Alteration Of M3Receptor In Smooth Muscle On Rat Of Partial Unilateral Ureteral Obstruction

Objective:To determine the Alteration of M3receptor in smooth muscle in rats after partial unilateral ureteral obstructed.Method: Eighty male Wistar rats have been randomly divided into four groups:8-week experimental group (n=20) and sham control group (n=20),16-week experimental group (n=20) and sham control group (n=20). Experimental animals’left ureters (n=40) have been embedded the upper half into the psoas muscles. Sham control rats only received laparotomy. The ureters were cut at different experimental time points after the model had been established. We detected mRNA expression of M3receptor and the protein expression of M3receptor by the RT-PCR and Western-blotting, compared the M3receptor expression between the different groups. An independent sample t-test (Statistical Package for the Social Sciences, SPSS15.0) was performed to analyze the M3receptor protein expression levels. Differences with p<0.05were considered statistically significant.Results:According to the results of RT-PCR, the mRNA expression level of M receptor in8-week experimental groups was significantly higher than sham groups55.16±3.94VS36.48±3.87(P<0.05), but lower than sham groups at16-weekl9.37±3.70VS37.39±3.65(P<0.05),8weeks experimental group was higher than the16weeks experimental group (P<0.05). Western blotting experiments indicated that the experimental group, the M3receptor protein expression levels in the eight weeks of partial unilateral ureteral obstructed was higher, that is27.13±1.77VS21.36±2.69(P<0.05);16weeks lower than the control group, that is19.41±1.37VS23.43±1.58(P<0.05). The correlation analysis suggested that the ureteral smooth muscle M3receptor mRNA expression levels with the M3receptor protein expression level of positive correlation (P<0.05). And8weeks in the control group and16weeks in the control group were with no significant difference (P>0.05).Conclusion: It Demonstrates an increase of M3receptor in smooth muscle in PUUO rats at eight weeks while a decrease at sixteen weeks and it provides a molecular mechanism for dynamic changes of the increased smooth muscle contractility at early stage,while the decreased at late stage in PUUO.