褪黑素受体1A/B敲除对小鼠心房老化进程的影响  

Melatonin receptor 1A/B knockout accelerates atrial aging in mice

作　　者：冯振宇 夏云龙[1] 谢云鹏 FENG Zhenyu;XIA Yunlong;XIE Yunpeng(Department of Cardiology,the First Affiliated Hospital of Dalian Medical University,Dalian 116011,China)

机构地区：[1]大连医科大学附属第一医院心内科,辽宁大连116011

出　　处：《大连医科大学学报》2024年第6期488-496,502,共10页Journal of Dalian Medical University

基　　金：国家自然科学基金项目(82070380);辽宁省自然科学基金项目(2024-MS-160)。

摘　　要：目的探讨褪黑素受体1A(MT1)和褪黑素受体1B(MT2)敲除对老化相关心房颤动(AF)的影响。方法将雄性C57BL/6J小鼠分为6组:8周对照组:野生型,6只,8周龄,体重21~23 g;8周MT1组:MT1敲除,6只,8周龄,体重21~23 g;8周MT2组:MT2敲除,6只,8周龄,体重21~23 g;12个月对照组:野生型,6只,12月龄,体重24~28 g;12个月MT1组:MT1敲除,6只,12月龄,体重24~28 g;12个月MT2组:MT2敲除,6只,12月龄,体重24~28 g。通过超声检测6组小鼠的左心房(LA)内径,电刺激评估小鼠AF诱导率及时间。通过HE染色、Masson染色、DHE染色、TUNEL凋亡染色、免疫荧光染色以及免疫组化染色评估小鼠心房炎症、纤维化、氧化应激和细胞凋亡水平。结果超声心动图显示,与8周MT1组比较,12个月MT1组小鼠的LA内径明显增大;与12个月对照组比较,12个月MT1组小鼠的LA内径增大,差异均有统计学意义(P<0.05)。电刺激结果显示,与8周MT1组比较,12个月MT1组小鼠的AF诱导率与持续时间明显提高,差异有统计学意义(P<0.05)。炎症指标:iNOS免疫组织化学染色结果显示,与8周各组比较,12个月对照组、MT1及MT2组小鼠心房iNOS的表达均增加;与12个月对照组比较,12个月MT1、MT2组小鼠心房iNOS的表达增加,差异均有统计学意义(P<0.05)。纤维化水平指标:Masson染色显示,与8周各组比较,12个月对照组、MT1及MT2组小鼠心房纤维化水平均增加;与12个月对照组比较,12个月MT1、MT2组小鼠的心房纤维化水平增加,差异均有统计学意义(P<0.05)。免疫荧光染色结果显示,与8周各组比较,12个月对照组、MT1及MT2组小鼠心房Ⅲ型胶原蛋白(CollagenⅢ)的表达水平均增加;与12个月对照组比较,12个月MT1、MT2组小鼠心房CollagenⅢ的表达水平增加,差异均有统计学意义(P<0.05)。α-SMA免疫组织化学染色结果显示,与8周各组比较,12个月对照组、MT1及MT2组小鼠心房α-SMA的表达均增加;与12个月对照组比较,12个月MT1、MT2组小鼠心Objective To investigate the effects of melatonin receptor 1A(MT1)and melatonin receptor 1B(MT2)knockout on age-related atrial fibrillation(AF).Methods Male C57BL/6J mice were divided into 6 groups:8-week control group(n=6,wild type,8 weeks old,weight 21-23 g);8-week MT1 group(n=6,MT1 knocked out,8 weeks old,weight 21-23 g);8-week MT2 group(n=6,MT2 knocked out,8 weeks old,weight 21-23 g);12-month control group(n=6,wild type,12 months old,weight 24-28 g);12-month MT1 group(n=6,MT1 knocked out,12 months old,weight 24-28 g);12-month MT2 group(n=6,MT2 knocked out,12 months old,weight 24-28 g).Left atrial(LA)diameter was measured by echocardiography and AF induction rate and during were evaluated by electrical stimulation.Atrial fibrosis,inflammation,oxidative stress and apoptosis were evaluated by HE,Masson,DHE,TUNEL apoptosis,immunofluorescence and immunohistochemical stains.Results Compared with 8-week MT1 group,the LA diameter in 12-month MT1 group increased significantly.Compared with 12-month control group,the LA diameter in 12-month MT1 group also increased significantly(P<0.05).Electrical stimulation demonstrated that the AF induction rate and duration in 12-month MT1 group were significantly increased compared with 8-week MT1 group(P<0.05).Inflammatory indicator:iNOS immunohistochemical staining showed increased iNOS expression in the atrial tissue of 12-month control,MT1 and MT2 groups compared with 8-week groups.Compared to 12-month control group,12-month MT1 and MT2 groups exhibited significantly higher iNOS expression(P<0.05).Indicators of fibrosis level:Masson staining revealed that the atrial fibrosis levels increased in 12-month control,MT1 and MT2 groups compared with 8-week groups.The 12-month MT1 and MT2 groups showed significantly higher fibrosis levels than the 12-month control group(P<0.05).TypeⅢcollagen expression increased in the 12-month control,MT1,and MT2 groups compared to the 8-week groups.The 12-month MT1 and MT2 groups had significantly higher levels than the 12-month control group(P<0

关 键 词：房颤 褪黑激素受体1A 褪黑激素受体1B 

分 类 号：R541.7[医药卫生—心血管疾病]