Luheshi G N, Bluthé R M, Rushforth D, Mulcahy N, Konsman J P, Goldbach M, Dantzer R
School of Biological Sciences, University of Manchester, UK.
Auton Neurosci. 2000 Dec 20;85(1-3):127-32. doi: 10.1016/S1566-0702(00)00231-9.
Vagal afferent signals, have been implicated in cytokine mediated interactions between the periphery and the central nervous system. Studies in experimental animals have shown that cytokine induced activation of brain mediated responses to infection such as fever, sickness behaviour and pituitary-adrenal activation, are inhibited by subdiaphragmatic vagotomy. We have previously proposed that the peripheral signal to the brain in fever is of a humoral nature while others have suggested that either neural afferents or a mixture of both humoral and neural signals may be involved. The objective of the present study was to examine further the role of vagal transmission, in mediating the febrile response to a systemic injection of IL-1beta in rats and to compare this with changes in social exploration behaviour. Intraperitoneal injection of IL-1beta (1.0-30.0 microg/kg) inhibited social exploration in rats and this was attenuated in vagotomized animals. Injection of increasing concentrations of IL-1beta (0.1-1.0 microg/rat) induced significant (P<0.001) increases in core body temperature. However, in contrast to effects on social exploration, the increase in temperature was not inhibited by vagotomy at any of the doses used. These observations demonstrate a dissociation between the two brain mediated events, one of which is dependent on the integrity of the vagus nerve (social exploration) while the other (fever) is apparently generated by different mechanisms which may include circulating pyrogens.
迷走神经传入信号已被认为参与了细胞因子介导的外周与中枢神经系统之间的相互作用。对实验动物的研究表明，细胞因子诱导的大脑介导的对感染的反应，如发热、疾病行为和垂体-肾上腺激活，可被膈下迷走神经切断术所抑制。我们之前曾提出，发热时向大脑传递的外周信号具有体液性质，而其他人则认为可能涉及神经传入或体液和神经信号的混合。本研究的目的是进一步研究迷走神经传递在介导大鼠全身注射白细胞介素-1β后的发热反应中的作用，并将其与社会探索行为的变化进行比较。腹腔注射白细胞介素-1β（1.0 - 30.0微克/千克）可抑制大鼠的社会探索行为，而在迷走神经切断的动物中这种抑制作用减弱。注射浓度不断增加的白细胞介素-1β（0.1 - 1.0微克/只大鼠）可使核心体温显著升高（P<0.001）。然而，与对社会探索行为的影响不同，在所使用的任何剂量下，迷走神经切断术均未抑制体温升高。这些观察结果表明这两种大脑介导的事件之间存在分离，其中之一依赖于迷走神经的完整性（社会探索行为），而另一个（发热）显然是由不同机制产生的，这些机制可能包括循环中的致热原。
