CAJ | 학술논문

目的观察氧化应激对慢性心房快速起搏诱发心房颤动(房颤)犬心房肌钙激活蛋白酶Ⅰ表达及肌细胞超微结构改变的影响.方法 20只犬无菌条件下开胸手术,植入高频起搏器(400次/分),建立房颤犬模型,分为假手术组(不起搏),对照组和普罗布考组心房快速起搏6周.普罗布考组于起搏前1周服用普罗布考(100 mg/kg),至起搏6周结束.采用免疫组化方法和Western印迹法检测各组犬心房肌钙激活蛋白表达情况;分别于起搏前和起搏6周后,记录各组犬房颤诱发情况;比色法检测各组犬心房肌氧化应激相关指标.结果对照组左、右心房肌肌溶解比率[(53.6±11.8)%,(58.5±9.2)%]比假手术组[(4.4±3.1)%,(4.1±2.9)%]显著增加(P＜0.01);对照组比假手术组心房肌细胞线粒体肿胀伴糖原沉积明显,心房肌钙激活蛋白酶Ⅰ表达显著上调(P＜0.01);普罗布考组左、右心房肌细胞病理组织学和超微结构改变比对照组明显减轻,肌溶解比率明显减少[(12.3±3.2)%,(12.0±2.6)%,P＜0.01],钙激活蛋白酶Ⅰ表达显著下调(P＜0.01).普罗布考组心房肌MDA水平比对照组显著降低(P＜0.01),T-AOC和抗O2-水平明显增加(P＜0.01),房颤诱发率和平均持续时间显著减少(均P＜0.01).心房肌钙激活蛋白酶Ⅰ表达和MDA均与肌溶解程度呈显著正相关(r=0.958,r=0.939,P＜0.01).结论普罗布考能够通过抑制氧化应激,抑制房颤犬心房肌肌溶解等病理组织学和超微结构变化,防止心房颤动犬心房重构,减少房颤发生.
목적 관찰양화응격대만성심방쾌속기박유발심방전동(방전)견심방기개격활단백매Ⅰ표체급기세포초미결구개변적영향.방법 20지견무균조건하개흉수술,식입고빈기박기(400차/분),건립방전견모형,분위가수술조(불기박),대조조화보라포고조심방쾌속기박6주.보라포고조우기박전1주복용보라포고(100 mg/kg),지기박6주결속.채용면역조화방법화Western인적법검측각조견심방기개격활단백표체정황;분별우기박전화기박6주후,기록각조견방전유발정황;비색법검측각조견심방기양화응격상관지표.결과 대조조좌、우심방기기용해비솔[(53.6±11.8)%,(58.5±9.2)%]비가수술조[(4.4±3.1)%,(4.1±2.9)%]현저증가(P＜0.01);대조조비가수술조심방기세포선립체종창반당원침적명현,심방기개격활단백매Ⅰ표체현저상조(P＜0.01);보라포고조좌、우심방기세포병리조직학화초미결구개변비대조조명현감경,기용해비솔명현감소[(12.3±3.2)%,(12.0±2.6)%,P＜0.01],개격활단백매Ⅰ표체현저하조(P＜0.01).보라포고조심방기MDA수평비대조조현저강저(P＜0.01),T-AOC화항O2-수평명현증가(P＜0.01),방전유발솔화평균지속시간현저감소(균P＜0.01).심방기개격활단백매Ⅰ표체화MDA균여기용해정도정현저정상관(r=0.958,r=0.939,P＜0.01).결론 보라포고능구통과억제양화응격,억제방전견심방기기용해등병리조직학화초미결구변화,방지심방전동견심방중구,감소방전발생.
Objective To evaluate the effects of oxidative stress on the protein expression of atrial calpain Ⅰ and pathohistological and uhrastructural changes of atrial myocardium in atrial fibrillation(AF). Methods Twenty dogs were all implanted with pacemaker in a subcutaneous pocket and attached to a screw-in epicardial lead in right atrial appendage. They were randomly divided into 3 groups: sham-operation group(n=6 without pacing), control group(n=7 per minutes for 6 weeks), and probucol group(n=7, pacing till the end of pacing). One thin silicon plaque containing 4 pairs of electrodes were sutured to the right atrium. The dogs in control group, probucol group were paced at 400 beats per minutes for 6 weeks. Then the dogs were killed with their hearts taken out. The expression of atrial calpain Ⅰ was measured by Western-blotting and immunohistochemistry. The pathohistological and uhrastructural changes in atrial tissue were tested by light and electron microscopy. The inducibility and duration of AF were measured in the control group and probucol group. The indexes of oxidative stress total anti-oxidation capability(T-AOC), malonyldiadehyde(MDA), and scavenging activities of superoxide anion(O2-)radical were measured by colorimetric method. Results The percentage of myolysis in the left and right atria of the control group were (53. 6±11. 8)% and. (58. 5±9. 2)%respectively, significantly higher than those of the sham operation group[(4. 4±3. 1)% and. (4. 1±2. 9)% respectively, both P＜0. 01]. T The percentage ofmyolysis in the left and right atria ofthe probucol group were(12. 3±3. 2)% and (12. 0±2. 6)% respectively, both significantly lower than those of the control group(both P＜0. 01). The protein expression of calpain Ⅰ of the control group was significantly higher than that of the sham-operation group, and the protein expression of calpain Ⅰ of the probucol group was significantly lower than that of the control group. The AF inducibility rate after pacing of the probucol group was 60%, significantly lower than that of the control group(92. 9%, P ＜0. 01). The average AF duration time after pacing of the probucol group was(601±328)s, significantly shorter than that of the control group(1458±498)s. The indexes of oxidative stress in probucol group were lower than the level in control group. The MDA levels of the probueol group was(3. 08±0. 20)mmol/mg protein, significantly lower than that of the control group(4. 15±0. 23)mmol/mg protein). The anti-O2-and T-AOC level of the probucol group were 279±20 U/g protein and 30. 5±1. 3 nmol/mg protein, both significantly higher than those of the control group (215±16 U/g protein and 25. 6±1. 5 nmol/mg protein respectively, both P＜0. 01). There were more sarcomere vacuolization and dissolution in atrial myocytes in the control group than in the sham operation group. And the pathohistological and uhrastruetrual changes of the probueol were lighter than those of the control group. Conclusion Probucol prevents the pathohistological and ultrastruetural changes in atrial myocardium by inhibiting calpain Ⅰ expression, thus suppressing atrial structural remodeling, and preventing the induction and promotion of AF.