Rostral ventrolateral medulla spinal cord via reticulospinal tract. Physostigmine, a choline-esterase inhibitor, elevates endogenous levels of acetylcholine and causes a rise in blood pressure by stimulation of the RVLM. Orexinergic neurons from the lateral hypothalamus output in the RVLM. Rostral ventrolateral medulla The rostral ventrolateral medulla (RVLM), also known as the pressor area of the medulla, is a brain region that is responsible for basal and reflex control of sympathetic activity associated with cardiovascular function. Abnormally elevated sympathetic activity in the RVLM is associated with various cardiovascular diseases, such as heart failure and hypertension. The RVLM is notably involved in the baroreflex. It
Lateral hypothalamus neuropeptides orexin-A and orexin-B are the primary signaling neurochemicals in orexin neurons; pathway-specific neurochemicals include GABA, melanin-concentrating hormone, nociceptin, glucose, the dynorphin peptides, and the appetite-regulating peptide hormones leptin and ghrelin, among others. Notably, cannabinoid receptor 1 (CB1) is colocalized on orexinergic projection neurons in the lateral hypothalamus and many output structures, where the CB1 and orexin receptor 1 (OX1) receptors form the CB1–OX1 receptor heterodimer. The orexinergic projections from the lateral hypothalamus innervate the entirety of the remainder of the hypothalamus, with robust projections to the posterior hypothalamus, tuberomammillary nucleus (the histamine projection nucleus), the arcuate nucleus, and the