Modulated Roles Of MGlu5 Receptor On Rhythmic Respiratory Discharge Activity And Discharge Activities Of Inspiratory Neurons In MNRF Of Neonatal Rats In Vitro

BackgroudBiological survival by respiratory function.Medulla oblongata plays an indispensable role in the process of respiratory movement, facial nerve nucleus after medial area (the medial area of nucleus retrofacialis, mNRF) is located in the medulla oblongata ventrolateral area, is the key part of medulla oblongata basic rhythmic breathing to produce.Glutamate is widespread amino acids in the human body, not only as the basic structure of the protein in the human body composition, and as a neurotransmitter in the nervous system regulate the activity of the corresponding neurons. Study found that in front of the medulla oblongata mNRF breathing glutamate receptor neuron membrane, but metabolic glutamate receptor 5 (mGlu5R) whether to participate in the regulation of medulla oblongata respiratory function has not been reported, this study by observing the metabolic glutamate receptor 5 (mGlu5R) of newborn rat area contains mNRF medulla oblongata slices breathing discharge and inspiratory neurons and adjustment, to study the effect of mGlu5R, for further research on basic rhythmic breathing mechanism, regulation mechanism and central respiratory diseases provide clues and evidence for the prevention and cure.ObjectiveResearch mGlu5R for newborn rat in vitro medulla oblongata slices basic rhythmic breathing discharge and former BaoQin complex inspiratory neurons adjustment, for the prevention and treatment of central respiratory disease, provides a train of thought and experimental basis.Methods1. Using glass microelectrode and adsorption electrode recorded basic respiratory rhythm discharge and action potential of mNRF respiratory neurons of neonatal rat. The mGlu5R agonist DHPG and mGlu5R antagonists MPEP were perfused to slice to analysis the effect of mGlu5R on RRDA of neonatal rat.The slices were divided into 4 groups:Control group:those slices were perfused by ACSF on the brain slices of 60 min, in 15 min,30 min,45 min and 60 min to measure RRDA inspiratory time and integral discharge amplitude, respiratory cycle, respectively; Different concentration of DHPG groups:record RRDA 12 min, after using ACSF, different concentrations (1,2,4,8 μmol/L) DHPG were used to slices, each concentration 12 min, observe the change of RRDA; Different concentration of MPEP groups:different concentrations (0.5,1,2,4 μmol/L) of MPEP on the brain slices were perfused, each concentration 12 min, observe the change of RRDA; DHPG and DHPG+MPEP group: after recorded 12 min by ACSF, perfused by 4 mol/L DHPG 12 min, then perfused by 4 mol/L DHPG+2 mol/L MPEP 12 min after was out.2. Preparation of medulla oblongata in vitro of rats brain specimens, after RRDA,Recording action potential of mNRF respiratory neurons, perfused 4 μmol/L DHPG 15 min, then perfused 2umol/L MPEP 15min after was out.Statistical analysis to the medicine before, DHPG, flushing, MPEP about inspiratory neuron discharge.Results1. The inhibitory effect of DHPG on RRDA 2 mol/L is inhibited,4 mol/L inhibition of RRDA reached the maximum effect. The exciting effect of MPEP on MPEP 1 mol/L is inhibited,2 mol/L exciting of RRDA reached the maximum effect.4 mol/L DHPG+2 mol/L MPEP can block the exciting effect of DHPG to RRDA.2. DHPG increased the excitability of inspiratory neurons in mNRF, MPEP decreased the excitability of inspiratory neurons in mNRF.ConclusionsIn newborn rats medulla oblongata mNRF area, physiological conditions exist Glu, mGlu5R inspiratory neuron membrane, mGlu5R basic rhythmic breathing of newborn rat medulla oblongata discharge and mNRF area inspiratory neurons discharge behavior plays a positive adjustment.