心肺压力感受器持续卸荷对前臂血流、血管阻力及心率变异性谱的影响

低压值下体负压（ＬＢＮＰ）可仅使心肺压力感受器卸荷。采用－２ｋＰａＬＢＮＰ实验结果表明：ＬＢＮＰ既不引起动脉血压变化,也不引起心率改变,但却引起基础胸阻抗（Ｚ。）从对照的２１．８±０．４升高到２２．５±０．５Ω（Ｐ＜０．０１）,前臂血管阻力（ＦＶＲ）从１２．３±０．９升高到１９．９±１．４Ｕ（Ｐ＜０．０１）,前臂血流（ＦＢＦ）从对照时７．１±０．５降低到４．３±０．３ｍｌ·ｍｉｎ￣（－１）·１００ｍｌ￣（－１）,心率变异性谱（ＨＲＶ）未发生任何变化,即心肺压力感受器卸荷时心脏自主神经活动水平与均衡性不受影响。由于ＦＶＲ和ＦＢＦ的变化可间接反映外周血管交感传出活动水平,上述实验结果提示,心肺压力感受器对外周血管及心脏自主神经活动的调节可能存在机能分化现象。     

微循环研究常用部位的肽能和胺能神经支配

以逆行追踪与免疫细胞化学相结合法,探讨了大鼠提睾肌、盲肠系膜和耳廓等微循环研究常用部位的神经肽Ｙ（ＮＰＹ）、降钙素基因相关肽（ＣＧＲＰ）、甲啡吠（Ｍ－ＥＮＤ）和５－羟色胺（５－ＨＴ）等肽能和胺能神经的支配。结果表明：支配提睾肌的运动和感觉神经元分别含有５－ＨＴ和ＣＧＲＰ。支配提睾肌血管、盲肠系膜及其血管的交感神经元,一部分含有ＮＰＹ,一部分含有Ｍ－ＥＮＫ;支配耳廓局部的运动和感觉神经元均含有ＣＧＲ     

损毁和刺激垂体对大鼠痛阈的影响

采用局限性损毁和刺激垂体的方法,以行为测痛为指标,观察大鼠垂体在痛觉调节中的作用以及地塞米松（Ｄｅｘ）对其影响。实验结果显示,损毁垂体中间叶（ＩＬ）及邻近的前叶（ＡＬ）,大鼠痛阈明显低于手术前的痛阈（Ｐ＜０．０１）。电刺激垂体的上述同样部位,大鼠痛阈明显高于手术基础值及自身假刺激值（Ｐ＜０．００１）。经Ｄｅｘ处理的动物,电刺激垂体不再引起痛阈升高。结果表明,大鼠垂体ＩＬ及靠近ＡＬ与痛调节有关,这种     

荧光探针在大鼠胃粘膜表面疏水性研究中的应用

采用１－萘胺－８－磺酸（ＡＮＳ）为疏水探针,对大鼠胃粘膜表面疏水性作了研究,结果表明：以ＡＮＳ（２５μｍｏｌ／Ｌ）与胃粘膜表面刮取物（胃粘液凝胶层）混合后的萤光强度（正常为１．２３±０．１９ＲＦＵ／胃）可代表该粘液层的疏水性;以不同浓度ＡＮＳ与胃粘液混合后的萤光强度呈饱和趋势,可用Ｓｃａｔｃｈａｒｄ作图法求得粘液中ＡＮＳ的最大萤光强度（２．４６７±０．６３８ＲＦＵ／胃）和相对亲和系数（０．０３２±０．０１６）,它们可分别代表胃粘液中疏水基团的总量和单个基团的疏水性,从而可阐明胃粘膜被盐酸损伤后凝胶层粘液的ＡＮＳ萤光减弱,系其疏水基团总量减少,而非单个基团的疏水性改变所致。     

西藏林芝真蚋亚属三新种（双翅目：蚋科）

本文记述西藏林芝真蚋亚属Ｅｕｓｉｍｕｌｉｕｍ三种：凸端真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｃｏｎｃａｖｕｓｔｙｌｕｍｓｐ．ｎｏｖ．、林芝真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｌｉｎｇｚｉｅｎｓｅｓｐ．ｎｏｖ．、裂缘真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｓｃｈｉｚｏｌｏｍｕｎｓｐ．ｎｏｖ 。     

Wiener analysis of spike transmission by identified molluscan neurons

A mathematical model of spike train transmission by identified molluscan neurons was obtained by Wiener analysis. Poisson-distributed sequences of near-threshold stimuli were used as input trains for model construction and testing. Assuming that the error of describing responses of the synapse-neuron system purely by mean outflow frequency is 100%, addition of a linear component to the equation of the model reduces this error to 25%, and addition of a term allowing for nonlinear properties of the system reduces it to 16%. Comparison of the standard error of predicted responses of the model to testing stimulus trains and of responses of a real neuron to these same trains showed that the prediction error with allowance for nonlinear properties does not exceed 21%. Choice of adequate criteria for comparing model and experimental results is discussed.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 16, No. 1, pp. 49–54, January–February, 1984.     

Conducting pathways of the rabbit lumbar sympathetic ganglia

Conducting pathways of ganglia from the lumbar portion (L₃–L₅) of the sympathetic trunk in rabbits were studied by recording action potentials from nerves of the ganglia evoked by stimulation of other nerves of these ganglia, and by intracellular recording from single neurons. Besides the well-known system of descending preganglionic fibers, which enter the trunk through white rami communicantes and, as they pass through the ganglia, form synapses on ganglionic neurons, some preganglionic fibers were shown to enter the sympathetic chain through gray rami communicantes and to run in both ascending and descending directions, forming synaptic connections with neurons of the lumbar ganglia.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 16, No. 2, pp. 247–254, March–April, 1984.     

Preference of a revolving target to a stationary one by the big brown bat, Eptesicus fuscus

Utilizing a three-ramp platform, we studied the detection of a revolving and a stationary target in the presence of background clutter by trained Eptesicus fuscus. During the test, the mean amplitude of echo from either target was always larger than that of the background echoes at the bat-to-target distance of 30, 70 and 100 cm. The amplitude of the echo reflected back from a revolving target was modulated between a maximum and a minimum value. An electric motor was used to revolve a target. The frequency contents of the motor noise were mostly below 1 kHz. While the total percent response of approaching either target is always more than 90% at every bat-to-target distance tested, the bats approach a revolving target more frequently than a stationary one. Echolocation pulses emitted by the bats during the test were recorded and analyzed. The bats shortened their pulse durations and interpulse intervals and lowered the frequency contents as they entered into the crawling phase from the searching phase. Potential interference of background echoes and ambient noise with the performance of the bats is discussed. The preference of a revolving target to a stationary one by the bats is perhaps due to the fact that a revolving target has a higher releasing value than a stationary one does.