After Intravenous Injection Of Pituitary Vasopressin Neurons In The Medullary Visceral Zone Morphology Of The Reaction And The Edge Structure Of Regulation And Physiological Study

Medulla oblongata is thought of as a primary center in regulating the basic vital functions, such as cardiovascular, respiratory or gastro-intestinal activities. But there are lots of problems remained unanswered about it's exact location, enclosed nuclei, functions, as well as it's connections with other nuclei.Professor Rao Zhiren and his group have devoted much efforts to the investigation of this center within recent decades. As a result, an arch-shaped area was found to be situated in the middle-caudal medulla oblongata in the rat, monkey, and human fetus. In rat, from 0.8mm rostral of obex to 1.0mm caudal of obex, this area is 1.8mm long and 0.6-1.3mm wide. In the case of the monkey it is 8mm long and 0.9-2.5mm wide. We named it "medullary visceral zone (MVZ)", for it contains several nuclei (NTS, NDMX, Amb, etc.) which are implicated in regulating visceral functions. Many kinds of neuro-active substances, including neurotransmitters, receptors, and neurotransmitter transporters, have been concomitantly identified in both the dorso-medial and ventro-lateral portions, and also the transitory area between the two regions in MVZ, thus forming an arch-shaped zone. It is interesting that every part in the zone shares common efferent or afferent connections. FOS protein was expressed in neurons of MVZ following visceral organs (stomach or heart) and somatic (forearm) stimulation suffered from noxious stimulation, suggesting that MVZ is involved in the modulation of visceral or somatic noxious information.Our experiments are aimed at finding the morphologic and eletrophysiological evidence on that Ce is involved in the neuromodulation of cardiovascular stress information mediated by MVZ.As we know, FOS protein is one of stress-induceable proteins. Substance P receptor receives noxious information conveyed by the release of SP. In our experiments, immunohistochemistry methods were used to investigate the distribution of FOS protein, the changes of substance P receptor, and also the coexistence of FOS and TH (tyrosine hydroxylase) , FOS and SPR, SPR and TH in MVZ of rat with cardiovascular stress induced by intraveneous injection of...