Adam-Vizi V, Deri Z, Vizi E S, Sershen H, Lajtha A
2nd Institute of Biochemistry, Semmelweis University of Medicine, Budapest, Hungary.
J Neurochem. 1991 Jan;56(1):52-8. doi: 10.1111/j.1471-4159.1991.tb02561.x.
The effect of 2-(4-phenylpiperidino)cyclohexanol (AH5183 or vesamicol), a compound known to block the uptake of acetylcholine (ACh) into cholinergic synaptic vesicles, on the release of endogenous and [14C]ACh from slices of rat striatum was investigated. ACh release was evoked either by electrical stimulation or by veratridine. The effect of electrical stimulation was entirely dependent on external Ca2+. By contrast, veratridine (40 microM) also enhanced ACh release in the absence of Ca2+. Indeed, with veratridine two components were clearly distinguished: one dependent on external Ca2+ and the other not. Vesamicol inhibited [14C]ACh release evoked by both veratridine and electrical stimulation in the presence of external Ca2+, provided it was added to the tissue prior to loading with [14C]choline. With the same treatment vesamicol only slightly affected the release of endogenous ACh. Under the same conditions the Ca2(+)-independent [14C]ACh release evoked by veratridine was not prevented by vesamicol. The differential responsiveness to vesamicol suggests that ACh pools involved in Ca2+o-dependent ACh release are different from those mobilized during Ca2+o-independent ACh release.
研究了2-(4-苯基哌啶基)环己醇（AH5183或维生米可）对大鼠纹状体切片中内源性乙酰胆碱（ACh）和[14C]ACh释放的影响，该化合物已知可阻断ACh摄取到胆碱能突触小泡中。通过电刺激或藜芦碱诱发ACh释放。电刺激的作用完全依赖于细胞外Ca2+。相比之下，藜芦碱（40 microM）在无Ca2+的情况下也能增强ACh释放。实际上，对于藜芦碱，可清楚区分出两个成分：一个依赖于细胞外Ca2+，另一个则不依赖。在存在细胞外Ca2+的情况下，若在向组织中加载[14C]胆碱之前加入维生米可，则它会抑制由藜芦碱和电刺激诱发的[14C]ACh释放。采用相同处理时，维生米可仅轻微影响内源性ACh的释放。在相同条件下，维生米可不能阻止藜芦碱诱发的不依赖Ca2+的[14C]ACh释放。对维生米可的不同反应性表明，参与依赖细胞外Ca2+的ACh释放的ACh池与在不依赖细胞外Ca2+的ACh释放过程中动员的ACh池不同。
