Brorson J R, Bleakman D, Chard P S, Miller R J
Department of Pharmacological and Physiological Sciences, University of Chicago, Illinois 60637.
Mol Pharmacol. 1992 Apr;41(4):603-8.
In cultures of rat cerebellar neurons that were enriched in Purkinje cells, the non-N-methyl-D-aspartate glutamate receptor agonist kainate (KA) stimulated Ca2+ influx into all neurons in Na(+)-containing solutions. A large Ca2+ influx was also observed in most neurons when KA was applied in Na(+)-free solutions, even when the cells were voltage-clamped at negative potentials. KA also stimulated Co2+ uptake into both Purkinje and non-Purkinje neurons. The KA-induced Ca2+ influx was insensitive to pharmacological antagonists of voltage-sensitive Ca2+ channels and antagonists of N-methyl-D-aspartate receptors. Thus, different types of cerebellar neurons possess KA-gated ionophores that are permeable to Ca2+. This Ca2+ conductance may play an important role in glutamate-mediated physiological and pathological events in the cerebellum.
在富含浦肯野细胞的大鼠小脑神经元培养物中，非N-甲基-D-天冬氨酸谷氨酸受体激动剂海藻酸（KA）在含Na⁺的溶液中刺激Ca²⁺流入所有神经元。当在无Na⁺的溶液中应用KA时，即使细胞在负电位下进行电压钳制，大多数神经元中也观察到大量Ca²⁺流入。KA还刺激Co²⁺摄入浦肯野神经元和非浦肯野神经元。KA诱导的Ca²⁺流入对电压敏感性Ca²⁺通道的药理拮抗剂和N-甲基-D-天冬氨酸受体的拮抗剂不敏感。因此，不同类型的小脑神经元拥有对Ca²⁺通透的KA门控离子载体。这种Ca²⁺电导可能在小脑谷氨酸介导的生理和病理事件中起重要作用。
