Bekkers J M, Richerson G B, Stevens C F
Salk Institute, Howard Hughes Medical Institute, La Jolla, CA 92037.
Proc Natl Acad Sci U S A. 1990 Jul;87(14):5359-62. doi: 10.1073/pnas.87.14.5359.
The size of synaptic quanta has been found to display considerable variation in cultured hippocampal neurons, but the source of this variability was previously unknown. We have now compared the properties of locally evoked miniature excitatory postsynaptic currents in cultured hippocampal neurons and in thin hippocampal slices using whole-cell patch-clamp recordings. The variability in miniature excitatory postsynaptic current size was similar in both preparations and occurred in cultured neurons when only one or a few synaptic boutons were stimulated. Thus, the variability in miniature excitatory postsynaptic current amplitude is not an artifact of cultured neurons and arises predominantly from variability within a single bouton. Possible origins of this variability are discussed.
人们发现，培养的海马神经元中突触量子的大小存在显著差异，但此前这种变异性的来源尚不清楚。我们现在使用全细胞膜片钳记录技术，比较了培养的海马神经元和薄海马切片中局部诱发的微小兴奋性突触后电流的特性。在两种标本中，微小兴奋性突触后电流大小的变异性相似，并且在仅刺激一个或几个突触小体时，培养的神经元中也会出现这种变异性。因此，微小兴奋性突触后电流幅度的变异性不是培养神经元的假象，并且主要源于单个突触小体内的变异性。文中讨论了这种变异性可能的来源。
