Abstract 072: Brain Epithelial Sodium Channels on Organum Vasculosum of the Lamina Terminalis Neurons Mediate Sympathoexcitatory Pressor Responses and Neuronal Excitation by Hypertonic NaCl
| Autor: | Sean D. Stocker, Kirsteen N. Browning, Brian J. Kinsman |
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| Rok vydání: | 2016 |
| Předmět: | |
| Zdroj: | Hypertension. 68 |
| ISSN: | 1524-4563 0194-911X |
| DOI: | 10.1161/hyp.68.suppl_1.072 |
| Popis: | High dietary salt intake raises cerebrospinal fluid (CSF) [Na + ] in salt sensitive subjects to elevate sympathetic nerve activity (SNA), and arterial blood pressure (ABP). This occurs through excitation of NaCl-sensitive sites in the brain, including the organum vasculosum of the lamina terminalis (OVLT). Intriguingly, intracerebroventricular (ICV) pretreatment with benzamil (a non-voltage gated Na + channel blocker) also attenuates those systemic responses to central NaCl. Thus, I hypothesized that benzamil acts on NaCl-sensitive OVLT neurons to attenuate neuronal excitation and elevated SNA and ABP in response to hypertonic NaCl. To evaluate this hypothesis, lumbar SNA and ABP were measured in anesthetized adult rats in response to ICV infusion of 0.15, 0.5, and 1.0 M NaCl with and without prior OVLT microinjection of benzamil (5nmol per 20nL). ICV infusion of NaCl produced concentration-dependent increases in lumbar SNA (0.15M: 101±3%, 0.5M: 118±3%, 1.0M: 130±9% n=4 per group, P0.05). Collectively, this data indicates that elevations in CSF NaCl concentrations excite OVLT neurons via ENaC to elevate SNA and ABP. |
| Databáze: | OpenAIRE |
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