Grassi F, Cossu G, Eusebi F
Istituto di Istologia ed Embriologia generale, Rome, Italy.
J Neurol Sci. 1988 Mar;84(1):77-86. doi: 10.1016/0022-510x(88)90176-1.
Single channel recording patch-clamp technique was used in the mouse to compare the acetylcholine (ACh)-induced channel behaviour between normal and dystrophic myotubes. While open time and slope conductance were equivalent, ACh-induced channel opening frequency was more than 4-fold reduced in dystrophic compared to normal myotubes. In addition, the steady-state phosphorylation of the ACh receptor (AChR), tested by immunoprecipitation of 32P-labeled cells, indicated that the alpha-subunit was more heavily phosphorylated in the dystrophic myotubes. We propose that the degree of alpha-subunit phosphorylation of the AChR, which parallels the reduced AChR-channel opening probability, determines desensitization of the AChR in dystrophic myotubes.
在小鼠中采用单通道记录膜片钳技术，比较正常和营养不良性肌管中乙酰胆碱（ACh）诱导的通道行为。虽然开放时间和斜率电导相当，但与正常肌管相比，营养不良性肌管中ACh诱导的通道开放频率降低了4倍以上。此外，通过对32P标记细胞进行免疫沉淀检测的乙酰胆碱受体（AChR）稳态磷酸化表明，营养不良性肌管中的α亚基磷酸化程度更高。我们认为，AChR的α亚基磷酸化程度与AChR通道开放概率降低平行，决定了营养不良性肌管中AChR的脱敏作用。
