Gil Mara, Zhen Xuechu, Friedman Eitan
Department of Physiology/Pharmacology, CUNY Medical School, 138th Street and Convent Avenue, New York, NY 10031, USA.
Neurosci Lett. 2003 Oct 9;349(3):143-6. doi: 10.1016/s0304-3940(03)00852-8.
Prenatal cocaine exposure in rabbits induces cerebrocortical structural abnormalities. Glycogen synthase kinase-3beta (GSK3beta) plays an important role in neuronal development and survival. This study was designed to examine the effect of prenatal cocaine on brain GSK3beta. Rabbits exposed in utero to cocaine and assessed on postnatal day 20 had increased basal levels of phospho-GSK3beta (ser-9) in frontal cortex (FCX) and striatum, but not hippocampus (HP). However, no changes in GSK3beta expression were detected in the brain regions of treated rabbits. Consistent with the change in GSK3beta activity, levels of beta-catenin, a downstream substrate of GSK3beta, increased in FCX but not in HP of cocaine offspring. Administration of a D(1) dopamine receptor agonist inhibited GSK3beta activity in FCX and HP of control rabbits but not in cocaine offspring. This loss of GSK3beta inhibition is in accord with the previously demonstrated dysfunction of this receptor in in utero cocaine-exposed animals. The results indicate that prenatal cocaine exposure alters GSK3beta pathway in select brain areas and may underlie the structural changes noted in these animals.
孕期可卡因暴露会导致兔脑皮质结构异常。糖原合酶激酶-3β(GSK3β)在神经元发育和存活中起重要作用。本研究旨在检测孕期可卡因对脑GSK3β的影响。子宫内暴露于可卡因的兔在出生后第20天接受评估,其额叶皮质(FCX)和纹状体中磷酸化GSK3β(ser-9)的基础水平升高,但海马体(HP)中未升高。然而,在接受治疗的兔的脑区中未检测到GSK3β表达的变化。与GSK3β活性的变化一致,GSK3β的下游底物β-连环蛋白的水平在可卡因暴露后代的FCX中升高,但在HP中未升高。给予D(1)多巴胺受体激动剂可抑制对照兔FCX和HP中的GSK3β活性,但对可卡因暴露后代无效。这种GSK3β抑制作用的丧失与先前在子宫内可卡因暴露动物中证明的该受体功能障碍一致。结果表明,孕期可卡因暴露会改变特定脑区的GSK3β信号通路,这可能是这些动物出现结构变化的基础。