Influenc of insulin resistance and isosorbide mononitrate on myocardial cellular apoptosis in spontaneously hypertensive rats / 重庆医学

ABSTRACT

Objective To observe the influence of insulin resistance(IR) and isosorbide mononitrate(ISMN) on myocardial cellular apoptosis in spontaneously hypertensive rats (SHR) .Methods Forty male 14‐week old Wistar(W) rats and SHR(S) each were respectively or jointly fed with normal diet (ND) ,high fat and high glucose(HFHG) diet ,normal saline(NS)and ISMN by ga‐vage .Then they were randomly divided into the normal and NS group (normal W and normal S ) ,HFHG and NS group(HFHG W and HFHG S) ,normal and ISMN group(ISMN W and ISMN S) ,HFHG and ISMN group(HI W and HI S) ,with 10 rats in each group .After 12‐week feeding ,carotid arterial blood was collected for detecting blood glucose concentration and insulin level and cal‐culating insulin resistance index (HOMA‐IR);4 myocardial tissue samples were taken for respectively observing the morphology under microscope ,and detecting the NO level ,myocardial Bcl‐2 ,Bax gene and their protein expression levels in myocardial tissue . Results Myocardial NO level ,Bax gene mRNA and related protein levels in the HFHG and ISMN intervention groups were higher than those in the normal group ,while the bcl‐2 gene mRNA and related protein expression were on the contrary ;myocardial tissue NO level ,Bax gene mRNA and related protein expression in the S groups were increased compared with the corresponding W groups ,while the bcl‐2 gene mRNA and related protein expression were on the contrary ;in the HFHG W group ,the myocardial tis‐sue NO level had significantly positive correlation with HOMA‐IR ,and in the ISMN W group ,HOMA‐IR was positively correlated with the NO level in the myocardial tissue .Conclusion Myocardial cellular apoptosis of SHR is increased compared with Wistar rats ;both IR and ISMN can aggravate the apoptosis of SHR myocardial cells ,moreover IR has a mutual induction and reciprocal causation with ISMN .