Correlation Between Electrophysiology And Histology Of The Pedunculopontine Nucleus And Parafascicular Nuclei In Rats

Parkinson’s Disease(PD)is a degenerative Disease of the central nervous system.The main cause is the degenerative loss of dopaminergic neurons in the midbrain substantia nigra pars compacta,which leads to multiple functional disorders in basal ganglia,cortex,thalamus and brainstem,and thus leads to a series of clinical symptoms of PD.Previous studies in our laboratory have shown that in addition to the degeneration and loss of neurons in the dense part of the substantia nigra,the Pedunculopontine nucleus(PPN)and Parafascicular nuclei(PF)in Parkinson’s disease model rats are characterized by varying degrees of neuronal degeneration and loss.This is consistent with the degeneration of neurons in the corresponding parts of the brain observed in the autopsy of PD patients.Therefore,our inference illustrates the crucial role of PPN and PF in PD.At present,electrical stimulation of PPN and CM-PF can significantly improve some symptoms that are difficult to be corrected by other treatments in PD patients.But the underlying pathophysiological mechanism is still unclear.Our laboratory previously studied the electrophysiological and histological changes of PPN and PF in normal and PD model rats,and confirmed the characteristics of electrophysiological and histological changes of PPN and PF in PD state.Plexon multi-channel signal acquisition system and immunofluorescence histology technology were applied in the experiment.The advantage is that the discharge of a single neuron can be collected,but the disadvantage is that the electrical signal and neuron transmitter type cannot be matched one to one in the classification of neurons.Electrical signals in order to solve the neurons and the neurons one-to-one neurotransmitter types and glass electrode is adopted in this experiment,using the neural biotin cell markers,collection and normal rats under anesthesia PPN and PF individual neurons in the electrical signal,at the same time using immunofluorescence histochemical staining techniques to analyze the records to electrical signals of single neurons of the neurotransmitter type,resulting in PPN and PF neurons in electrical signals and neurotransmitter type corresponding results.The following experimental results were obtained in this study:(1)The neurons in PPN were divided into three types by electrophysiological classification,and the above three types of neurons were identified as cholinergic neurons,γ-aminobutyric acid neurons and glutamate neurons by Jux Tac-Labelling and immunofluorescence double-labeling techniques.Among them,cholinergic neurons have the longest time span,lower discharge rate,regular discharge mode and the highest amplitude of trough and peak.γ-aminobutyric acid neurons have the shortest time span,lower firing rate,regular firing mode,and the amplitude of trough and peak is between cholinergic and glutamate neurons.The time course of glutamate neurons is between cholinergic neurons and γ-aminobutyric neurons.The firing rate is low,the firing mode is regular,and the amplitude of trough and peak is the lowest.(2)Similarly,PF neurons were divided into two types by electrophysiological classification,and the above two types of neurons were identified as γ-aminobutyrate neurons and glutamate neurons by Jux TAC-Labelling and immunofluorescence double-labeling techniques.Among them,γ-aminobutyric acid neurons have the shortest time span,lower firing rate and regular firing mode,and the amplitude of trough wave peak is basically the same as that of glutamate neurons.Glutamate neurons have the longest time span,lower firing rate and regular firing pattern.(3)The neuronal electrical signals of rats under anesthesia collected by the 6240 system and the neuronal electrical signals of rats under awake and static state collected by the Plexon multi-channel signal acquisition system were compared in terms of neuron time course and firing rate.To solve the problem of neuron electrical signal and transmitter type one-to-one correspondence.To sum up,the neurons in PPN mainly divided into three categories,PF neurons in the mainly divided into two categories,electrical signals by neurons and neural transmitter type one to one correspondence,can determine the electrical characteristics of different types of neurons,can more accurate judgment in the condition of PD,changes of different types of neurons and their corresponding changes in the electrical characteristics.It provides more accurate electrophysiological information for the research process of PD and makes the results more intuitive.