Jones D G, Devon R M
Brain Res. 1978 May 19;147(1):47-63. doi: 10.1016/0006-8993(78)90771-0.
A series of adult male rats was analyzed to test the effects of varying doses of pentobarbitone sodium on the ultrastructure of synapses in the molecular layer of the parietal cortex. The rats were divided into the following categories: unanaesthetized stunned, unanaesthetized cannulated and those subjected to 40, 80, 160, 300, or 400 mg/kg pentobarbitone. All material was examined both qualitatively and quantitatively after aldehyde-OsO4 or ethanolic phosphotungstic acid (E-PTA) treatment. The principal qualitative observations were: the preponderance in the unanaesthetized stunned and 160-400 mg/kg material of a variety of intraterminal profiles including synaptic vesicles, mitochondria, coated vesicles, tubular profiles, vacuoles, cisterns and double membrane profiles; the presence of exocytotic sites along the presynaptic membrane in the unanaesthetized stunned and cannulated material; the presence of endocytotic sites over the limiting membrane of the terminal away from the cleft in the unanaesthetized stunned and 160-400 mg/kg material; the prominence of the presynaptic network in the unanaesthetized and 40 mg/kg E-PTA material; discontinuity of the cleft material in the 40-160 mg/kg material. Findings to emerge from the quantitative aspect of the study show that pentobarbitone influences synaptic curvature, with a marked increase in curvature negativity over the 0-80 mg/kg dose range and a decrease in negativity at higher dose levels. The increase in curvature negativity is accompanied by an increase in synaptic length and dense projection numbers, with a consonant increase in the perimeter and area of the presynaptic terminal. Reversal of the negativity trend at higher dose levels is parallelled by reversal of these accompanying trends. Both sets of findings can be accounted for by membrane recycling within the terminal, supporting a membrane redistribution hypothesis.
对一系列成年雄性大鼠进行分析，以测试不同剂量的戊巴比妥钠对顶叶皮质分子层突触超微结构的影响。大鼠被分为以下几组：未麻醉致昏组、未麻醉插管组以及接受40、80、160、300或400mg/kg戊巴比妥钠处理的组。所有材料在经过醛-锇酸或乙醇磷钨酸（E-PTA）处理后进行定性和定量检查。主要的定性观察结果如下：在未麻醉致昏组和160 - 400mg/kg剂量组的材料中，各种终末内结构占优势，包括突触小泡、线粒体、被膜小泡、管状结构、液泡、池和双膜结构；在未麻醉致昏组和插管组的材料中，突触前膜沿线存在胞吐位点；在未麻醉致昏组和160 - 400mg/kg剂量组的材料中，终末远离裂隙的限制膜上存在胞吞位点；在未麻醉组和40mg/kg E-PTA处理的材料中，突触前网络突出；在40 - 160mg/kg剂量组的材料中，裂隙物质不连续。该研究定量方面的结果表明，戊巴比妥会影响突触曲率，在0 - 80mg/kg剂量范围内曲率负值显著增加，而在更高剂量水平时负值降低。曲率负值的增加伴随着突触长度和致密突起数量的增加，突触前终末的周长和面积也相应增加。在更高剂量水平时负值趋势的逆转与这些伴随趋势的逆转平行。两组结果都可以通过终末内的膜循环来解释，支持膜重新分布假说。
