Maximov G V, Revin V V, Grunyushkin I P, Kols O R
School of Biology, Lomonosov Moscow State University, Moscow, 119899, Russia.
Biochemistry (Mosc). 2000 Apr;65(4):431-5.
Axon excitation increases the number of acetylcholine receptors (ACR) of the Schwann cell (SC) depending on the frequency of rhythmic excitation (RE) and on intercellular concentrations of K+, Ca2+, and acetylcholine. During RE, activity of axonal acetylcholine esterase is decreased, thus providing for high intercellular acetylcholine concentration. Increased intercellular concentration of acetylcholine activates phosphoinositide-specific phospholipase C (PIPLC) of the myelin nerve fiber. During RE, K+ depolarization and acetylcholine exocytosis can activate Ca2+ entry via Ca2+ channels, thus inducing SC ACR phosphorylation mediated by PIPLC stimulation.
轴突兴奋会根据节律性兴奋（RE）的频率以及细胞间钾离子（K⁺）、钙离子（Ca²⁺）和乙酰胆碱的浓度增加施万细胞（SC）的乙酰胆碱受体（ACR）数量。在节律性兴奋期间，轴突乙酰胆碱酯酶的活性降低，从而使细胞间乙酰胆碱浓度升高。细胞间乙酰胆碱浓度的增加会激活髓鞘神经纤维的磷酸肌醇特异性磷脂酶C（PIPLC）。在节律性兴奋期间，K⁺去极化和乙酰胆碱胞吐作用可通过Ca²⁺通道激活Ca²⁺内流，从而诱导由PIPLC刺激介导的施万细胞ACR磷酸化。
