ABSTRACT
Objective To study the level of serum lipids and body-fat content of high-fat diet induced pbesity rats(DIO).explore the relationship between intracellular caleium and ventrieufar arrhythmia.Methods Sixty male Sprague-Dawley(SD)rats were divided into control group(15)and experiment group(45),high-fat diet was administrated for 12 weeks to established obesity model,15 rats were selected into obesity group according to their body weight gain.The standard 2-lead electrocardiograph was used to detect the incidence and scores of arrhythmia induced by barium chloride(BaCl2,0.1 mg/kg)for 1 hour on every 8 rats from different groups respectively.Body-fat content.the level of serum total cholesterol(TC),triglyceride(TG),low density lipopmtein cholesterol (LDL-C) and high density lipopmtein cholesterol (HDL-C)were measured.The epididymal(EP),retroperitoneal (RE) and mesenteric(ME)white adipose pads was measured to obtain the body fat content.Single ventricular myrocytes of rats were isolated by enzymatic dissociation.The confocal laser scanning microscope was used to record basic intraceUular calcium level([Ca2+]i).Results The body-fat content in obesity group[(7.71±0.74)%] was significantly higher than control group[(4.69±0.37)%](t＝3.650,P＜0.05).The level of serum TC,TGand LDL-C were significantly higher(t＝3.801,2.778,3.536.P＜0.05) in obesity group[(1.26±0.04),(0.58±0.10),(0.51±0.04)mmol/L]than those in control group[(0.92±0.08),(0.29+0.03),(0.31±0.04) mmol/L].The level of serum HDL-C wa8 decreased gradually from control group[(0.53±0.05)mmol/L] toobesity group[(0.52±0.02)mmol/L],but there waft no significant difference between them(t＝0.186,P＞0.05).The incidence of arrhythmia induced by BaCl2(0.1 mg/kg)in obesity group was significantly higher than controlgroup(X2＝5.333,P＜0.05),and the scores of arrhythmla was increased in obesity group(2.5±0.6)too.The fluorescence intensity standing for[Ca2+]i was increased significantly(t＝2.409,P＜0.05)from obesity group(247.96±20.03)to control group (174.25±23.13).Conclusion As the free cytosolic calcium begin to accumulate,the arrhythmia morbidity is increased in obesity rats.