Wood C E, Rudolph A M
Am J Physiol. 1983 Jun;244(6):E555-9. doi: 10.1152/ajpendo.1983.244.6.E555.
To test the hypothesis that changes in carotid vascular pressure influence ovine ACTH and corticosteroid secretion, we subjected 6- to 7-wk-old conscious lambs to bilateral carotid occlusion with or without prior vagosympathetic blockade. Reversible vagosympathetic blockade, produced by injection of 2% lidocaine onto the vagosympathetic trunks, inhibited the reflex changes in heart rate after intravenous injection of phenylephrine or during carotid occlusion. Vagosympathetic blockade by itself did not alter arterial pressure or heart rate but did increase circulating levels of ACTH and corticosteroids. This suggests that afferent fibers in the vagosympathetic trunks tonically inhibit the secretion of ACTH. Bilateral carotid occlusion did not change plasma ACTH or corticosteroid concentrations. Bilateral carotid occlusion plus prior vagosympathetic blockade stimulated increases in plasma ACTH and corticosteroid concentrations that were larger than responses to vagosympathetic blockade alone. The results demonstrate that changes in carotid vascular pressure influence ovine ACTH and corticosteroid secretion only during vagosympathetic blockade and therefore suggest that carotid vascular mechanoreceptors interact with other mechanoreceptors having vagosympathetic afferent fibers.
为了验证颈动脉血管压力变化会影响绵羊促肾上腺皮质激素（ACTH）和皮质类固醇分泌这一假设，我们对6至7周龄的清醒羔羊进行双侧颈动脉闭塞处理，有无预先进行迷走交感神经阻滞。通过向迷走交感神经干注射2%利多卡因产生可逆性迷走交感神经阻滞，抑制了静脉注射去氧肾上腺素后或颈动脉闭塞期间心率的反射性变化。迷走交感神经阻滞本身并未改变动脉血压或心率，但确实增加了ACTH和皮质类固醇的循环水平。这表明迷走交感神经干中的传入纤维可紧张性抑制ACTH的分泌。双侧颈动脉闭塞并未改变血浆ACTH或皮质类固醇浓度。双侧颈动脉闭塞加预先迷走交感神经阻滞刺激血浆ACTH和皮质类固醇浓度升高，且升高幅度大于单独迷走交感神经阻滞的反应。结果表明，颈动脉血管压力变化仅在迷走交感神经阻滞期间影响绵羊ACTH和皮质类固醇分泌，因此提示颈动脉血管机械感受器与具有迷走交感神经传入纤维的其他机械感受器相互作用。
