Phenotypic transformation of bladder smooth muscle in diabetic rats

  OBJECTIVE: To detect the expression levels of bladder smooth muscle contractile markers and key regulatory gene myocardin in diabetic SD rats 9 weeks after the establishment of streptozotocin, and to understand whether the bladder smooth muscle of diabetic rats undergoes phenotypic transformation.

  Methods: Thirty-two 8-week-old male SD rats weighing 200-220 g were randomly divided into diabetic (DM) and non-diabetic (NDM) groups. After 9 weeks, bladder tissues were taken for HE and Masson trichrome staining to observe the bladder Histopathological changes, qRT-PCR, Western blotting were used to detect bladder tissue smooth muscle actin (α-SMA), smooth muscle myosin heavy chain contractile smooth muscle markers, and the mRNA and protein expression levels of myocardin gene.

  Results: Compared with the NDM group, rats in the DM group were significantly thinner (286.25±71.20 g vs 412.71±102.74 g, P=0.001), polydipsia, polyuria, increased collagen fibrous tissue in the bladder (P<0.001), myocardin, α-SMA The mRNA and protein levels of smooth muscle myosin heavy chain decreased significantly (all P<0.05).

  Conclusion: The bladder smooth muscle of diabetic rats undergoes phenotypic transformation at 9 weeks after modeling, which causes the bladder smooth muscle relaxation and contraction disorder, which may play an important role in the pathological changes of the diabetic bladder.