Activation of aortic baroreceptors depresses the somato-lumbar sympathetic reflex, reducing hindlimb muscle contractile force.

ABSTRACT: We investigated whether the same sympathetic nerves innervate arteries and neuromuscular junctions and aortic baroreceptor stimulation reduces muscle force in rats. Histological analysis with fluorescent labeling revealed nicotinic acetylcholine receptors, motor nerves, adrenergic nerves, and arteries in gastrocnemius muscle tissue. Whole-mount preparations revealed a potential extension of adrenergic nerves around an artery connected to the neuromuscular junction. Physiological analysis under anesthesia was conducted to examine the effects of baroreceptor activation on muscle contractility and contraction-induced lumbar sympathetic reflex discharges following tetanic motor nerve stimulation. Intravenous phenylephrine injection increased mean arterial pressure to ∼150 mmHg and reduced both

SUBMITTER: Watanabe N 

PROVIDER: S-EPMC12701687 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature