Koepke J P, Light K C, Obrist P A, Morris M
Am J Physiol. 1984 Aug;247(2 Pt 2):F213-8. doi: 10.1152/ajprenal.1984.247.2.F213.
Behavioral stress increases arterial pressure while decreasing urine flow rate; the urine flow rate response can be abolished by surgical renal denervation. In this study, the effects of infusion of alpha-adrenoceptor antagonists (intravenous phenoxybenzamine or prazosin) on the antidiuretic and plasma vasopressin responses to stress were examined. Without alpha-adrenoceptor blockade, 20 min of stress increased arterial pressure and decreased urine flow rate, but no change in urine osmolality or plasma vasopressin concentration occurred. Arterial pressure and urine flow rate returned to base-line level during a 20-min recovery period. With alpha-adrenoceptor blockade, which prevented the arterial pressure response to stress, urine flow rate still decreased during stress, but urine osmolality and plasma vasopressin concentration increased. The decrease in urine flow rate and increase in urine osmolality and plasma vasopressin concentration persisted into the first 20-min recovery period but returned to base-line level during a second 20-min recovery period. We conclude that the antidiuretic response to behavioral stress in conscious dogs with saline infusion alone is not mediated via a change in vasopressin release. In contrast, the antidiuretic response to behavioral stress with alpha-adrenoceptor antagonist infusion may be mediated via an increased release of vasopressin.
行为应激会使动脉血压升高，同时降低尿流率；尿流率反应可通过手术切除肾神经来消除。在本研究中，研究了输注α-肾上腺素能受体拮抗剂（静脉注射酚苄明或哌唑嗪）对应激性抗利尿和血浆血管加压素反应的影响。在没有α-肾上腺素能受体阻断的情况下，20分钟的应激会使动脉血压升高，尿流率降低，但尿渗透压或血浆血管加压素浓度没有变化。在20分钟的恢复期内，动脉血压和尿流率恢复到基线水平。在α-肾上腺素能受体阻断的情况下，这阻止了动脉血压对应激的反应，应激期间尿流率仍会降低，但尿渗透压和血浆血管加压素浓度会升高。尿流率的降低以及尿渗透压和血浆血管加压素浓度的升高持续到第一个20分钟的恢复期，但在第二个20分钟的恢复期内恢复到基线水平。我们得出结论，仅输注生理盐水的清醒犬对行为应激的抗利尿反应不是通过血管加压素释放的变化介导的。相比之下，输注α-肾上腺素能受体拮抗剂时对行为应激的抗利尿反应可能是通过血管加压素释放增加介导的。
