摘要
应用在体微电极胞内电位记录技术分别向猫扣带回前部躯体伤害性感受神经元与非伤害性感受神经元内注入波宽50ms、不同强度(-5 n A^+5 n A)的系列超级化或去极化电流,记录神经元的膜电学反应,计算膜电学参数。通过对比躯体伤害性与非伤害性感受神经元的膜电学特性,从该侧面为深入了解该脑区躯体伤害性感受的特性及机制提供实验依据。在57只猫扣带回前部共记录了188个神经元,其中172个为躯体伤害性感受神经元(91.5%),另外16个为躯体非伤害性感受神经元(8.5%)。结果表明:躯体伤害性与非伤害性感受神经元的注入电流(I)-膜电位(V)曲线都为"S"型;注入电流强度的绝对值≤1n A时,躯体伤害性与非伤害性感受神经元I-V曲线的I与V均呈线性相关(r都为0.99);而注入电流强度的绝对值>1 n A时,两者均呈现内向或外向整流作用;但是,与躯体非伤害性感受神经元相比,躯体伤害性感受神经元的整流作用较大,对刺激的适应性较低,诱发放电的频率较高(P<0.01),并且,随注入的去极化电流强度的逐渐增大,放电频率变化也较大;另外,躯体伤害性感受神经元的膜电阻、膜电容、时间常数也明显大于躯体非伤害性感受神经元(P<0.05或P<0.01)。这些结果提示扣带回前部躯体伤害性与非伤害性感受神经元在直径大小、细胞膜结构等方面存在差异。
Using intracellular potential recording technique in vivo, a series of hyperpolarizing and depolarizing currents at different intensities with a 50-ms duration were injected to somatic nociceptive neurons （SNNs） and somatic non-nociceptive neurons （SNNNs） in the anterior cingulate gyrus （ACG） of cats. The membrane electrical responses of the neurons were recorded, and the membrane electrical parameters of the neurons were calculated for comparative study on membrane electrical properties of SNNs and SNNNs of the ACG. A total of 188 ACG neurons from 57 cats were recorded. Among the 188 neurons, 172 （91.5%） and 16 （8.5%） were SNNs and SNNNs, respectively. The I-V curves of SNNs and SNNNs in the ACG were ＂S＂ shapes. When the absolute value of injected current intensity was less than or equal to 1 nA （〈 1 nA）, the I and V of I-V curves of both SNNs and SNNNs were linearly correlated （rSNNs= 0.99, RSNNNs = 0.99）. When the absolute value of injected current intensity was more than 1 hA, both SNNs and SNNNs showed a certain inward or outward rectification behavior. Compared with SNNNs, SNNs had stronger rectification and lower adaptability （P 〈 0.01）. With the increase of injected current intensity, the changes of frequency of discharges of SNNs were higher than those of SNNNs. In addition, the membrane resistance （Rm）, the membrane capacity （Cm） and the time constant （τ） of SNNs were larger than those of SNNNs （P 〈 0.05 or P 〈 0.01）. The differences in the membrane electrical properties between SNNs and SNNNs in the ACG suggested the disparity in neuronal cell size and cell membrane structure between them. The results of this study provided the experimental basis for deeply elucidating the mechanisms of somatic nociceptive sensation and characteristics on the membrane electrical aspects of ACG neurons.
出处
《生理学报》
CAS
CSCD
北大核心
2015年第2期181-185,共5页
Acta Physiologica Sinica
基金
supported by the Science and Technology Project of Education Department of Liaoning Province
China(No.L2012376)
the Scientific Research Foundation for the Returned Overseas Chinese Scholars
Ministry of Education
China(No.2008101)
the Scientific Foundation of Science and Technology Department
Shenyang City
China(No.F10-205-1-42)
关键词
膜电学特性
扣带回前部
伤害性感受神经元
membrane electrical property
anterior cingulate gyrus
nociceptive neuron
