Laboratory of Behavioral Neuroendocrinology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.
Neuroscience. 2010 Oct 27;170(3):773-81. doi: 10.1016/j.neuroscience.2010.07.051. Epub 2010 Aug 3.
Stress is one of the important factors to activate the sympathetic nervous system. We recently reported that central administration of corticotropin-releasing factor (CRF), known as a stress-related neuropeptide, increases the expression of both cyclooxygenase (COX) and nitric oxide synthase (NOS) in presympathetic neurons in the paraventricular hypothalamic nucleus (PVN). In the present study, therefore, we investigated whether brain COX and NOS can also mediate restraint stress (RS)-induced sympathetic activation by assessing the plasma catecholamine levels and neuronal activation of presympathetic neurons in the PVN. In addition, we examined effects of RS on the expression of both COX and NOS isozymes in the presympathetic PVN neurons. Intraperitoneal administration of an inhibitor for COX-1, COX-2 or inducible NOS (iNOS), but not for neuronal NOS (nNOS), reduced RS-induced elevation of plasma catecholamine levels and Fos expression in the presympathetic PVN neurons. Moreover, RS increased the expression of COX-1, COX-2 and iNOS in the presympathetic PVN neurons, whereas nNOS expression did not change. These results suggest that COX-1, COX-2 and iNOS in the presympathetic PVN neurons mediate acute RS-induced sympathetic activation.
压力是激活交感神经系统的重要因素之一。我们最近报道，作为一种与应激相关的神经肽，中枢给予促肾上腺皮质释放因子（CRF）可增加室旁下丘脑核（PVN）中交感前神经元中环氧化酶（COX）和一氧化氮合酶（NOS）的表达。因此，在本研究中，我们通过评估血浆儿茶酚胺水平和 PVN 中交感前神经元的神经元激活，研究了脑 COX 和 NOS 是否也可以介导束缚应激（RS）引起的交感神经激活。此外，我们还检查了 RS 对交感前 PVN 神经元中 COX 和 NOS 同工酶表达的影响。腹腔内给予 COX-1、COX-2 或诱导型 NOS（iNOS）抑制剂，但不是神经元 NOS（nNOS）抑制剂，可降低 RS 引起的血浆儿茶酚胺水平升高和 PVN 中交感前神经元的 Fos 表达。此外，RS 增加了交感前 PVN 神经元中 COX-1、COX-2 和 iNOS 的表达，而 nNOS 的表达没有变化。这些结果表明，交感前 PVN 神经元中的 COX-1、COX-2 和 iNOS 介导急性 RS 诱导的交感神经激活。
