Saravia Flavia E, Pietranera Luciana, Lima Analia, Roig Paulina, Revsin Yanina, De Nicola Alejandro F
Laboratory of Neuroendocrine Biochemistry, Instituto de Biologi;a y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina.
Neurosci Lett. 2002 Sep 6;329(3):344-8. doi: 10.1016/s0304-3940(02)00666-3.
Mineralocorticoids (MC) play an important role in development of salt appetite. Part of this effect involves the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei, in which MC treatment increases arginine vasopressin (AVP) synthesis and release. Since the AVP system is also modulated by nitric oxide (NO), we studied if deoxycorticosterone acetate (DOCA) treatment changed the number of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) active neurons and neuronal NO synthase (nNOS)-immunoreactive (IR) cells in the PVN and SON. After four injections of DOCA (10 mg/rat per day), rats developed a salt appetite and increased NADPH-d active and nNOS-IR neurons in both nuclei. A single DOCA injection did not change salt consumption or nNOS-IR cells, but increased the number of NADPH-d positive neurons in the PVN only. Therefore, while acute MC treatment stimulated the activity of pre-existing enzyme, chronic steroid treatment recruited additional neurons showing nNOS immunoreactivity/NADPH-d activity. These data suggest a role for NO produced in the PVN and SON in DOCA stimulatory effects on AVP mRNA and salt appetite.
盐皮质激素（MC）在盐食欲的形成中起重要作用。这种作用的一部分涉及下丘脑室旁核（PVN）和视上核（SON），在这些核中，MC处理会增加精氨酸加压素（AVP）的合成与释放。由于AVP系统也受一氧化氮（NO）调节，我们研究了醋酸脱氧皮质酮（DOCA）处理是否会改变PVN和SON中烟酰胺腺嘌呤二核苷酸磷酸黄递酶（NADPH-d）活性神经元和神经元型一氧化氮合酶（nNOS）免疫反应性（IR）细胞的数量。在注射四次DOCA（每天10 mg/只大鼠）后，大鼠出现了盐食欲，并且两个核中的NADPH-d活性神经元和nNOS-IR神经元数量增加。单次注射DOCA不会改变盐摄入量或nNOS-IR细胞，但仅增加PVN中NADPH-d阳性神经元的数量。因此，虽然急性MC处理刺激了已存在酶的活性，但慢性类固醇处理会使更多显示nNOS免疫反应性/NADPH-d活性的神经元被募集。这些数据表明，PVN和SON中产生的NO在DOCA对AVP mRNA和盐食欲的刺激作用中发挥作用。
