钙/钙调蛋白依赖性蛋白激酶的α亚基增强大鼠脊髓背角神经元的兴奋性氨基酸和突触反应。

Alpha subunit of calcium/calmodulin-dependent protein kinase enhances excitatory amino acid and synaptic responses of rat spinal dorsal horn neurons.

Kolaj M, Cerne R, Cheng G, Brickey D A, Randić M

Department of Veterinary Physiology and Pharmacology, Iowa State University, Ames 50011.

J Neurophysiol. 1994 Nov;72(5):2525-31. doi: 10.1152/jn.1994.72.5.2525.

Abstract

Here we report that in acutely isolated rat spinal dorsal horn (DH) neurons, the alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA)/kainate and N-methyl-D-aspartate (NMDA) receptors can be regulated by endogenous and exogenous calcium/calmodulin-dependent protein kinase II (CaM-KII). Intracellularly applied, the alpha-subunit of CaM-KII enhanced AMPA/kainate and NMDA currents recorded with the use of the whole cell patch-clamp technique. 2. Microcystin, a nonselective phosphatases inhibitor, also enhances AMPA and NMDA responses. 3. Conventional intracellular recordings were made from substantia gelatinosa neurons in spinal cord slices to determine the effect of intracellular application of CaM-KII on excitatory synaptic potentials evoked by electrical stimulation of primary afferent fibers. Excitatory synaptic transmission was enhanced by CaM-KII, which is consistent with the importance of phosphorylation of the postsynaptic AMPA/kainate and NMDA receptor-ion complexes in the short- and long-term changes in synaptic transmission.

摘要

在此我们报告，在急性分离的大鼠脊髓背角（DH）神经元中，α-氨基-3-羟基-5-甲基-4-异恶唑丙酸（AMPA）/海人藻酸和N-甲基-D-天冬氨酸（NMDA）受体可受内源性和外源性钙/钙调蛋白依赖性蛋白激酶II（CaM-KII）调控。在细胞内应用时，CaM-KII的α亚基增强了使用全细胞膜片钳技术记录的AMPA/海人藻酸电流和NMDA电流。2. 微囊藻毒素是一种非选择性磷酸酶抑制剂，它也增强AMPA和NMDA反应。3. 从脊髓切片的胶状质神经元进行传统的细胞内记录，以确定细胞内应用CaM-KII对初级传入纤维电刺激诱发的兴奋性突触电位的影响。CaM-KII增强了兴奋性突触传递，这与突触后AMPA/海人藻酸和NMDA受体-离子复合物的磷酸化在突触传递的短期和长期变化中的重要性相一致。