Samson W K, Aguila M C, Martinovic J, Antunes-Rodrigues J, Norris M
Department of Physiology, University of Texas Health Science Center at Dallas 75235-9040.
Peptides. 1987 May-Jun;8(3):449-54. doi: 10.1016/0196-9781(87)90008-8.
The ability of synthetic atrial natriuretic factor (ANF) to inhibit vasopressin (AVP) release, as well as its action to inhibit water intake and salt preference in the rat, suggest a role for the peptide in the hypothalamic control of fluid volume in addition to its established actions in the kidney. We report here evidence for a direct, hypothalamic site of action of ANF to inhibit, specifically, AVP secretion. Third cerebroventricular infusion of 1.0 (p less than 0.05) and 2.0 (p less than 0.025) nmoles ANF significantly inhibited AVP release in euvolemic, normally hydrated rats while IV doses of ANF failed to significantly alter AVP release except when 5 nmoles (p less than 0.05) were infused. No significant effects on oxytocin (OT) release were observed. Vasopressin release from median eminence or pituitary, neural lobe explants during static, in vitro incubations was not significantly altered by doses of ANF ranging from 10(-12) to 10(-7) molar. Release of AVP during perifusion of neural lobe explants in the presence of ANF was similarly unaffected. However, AVP and not OT release from hypothalamo-neurohypophysial system explants was significantly inhibited in the presence of 10(-8) and 10(-7) M ANF, suggesting an action of the peptide at the levels of the AVP-producing cell bodies in the included supraoptic nucleus either directly or via an action on an interneuron, and not at the AVP-containing terminal fields in the median eminence or neural lobe.
合成心房钠尿肽（ANF）抑制血管加压素（AVP）释放的能力，以及其在大鼠中抑制水摄入和盐偏好的作用，表明该肽除了在肾脏中已确定的作用外，在体液容量的下丘脑控制中也发挥作用。我们在此报告证据，表明ANF在下丘脑有直接作用位点，可特异性抑制AVP分泌。向第三脑室注入1.0纳摩尔（p<0.05）和2.0纳摩尔（p<0.025）的ANF，可显著抑制血容量正常、水合状态正常的大鼠的AVP释放，而静脉注射ANF剂量除5纳摩尔（p<0.05）外，均未显著改变AVP释放。未观察到对催产素（OT）释放有显著影响。在静态体外培养期间，中隆或垂体神经叶外植体释放的血管加压素，在10^(-12)至10^(-7)摩尔范围内的ANF剂量下未显著改变。在存在ANF的情况下，神经叶外植体灌流期间AVP的释放同样未受影响。然而，在存在10^(-8)和10^(-7) M ANF的情况下，下丘脑 - 神经垂体系统外植体释放的AVP而非OT显著受到抑制，这表明该肽在包含的视上核中产生AVP的细胞体水平上有直接作用，或通过对中间神经元的作用，而不是在中隆或神经叶中含AVP的终末区域发挥作用。
