<prompt> Major neurotransmitter in afferents in nucleus tractus solitarius to regulate cardiovascular system -SerotoxinGlutamateGlycineNorepinephrine  <response>: Ans. is b i.e., Glutamate o Nucleus tractus solitarius NTS lies in medulla.o It receives following afferents :-General visceral afferentsFrom tonsil, pharynx, posterior part of tongue, carotid body and sinus - through glossopharyngeal nerve:From pharynx, larynx, trachea, esophagus, and other thoracic and abdominal viscera -through vagus nerve.Special visceral afferentsFrom anterior 23 of tongue except circumvallate papillae and palate - through facial nerveFrom posterior 13 of tongue including circumvallate papillae - through glossopharyngeal nerve.From posterior most part of tongue and epiglottis - through vagus nerve.o NTS is involved in regulation of cardiovascular system through baroreceptors and chemoreceptors.o There is a general consensus that glutamate is the neurotransmitter released at the therminals of baroreceptor and chemoreceptor afferents in NTS. -- However, cholinergic, GABAergic, and opioidergic mechanisms are also present in NTS. 