Orexin A in rat rostral ventrolateral medulla is pressor sympatho-excitatory increases barosensitivity and attenuates the somato-sympathetic reflex

摘要

BACKGROUND AND PURPOSEThe rostral ventrolateral medulla (RVLM) maintains sympathetic nerve activity (SNA), and integrates adaptive reflexes. Orexin A-immunoreactive neurones in the lateral hypothalamus project to the RVLM. Microinjection of orexin A into RVLM increases blood pressure and heart rate. However, the expression of orexin receptors, and effects of orexin A in the RVLM on splanchnic SNA (sSNA), respiration and adaptive reflexes are unknown.