Transverse section of medulla oblongata of human embryo. Bodies that matter pdf tractus solitarius medullae oblongatae.
Through the center of the SN runs the solitary tract, a white bundle of nerve fibers, including fibers from the facial, glossopharyngeal and vagus nerves, that innervate the SN. The SN projects to, among other regions, the reticular formation, parasympathetic preganglionic neurons, hypothalamus and thalamus, forming circuits that contribute to autonomic regulation.
Neurons that innervate the SN mediate the gag reflex, the carotid sinus reflex, the aortic reflex, the cough reflex, the baroreceptor and chemoreceptor reflexes, several respiratory reflexes and reflexes within the gastrointestinal system regulating motility and secretion. Neurons which transmit signals about the gut wall, the stretch of the lungs, and the dryness of mucous membranes also innervate the SN. The first central neurons within the SN can participate in simple autonomic reflexes.
The signals projected from the SN to the parabrachial area originate in the oral cavity and gastrointestinal tract. Some neuronal subpopulations in the SN, such as the noradrenergic cell group A2 and the aldosterone-sensitive HSD2 neurons project as far rostrally as the bed nucleus of the stria terminalis.
Section of the medulla oblongata at about the middle of the olive. Neuroanatomy: An Atlas of Structures, Sections, and Systems.
Oral and gastric input to the parabrachial nucleus of the rat”. Differential projections from gustatory responsive regions of the parabrachial nucleus to the medulla and forebrain”. Aldosterone-sensitive neurons in the nucleus of the solitary tract: efferent projections. Shin JW, Geerling JC, Loewy AD.