Oliveira Leandro A, Almeida Jeferson, Gomes-de-Souza Lucas, Benini Ricardo, Crestani Carlos C
Laboratory of Pharmacology, Department of Natural Active Principles and Toxicology, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Rodovia Araraquara-Jau Km 01 (Campus Universitário), 14800-903, Araraquara, SP, Brazil.
Joint UFSCar-UNESP Graduate Program in Physiological Sciences, PIPGCF, São Carlos, SP, Brazil.
Eur J Neurosci. 2017 Jul;46(2):1805-1812. doi: 10.1111/ejn.13622. Epub 2017 Jul 3.
The baroreflex is an important blood pressure regulating mechanism. The bed nucleus of stria terminalis (BNST) modulates the baroreflex function. However, the local BNST neurochemical mechanisms involved in control of baroreflex responses are not completely understood. Therefore, in this study, we investigated the involvement of corticotropin-releasing factor (CRF) receptors within the BNST in baroreflex control of heart rate in unanesthetized rats. For this, we evaluated effects of bilateral microinjection into the BNST of either the selective CRF receptor antagonist CP376395 (5 nmol/100 nL) or the selective CRF receptor antagonist antisauvagine-30 (5 nmol/100 nL) in bradycardiac response evoked by blood pressure increases caused by intravenous infusion of phenylephrine as well as tachycardiac response to blood pressure decrease caused by intravenous infusion of sodium nitroprusside. Bilateral microinjection of CP376395 into the BNST decreased the baroreflex bradycardiac response without affecting the reflex tachycardia. Conversely, BNST treatment with antisauvagine-30 decreased heart rate response during blood pressure drop without affecting the reflex bradycardia. Overall, these findings provide evidence of an involvement of CRF neurotransmission within the BNST in baroreflex activity. Nevertheless, data indicate that local CRF and CRF receptors differently modulate the baroreflex control of heart rate.
压力反射是一种重要的血压调节机制。终纹床核（BNST）调节压力反射功能。然而，参与压力反射反应控制的局部BNST神经化学机制尚未完全明确。因此，在本研究中，我们调查了BNST内促肾上腺皮质激素释放因子（CRF）受体在未麻醉大鼠心率压力反射控制中的作用。为此，我们评估了向BNST双侧微量注射选择性CRF受体拮抗剂CP376395（5 nmol/100 nL）或选择性CRF受体拮抗剂抗 sauvagine-30（5 nmol/100 nL）对静脉注射去氧肾上腺素引起的血压升高所诱发的心动过缓反应以及静脉注射硝普钠引起的血压降低所诱发的心动过速反应的影响。向BNST双侧微量注射CP376395可降低压力反射性心动过缓反应，而不影响反射性心动过速。相反，用抗sauvagine-30处理BNST可降低血压下降期间的心率反应，而不影响反射性心动过缓。总体而言，这些发现提供了证据表明BNST内的CRF神经传递参与了压力反射活动。然而，数据表明局部CRF和CRF受体对心率压力反射控制的调节方式不同。
