In the paraventricular nucleus (PVN) of the hypothalamus, nitric oxide (NO) inhibits sympathetic outflow through increased GABA release. However, the signal transduction pathways involved in its action remain unclear. In the present study, we determined the role of cGMP, soluble guanylyl cyclase, and protein kinase G in the potentiating effect of NO on synaptic GABA release to spinally projecting PVN neurones. The PVN neurones were retrogradely labelled by a fluorescent tracer injected into the thoracic spinal cord of rats. Whole-cell voltage-clamp recordings were performed on labelled PVN neurones in the hypothalamic slice. Bath application of the NO donor, S-nitroso-N-acetyl-penicillamine (SNAP), reproducibly increased the frequency of miniature GABAergic inhibitory postsynaptic currents (mIPSCs) without changing the amplitude and the decay time constant. Neither replacement of Ca2+ with Co2+ nor application of Cd2+ to block the Ca2+ channel altered the effect of SNAP on mIPSCs. Also, the effect of SNAP on mIPSCs was not significantly affected by thapsigargin, a Ca2+-ATPase inhibitor that depletes intracellular Ca2+ stores. Application of a membrane-permeant cGMP analogue, pCPT-cGMP, mimicked the effect of SNAP on mIPSCs in the presence of a phosphodiesterase inhibitor, IBMX. Furthermore, both the soluble guanylyl cyclase inhibitor, ODQ, and the specific protein kinase G inhibitor, Rp pCPT cGMP, abolished the effect of SNAP on mIPSCs. Thus, these data provide substantial new information that NO potentiates GABAergic synaptic inputs to spinally projecting PVN neurones through a cGMP-protein kinase G pathway.
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http://dx.doi.org/10.1113/jphysiol.2003.053371 | DOI Listing |
The bed nucleus of the stria terminalis (BNST) is involved in feeding, reward, aversion, and anxiety-like behavior. We identify BNST neurons defined by the expression of vesicular glutamate transporter 3, VGluT3. VGluT3 neurons were localized to anteromedial BNST, were molecularly distinct from accumbal VGluT3 neurons, and co-express vesicular GABA transporter (VGaT).
View Article and Find Full Text PDFAndrology
January 2025
Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Background: Although some studies have revealed the close relationship between leptin and premature ejaculation in clinical practice, whether and how leptin participates in the regulation of ejaculatory behaviors are still unknown.
Objective: To explore the role of leptin on ejaculatory behaviors and its underlying mechanism.
Materials And Methods: Copulation behavior tests were performed after acute and chronic leptin administration at peripheral and central levels.
Behav Brain Res
March 2025
Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. Electronic address:
Acting centrally, dopamine has been shown to induce ergogenic effects derived from its influence on thermoregulation, motivation, reward, and motor control. Thus, to evaluate the role of the central dopaminergic system in hypothalamic neuronal activation and its relationship with exercise performance, Wistar rats were intracerebroventricularly injected with saline (SAL) or SCH-23390 (SCH, dopamine D1 receptor blocker) at rest and before timed submaximal exercise (∼13 min) or exercise until fatigue. Core body and tail temperatures were recorded throughout the exercise.
View Article and Find Full Text PDFBMC Biol
December 2024
Key Laboratory of Environmental Stress and Chronic Disease Control & Prevention Ministry of Education, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning, 110122, People's Republic of China.
Background: Epidemiologic researches show that short sleep duration may affect feeding behaviors resulting in higher energy intake and increased risk of obesity, but the further mechanisms that can interpret the causality remain unclear. The circadian rhythm is fine-tuned by the suprachiasmatic nucleus (SCN) as the master clock, which is essential for driving rhythms in food intake and energy metabolism through neuronal projections to the arcuate nucleus (ARC) and paraventricular nucleus (PVN).
Results: We showed that chronic SD-induced aberrant expressions of AgRP/NPY and POMC attributed to compromised JAK/STAT3 signals and reduced energy expenditure in the mice, which can be rescued with AAV-genetic overexpression of BMAL1 into SCN.
Peptides
December 2024
Department of Special Medicine, School of Basic Medicine, Qingdao University, Qingdao 266000, China. Electronic address:
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