The Glutamate-ionic Receptors Of MVN Involved In The Regulation Of NE In Serum

Aim:In 1998,some scholars put forward,The central pathway of vestibular sympathetic reflex.That is the vestibular organs-the vestibular nerve(VN)-the Lateral medulla oblongata reticular structure-RVLM-The spinal cord grey matter side Angle-sympathetic nerve。This research use immune histochemical method was found,the NMDA and AMPA receptor in MVN participate in the regulation of vestibular blood pressure by acute hypotension induced,increase the concentration of serum epinephrine increased significantly.The main source of adrenaline in the body is adrenal medulla,and the norepinephrine is secreted by the adrenal medulla and sympathetic postganglionic neurons.The norepinephrine in the blood can reflect the state of the sympathetic nervous system.Whether there is sympathetic nerve involvement in the regulation of blood pressure by the peripheral vestibular organ have no relevant research reports.The purpose of this study was to investigate the effect of acute hypotension on vestibular blood pressure regulation,Effects of partial ionotropic receptors of Glutamate in MVN on serum norepinephrine.At the same time,confirmed that SNP induced acute hypotension by western blot analysis。The effects of Glutamate receptors agonists and antagonists in MVN on the expression of c-Fos and p-ERK1/2 protein in thoracic segment of spinal cord,To prove acute hypotension,The Glutamate receptors in the MVN was excited and to effect the blood pressure regulation by excitement the spinal sympathetic nerve。Method:First,in order to exclude the effect of the Pressure sensors on the change of blood pressure regulation,anesthetized animals and remove the pressure receptor of Carotid Sinus and aortic arch,Eliminate the role of stress receptors on blood pressure regulation.Monitoring the changes of the Blood pressure and baroreflex sensitivity in the animals,by the Multi-channel physiological recorder to determine whether the model was success.After the model operation.The 36 SD rats were divided into group of blockers(control group,CNQX Group and MK-801 group,all of these group were Induced Hypotension)and agonist(control group,NMDA Group and AMPA Group,)randomly,none of these group were Induced Hypotension).Inject the agonist 100mol/ml,agonist 200mol/ml and ACSF(artificial cerebrospinal fluid,for control group)by the Micro injection pump,and Set the flow rate is 1.5μl/min,time is 5 min.The next day,after the rat awake,medial vestibular nuclei inject agonist and intravenous sodium nitroprusside after 10 min,prepare the model of acute hypotension.But agonist group is not given Sodium nitroprusside,then the rat was Stretched neck to paralyzed,Open chest and expose the heart with scissors,Removed the heart blood by using coagulation promoting tube of vacuum,Separation serum by centrifuge,set 3000r/min,time 10 min,the serum was saved in-80℃ refrigerator,Check the NE content in serum by using ELASA.At the same time,Mash T5 spinal cord of experimental animal,After Lysis protein to test the expression of p-ERK1/2 and c-Fos protein by Western Blot analysis.Result:1.After injection the Glutamate receptors blocker CNQX or MK-801 and acute hypotension,find that c-Fos and p-ERK1/2 protein were significantly lower than that in control group(P<0.05,n=6).2.After injection the Glutamate receptors agonist(NMDA/AMPA),find that c-Fos and p-ERK1/2 protein were significantly higher than that in control group(P<0.05,n=6).3.After injection the Glutamate receptors blocker CNQX or MK-801 and acute hypotension,find that levels of norepinephrine in Serum were significantly lower than that in control group(P<0.05,n=6).4.After injection the Glutamate receptors agonist(NMDA/AMPA),find that levels of norepinephrine in serum were significantly higher than that in control group(P<0.05,n=6).Conclusion:The sympathetic nerve was activated by the Glutamate ionic-receptors(NMDA/AMPA)in the MVN to increase serum NE during hypotension...