Activation of histamine H-1 receptors in the nucleus tractus solitarii attenuates cardiac baroreceptor reflex function in rats

作者：Takagishi M; Gouraud S S; Bhuiyan M E R; Kohsaka A; Maeda M; Waki H^*

来源：Acta Physiologica, 2014, 211(1): 73-81.

DOI：10.1111/apha.12278

• baroreceptor reflex
• histamine
• nucleus tractus solitarii

AimThe nucleus tractus solitarii (NTS) is a central brainstem structure that plays an important role in regulating cardiovascular homeostasis. In this study, we examined whether H-1 receptors in the NTS can control the baroreceptor reflex function by modulating synaptic transmission.
MethodsCardiac baroreceptor reflex function was assessed before and after the microinjection of 2-pyridylethylamine (10-25nmol), a histamine H-1 receptor-specific agonist, into the NTS of urethane-anaesthetized Wistar rats. The cardiovascular responses induced by l-glutamate microinjection into the NTS were also examined before and after the NTS administration of 2-pyridylethylamine.
ResultsNucleus tractus solitarii microinjections of 2-pyridylethylamine significantly inhibited the gain of the cardiac baroreceptor reflex and bradycardiac/depressor responses induced by l-glutamate microinjection into the NTS. These findings suggest that histamine H-1 receptors regulate the cardiac baroreceptor reflex in a post-synaptic manner to inhibit barosensitive NTS neurons.
ConclusionTaken together with our previous findings, the present results provide further evidence that histamine may play a role within the NTS in regulating cardiovascular homeostasis.

• 出版日期2014-5