<Tr> <Th> Acronym (s) </Th> <Td> VMC </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terminology (edit on Wikidata) </Td> </Tr> <P> The vasomotor center (VMC) is a portion of the medulla oblongata that, together with the cardiovascular center and respiratory center, regulates blood pressure and other homeostatic processes . Vasomotor center is a fairly archaic term since this function relies not on a single brain structure ("center") but rather represents a presympathetic network of interacting neurons . Upon increase in carbon dioxide level at central chemoreceptors, it stimulates the sympathetic system to constrict vessels . This is opposite to carbon dioxide in tissues causing vasodilatation, especially in the brain . Cranial nerves IX (Glossopharyngeal nerve) and X Vagus nerve both feed into the vasomotor centre and are themselves involved in the regulation of blood pressure . The localization of VMC was determined by Filipp Ovsyannikov in 1871 . </P>

Where are the main vasomotor cardio inhibitory and respiratory centers located
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