Blockade of the dorsomedial hypothalamus and the perifornical area inhibits respiratory responses to arousing and stressful stimuli
Blockade of the dorsomedial hypothalamus and the perifornical area inhibits respiratory responses to arousing and stressful stimuli
复制标题
DOI：
10.1152/ajpregu.00415.2014
复制
发表时间：
2015-05-15
影响因子：
2.8
通讯作者：
Nalivaiko, Eugene
中科院分区：
文献类型：
--
作者：
Bondarenko, Evgeny;Beig, Mirza I.;Nalivaiko, Eugene
下丘脑背内侧区（DMH）和穹窿周围区（DMH/PeF）是中枢自主神经处理的关键区域之一。以前的研究已经确定，这个区域包含可能参与呼吸处理的神经元;然而，这从未在有意识的动物中进行过测试。我们的研究的目的是调查DMH/PeF区参与介导的呼吸反应，各种强度和持续时间的压力。成年雄性Wistar大鼠（n = 8）接受GABA（A）激动剂蝇蕈醇或生理盐水双侧微量注射到DMH/PeF中，并使用全身体积描记法进行呼吸记录。呈现声刺激（500 ms白色噪声）诱发呼吸频率的瞬态响应，与刺激强度成比例，范围为+44 +/- 27至+329 +/- 31个周期/分钟（cpm）。阻断DMH/PeF几乎完全消除了对40- 70-dB刺激的呼吸频率和潮气量反应，并显著减弱了对80- 90-dB刺激的反应。此外，在适应期（新的环境应激），它显着减弱呼吸频率。光刺激（30秒，2,000勒克斯）以及15分钟的束缚应激分别使呼吸频率从95 +/- 4.0增加到236 +/- 29 cpm和从117 +/- 5.2增加到189 +/- 13 cpm; DMH/PeF阻断后，这种反应消失。我们的结论是DMH/PeF区的完整性是必不可少的压力和报警刺激的呼吸反应的产生。
The dorsomedial hypothalamus (DMH) and the perifornical area (DMH/PeF) is one of the key regions of central autonomic processing. Previous studies have established that this region contains neurons that may be involved in respiratory processing; however, this has never been tested in conscious animals. The aim of our study was to investigate the involvement of the DMH/PeF area in mediating respiratory responses to stressors of various intensities and duration. Adult male Wistar rats (n = 8) received microinjections of GABA(A) agonist muscimol or saline into the DMH/PeF bilaterally and were subjected to a respiratory recording using whole body plethysmography. Presentation of acoustic stimuli (500-ms white noise) evoked transient responses in respiratory rate, proportional to the stimulus intensity, ranging from +44 +/- 27 to +329 +/- 31 cycles/min (cpm). Blockade of the DMH/PeF almost completely abolished respiratory rate and tidal volume responses to the 40- to 70-dB stimuli and also significantly attenuated responses to the 80- to 90-dB stimuli. Also, it significantly attenuated respiratory rate during the acclimatization period (novel environment stress). The light stimulus (30-s 2,000 lux) as well as 15-min restraint stress significantly elevated respiratory rate from 95 +/- 4.0 to 236 +/- 29 cpm and from 117 +/- 5.2 to 189 +/- 13 cpm, respectively; this response was abolished after the DMH/PeF blockade. We conclude that integrity of the DMH/PeF area is essential for generation of respiratory responses to both stressful and alerting stimuli.