Effect of dapagliflozin on myocardial function changes in early spontaneously hypertensive rats: a study based on longitudinal layer-specific strain

Objective‍ ‍To evaluate the effect of dapagliflozin on myocardial function in early spontaneously hypertensive rats (SHR) with layer-specific global longitudinal strain (GLS). Methods‍ ‍A total of 45 male SHR aged 6 weeks were randomly divided into control group (normal saline), dapagliflozin group [1 mg/(kg·day)], and losartan group [10 mg/(kg·day)]. Fifteen male Wistar-Kyoto (WKY) rats at same age with normal blood pressure were subjected and served as blank control group. During 8 weeks of intervention, systolic blood pressure (SBP) was measured, and conventional echocardiography and two-dimensional speckle tracking echocardiography (2DSTE) were performed and the results were collected to acquire the longitudinal strain of each layer of left ventricular (LV) myocardium. The parameters were compared among the groups. The pathological changes of myocardium were observed in each group of rats. Results‍ ‍Compared with the WKY group, LV ejection fraction (LVEF) and LV fraction shortening (LVFS) at week 8 were decreased in the control group (P<0.05), but no such decreases were observed in the dapagliflozin group and the losartan group. The GLS of endo-myocardium (GLSendo) at the 6th week was decreased, and GLSendo, GLSmid and GLSepi at the 8th week were all decreased in the control group than the WKY group (all P<0.05). But there were no statistical differences in the above 3 indicators in the dapagliflozin and losartan groups when compared with the WKY group (all P>0.05). The pathological results showed that myocardial interstitial fibrosis was observed in the control group at the 6th week. Conclusion‍ ‍Dapagliflozin can effectively improve myocardial function in early SHR.