Sympathetic control and hypertension via brainstem cannabinoid signaling

通过脑干大麻素信号传导的交感神经控制和高血压

• 批准号: 8888884
• 负责人: Andrei Derbenev
• 金额: $ 38.77万
• 依托单位: TULANE UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8888884
• 关键词: Address; Agonist; Animals; Area; Blood Pressure; Brain; Brain Stem; Cannabinoids; Cardiovascular Physiology; Cardiovascular system; Cells; Clinical; Coupled; Data; Development; Disinhibition; Endocannabinoids; GTP-Binding Proteins; Glutamates; Goals; Heart Rate; Hypertension; Hypothalamic structure; In Vitro; Injection of therapeutic agent; Kidney; Lateral; Ligands; Light; Link; Measurement; Mediating; Medical; Microinjections; Mus; Nerve; Neural Pathways; Neuraxis; Neurons; Physiological; Play; Presynaptic Terminals; Rattus; Receptor Activation; Reflex action; Regulation; Renal function; Research Proposals; Role; Signal Transduction; Site; Spinal Cord; Structure; Suid Herpesvirus 1; Sympathetic Nervous System; Synapses; Telemetry; Testing; Tracer; Transgenic Mice; Vanilloid; Vasomotor; Viral; awake; base; blood pressure regulation; clinically significant; gamma-Aminobutyric Acid; hypertension control; hypertension treatment; in vivo; light effects; neural circuit; neurotransmission; novel therapeutics; optogenetics; patch clamp; receptor; response; treatment strategy

The overall goal of this research proposal is to assess the physiological significance of the endocannabinoids (eCBs) in the rostral ventrolateral medulla (RVLM) circuits which regulate cardiovascular function. The central nervous system is directly involved in the regulation of arterial blood pressure (ABP), largely through actions of the sympathetic nervous system on renal function and vasculature. The RVLM is a critical component in the central neural pathway since presympathetic RVLM neurons receive inputs from multiple brain areas and from the spinal cord, and thus mediate many cardiovascular reflexes. Hypertension may result from an imbalance between sympathetic vasomotor neuron activity and those cells that inhibit it. An increase in sympathetic nervous system activity is often associated with disinhibition of RVLM neurons; however, the underlying mechanisms remain unidentified. eCBs are endogenous ligands with a broad range of cardiovascular effects which activate: (1) G protein-coupled cannabinoid type-1 receptor (CB1R), (2) transient receptor potential vanilloid type 1 (TRPV1), or (3) both, indicating a duality of function. Our preliminary data demonstrate that activation of TRPV1 decreases both the excitability of presympathetic RVLM neurons as well as ABP and renal sympathetic nerve activity (RSNA). In addition, TRPV1 expressing neurons were identified in the lateral hypothalamus (LH) and these neurons project to the RVLM. Our multi-disciplinary approaches will use in vivo renal nerve and ABP recordings in rats following eCBs administration into RVLM, optogenetics in combination with telemetry measurements of ABP, fluorescent immunostaining, and in vitro patch-clamp recordings of synaptic currents in identified presympathetic RVLM neurons of transgenic mice. We will test the hypothesis that presympathetic RVLM neurons receive TRPV1 and CB1R expressing inhibitory inputs which determine the excitability of RVLM neurons and thus control ABP. Delineating these mechanisms of brainstem eCBs is essential to predict their impact on the central control of cardiovascular function caused by the activation of TRPV1 and/or CB1R. We believe our results will have clinical significance by providing direct evidence about the regulation of ABP by cannabinoids and will allow the development of novel therapeutic strategies for the treatment of hypertension.

本研究计划的总体目标是评估的生理意义