭的动物中，研究了脑多巴胺在感觉运动功能控制中的作用。早在3日龄时，给正常幼鼠急性注射多巴胺拮抗剂氟哌啶醇就会产生运动不能和僵住症，到15日龄时会导致对体感刺激的定向能力受损。相比之下，在第3、15或20天造成纹状体多巴胺近乎完全耗竭，在耗竭后不久或动物成年后，感觉运动功能均未出现明显缺陷。在第27天耗竭多巴胺的大鼠表现出运动不能、僵住症和感觉忽视。这些缺陷与在多巴胺同等程度耗竭的成年大鼠中所见的缺陷相似，只是它们更短暂，持续1周而非4 - 5周。此外，成年后耗竭多巴胺的大鼠在冷水游泳应激后会变得运动不能和僵住，而在第27天耗竭多巴胺的动物则不会。这些发现表明，多巴胺在早期发育过程中参与感觉运动功能。数据还揭示了感觉运动功能的神经控制中存在令人印象深刻的可塑性程度，并且这种可塑性的程度取决于损伤发生时的年龄。
