前列腺素E2对大鼠视前区和下丘脑腹内侧区温度敏感神经元的影响。

Effect of prostaglandin E2 on thermoresponsive neurones in the preoptic and ventromedial hypothalamic regions of rats.

作者信息

Morimoto A, Murakami N, Watanabe T

机构信息

Department of Physiology, Yamaguchi University School of Medicine, Japan.

出版信息

J Physiol. 1988 Nov;405:713-25. doi: 10.1113/jphysiol.1988.sp017357.

DOI:10.1113/jphysiol.1988.sp017357

PMID:3255803

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC1191000/

Abstract

We investigated the effect of microinjection of prostaglandin E2 (PGE2) into the preoptic (POA) or the ventromedial hypothalamic (VMH) region on rectal temperature in rats. Fever was induced by microinjection of PGE2 into the POA or the VMH regions. The febrile responses induced by PGE2 injected into the VMH region were significantly greater than those induced by injection into the POA region. 2. The effect of temperature on neuronal activity in the POA and the VMH regions was investigated by using slice preparations from rats. It was revealed that there exist many thermoresponsive neurones in the VMH region as well as in the POA region, and that the proportion of thermoresponsive neurones out of the total neurones examined in the VMH region was almost identical to that in the POA region. In addition, the warm-responsive neurones in the VMH region exhibited larger thermal coefficients than those in the POA region. 3. When PGE2 was applied in a recording chamber where the tissue slice was perfused, most of the neurones in the VMH region which responded to PGE2 showed a decrease in their firing rate, while those in the POA region showed an increase in their firing rate, regardless of their thermoresponsiveness. In the POA region, PGE2 began to affect the activities of the warm-responsive neurones in the range of 5 x 10(-7) to 7 x 10(-6) M, whereas maximum responses were obtained between the concentrations of 5 x 10(-6) and 5 x 10(-5) M. In the VMH region, PGE2 began to change the activities of the warm-responsive neurones in the range of 5 x 10(-8) to 5 x 10(-7) M, and the maximum effect of PGE2 on the VMH warm-responsive neurones occurred between the concentrations of 8 x 10(-7) and 4 x 10(-5) M. 4. The present results show that neurones exhibit different responsiveness to PGE2 and different sensitivity to PGE2 between the POA and the VMH regions. Nevertheless, microinjection of PGE2 into either the POA or the VMH region produces fever. Therefore, it is suggested that fever is produced by complex neuronal networks in the central nervous system.

摘要

我们研究了向大鼠视前区（POA）或下丘脑腹内侧区（VMH）微量注射前列腺素E2（PGE2）对直肠温度的影响。通过向POA或VMH区域微量注射PGE2诱导发热。向VMH区域注射PGE2所诱导的发热反应明显大于向POA区域注射所诱导的发热反应。2. 利用大鼠脑片标本研究了温度对POA和VMH区域神经元活动的影响。结果显示，VMH区域和POA区域均存在许多温度敏感神经元，且VMH区域中温度敏感神经元占所检测神经元总数的比例与POA区域几乎相同。此外，VMH区域的温敏神经元比POA区域的温敏神经元表现出更大的热系数。3. 当在灌注组织切片的记录室中应用PGE2时，VMH区域中大多数对PGE2有反应的神经元放电频率降低，而POA区域的神经元放电频率增加，无论其温度敏感性如何。在POA区域，PGE2在5×10⁻⁷至7×10⁻⁶ M范围内开始影响温敏神经元的活动，而在5×10⁻⁶至5×10⁻⁵ M浓度之间获得最大反应。在VMH区域，PGE2在5×10⁻⁸至5×10⁻⁷ M范围内开始改变温敏神经元的活动，PGE2对VMH温敏神经元的最大作用出现在8×10⁻⁷至4×10⁻⁵ M浓度之间。4. 目前的结果表明，POA区域和VMH区域的神经元对PGE2表现出不同反应性和不同敏感性。然而，向POA或VMH区域微量注射PGE2均会引起发热。因此，提示发热是由中枢神经系统中的复杂神经网络产生的。