Circuit-Specific Control of Blood Pressure by PNMT‑Expressing Nucleus Tractus Solitarii Neurons
Shirui Jun1 · Xianhong Ou2 · Luo Shi1 · Hongxiao Yu1 · Tianjiao Deng1 · Jinting Chen3 · Xiaojun Nie1 · Yinchao Hao1 · Yishuo Shi1 · Wei Liu1 · Yanming Tian1 · Sheng Wang1,4 · Fang Yuan1,41 Department of Neurobiology, Hebei Medical University, Shijiazhuang 050017, China
2 Institute of Cardiovascular Research, Southwest Medical University, Luzhou 646000, China
3 Core Facilities and Centers, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang 050017, China
4 Hebei Key Laboratory of Neurophysiology, Shijiazhuang 050017, China
Abstract
The nucleus tractus solitarii (NTS) is one of the morphologically and functionally defined centers that engage in the autonomic regulation of cardiovascular activity. Phenotypically-characterized NTS neurons have been implicated in the differential regulation of blood pressure (BP). Here, we investigated whether phenylethanolamine N-methyltransferase (PNMT)-expressing NTS (NTSPNMT) neurons contribute to the control of BP. We demonstrate that photostimulation of NTSPNMT neurons has variable effects on BP. A depressor response was produced during optogenetic stimulation of NTSPNMT neurons projecting to the paraventricular nucleus of the hypothalamus, lateral parabrachial nucleus, and caudal ventrolateral medulla. Conversely, photostimulation of NTSPNMT neurons projecting to the rostral ventrolateral medulla produced a robust pressor response and bradycardia. In addition, genetic ablation of both NTSPNMT neurons and those projecting to the rostral ventrolateral medulla impaired the arterial baroreflex. Overall, we revealed the neuronal phenotype- and circuit-specific mechanisms underlying the contribution of NTSPNMT neurons to the regulation of BP.
Keywords
Nucleus tractus solitarii; Blood pressure; Rostral ventrolateral medulla; Optogenetics; Neural circuit
