Study On The Correlationc Between Holine Receptor And The Transcription Of FOS Protein Gene In Mouse Brain

Fos gene exists in many types of cells,C-fos gene is involved in cell growth,differentiation,information transmission and other physiological functions,which is characterized by the rapidly and instantaneously expression of fos protein in quiescent cells when it was stimulated by the outside.The pathway of cholinergic nerve is an important part for learning memory and its functional state is closely related to memory.This study aims were to explore the molecular mechanism of learning and memory affected by choline receptor ligand in mice through investigating the effects of learning and memory process,cholinergic receptor agonists and inhibitors on the transcription level of c-fos gene in the hippocampus.The test results are as follows:(1)A memory maze model was established to train mice memory.The trained mice remembered the path of the maze model and were able to quickly find the escape platform.The results showed that the average speed at which the untrained blank group could find the escape hatch was 5.868cm/s.After six days of training,the mice remembered the maze model's escape hatch.The average speed of finding escape windows from initial points of B/C/D/E in the maze was 20.554 cm/s,20.888cm/s,22.420 cm/s,and 20.471 cm/s respectively,which was much higher than the blank group.(2)The transcriptional levels of c-fos gene in mice hippocampal tissues after training and untrained were detected by qRT-PCR method,to explore the correlation between the results of memory training and the transcriptional levels of c-fos gene in mice.Results show that the transcription level of fos gene in trained rats hippocampal tissues of B/C/D/E groups were B(1.943±0.112),C(2.131±0.194),D(2.090±0.144),and E(2.052±0.174)respectively.the transcription level of fos gene in untrained rats of the blank group and the experimental model group were 0.992±0.000,1.012±0.000 respectively.It showd that the ranscription levels of c-fos gene in trained mice was upregulated significantly(p?0.01).(3)QRT-PCR method was used to investigate the effects of choline receptor agonist(rutin)and receptor blocker(atropine)on c-fos gene transcription in the hippocampus of mice.The results show that:Cholinergic receptor blocker(atropine)can down-regulate the transcription of c-fos gene in the hippocampus of mice,and the effect is the most obvious under the condition of 0.3mg/kg and 2.5h,which is significantly different from the control group(p?0.01).With the extension of treatment time,it decreased from 1.5h to 2.5h,and then gradually increased to 3.5h,close to the blank group.Cholinergic receptor agonist(rutin)could up-regulate the transcription of c-fos gene in the hippocampus of mice,and the effect was most obvious at 15mg/kg and2.5h,which was significantly different from the control group(p?0.01).From 1.5h,upregulation appeared,reaching the highest level at 2.5h,and then gradually decreased towards the blank group at 3.5h.(4)the effects of choline receptor agonist--rutin and receptor blocker--atropine on FOS protein expression in the hippocampus of mice were investigated by Elisa.The results show that:FOS protein expression in the hippocampus of mice in the blank control group was low,with the highest 164.9 pg/mLand the lowest 94.309 pg/mL,and the average was 151.83 pg/mL.FOS protein expression in the posterior hippocampus of mice in the model group was low,with the highest expression of 179.4 pg/mL and the lowest expression of 132.00 pg/mL,respectively.This indicated that in the experimental process,the stimulation of hand grasping behavior and other conditions in mice had no effect on the expression of FOS protein in the hippocampus of mice,so the error effect was excluded.After 2.5 h of atropine treatment at 0.03 mg/kg,FOS protein expression in the hippocampus of mice had the highest level of 179.41 ng/mL and the lowest level of 124.68.00 pg/mL,with an average level of 156.98 pg/mL.The difference between the two groups was not significant.The results showed that choline receptor inhibitor had no significant effect on FOS protein expression in thehippocampus of mice.After 2.5h of rutin treatment at 15 mg/kg,FOS protein expression in the hippocampus of mice was significantly increased,with the highest expression reaching 283.332 pg/mL,the lowest expression 221.871 pg/mL,and the average expression being 259.70 pg/mL.The difference between model group and blank group was significant.The results indicated that choline receptor agonist had up-regulation effect on FOS protein expression in hippocampus of mice,and the effect was more obvious than that of blank group and experimental model group.Conclusion: the enhancement of memory function in mice was related to the up-regulation of c-fos gene expression and the enhancement of FOS protein expression in the hippocampus.Cholinergic nerve pathway is closely related to memory,choline agonists-jaborandi alkali can increase mice hippocampus c-fos protein gene transcription,enhance the expression of FOS protein,therefore,choline agonists improve memory function is through the mice hippocampus c-fos gene transcription level,strengthen the c-fos protein expression.