自发性高血压大鼠心肌半乳糖凝集素3与胶原纤维及左心功能的关系

Relationship between myocardial galectin-3 and myocardial collagen deposition,left ventricular function in aging spontaneously hypertensive rats

目的观察自发性高血压大鼠(SHR)心肌间质半乳糖凝集素3(galectin-3)的分布特点及其与胶原沉积及左心功能的关系,探讨其在SHR左心功能不全发展中的变化及意义。方法购进90只12周龄SHR及50只WKY大鼠饲养,在14~22、24~36、45~66、75~102周等4个周龄段应用超声心动图观察左心室心肌应变,免疫组化观察心肌间质galectin-3、胶原容积分数(CVF)及血管周围胶原面积(PVCA)。结果 Galectin-3与胶原纤维在SHR中均随增龄而增加,45周后高于同周龄WKY组(P<0.05),75周后最为显著(P<0.05)。Galectin-3与CVF显著正相关(r=0.70~0.80,均P<0.01),与左心室心肌各向应变呈负相关(r=-0.43^-0.56,均P<0.01),与左心室射血分数(LVEF)呈负相关(r=-0.62,P<0.01)。结论 SHR心肌间质galectin-3表达在45周龄后出现病理性增加,且与心肌纤维化的发生及左心室多维应变受损的发生次序及后期的整体功能障碍相关联,其早期阶段的变化可能与舒张功能不全密切相关,75周后导致射血分数的下降与心功能恶化。

Objective To investigate the association between myocardial galectin-3 and myocardial collagen deposition, left ventricular（LV） function in spontaneously hypertensive rats （SHR） during the development of LV dysfunction. Methods Ninety SHR and 50 WKY rats at 12 weeks old were used for experiments. During the age periods of 14-22, 24-36, 45-66 and 75-102 weeks,left ventricular ejection fraction（LVEF） and 2D strain including LV longitudinal, radial and circumferential strain（SL, SR, SC） were measured echocardiagraphically; and myocardial galectin-3, collagen volume fraction（CVF） and perivascular collagen area（PVCA） were evaluated histologically. Results Myocardial galectin-3 in SHR increased along with collagen deposition with aging, and was higher in SHR than WKY rats after 45 weeks old, aggravated significantly in the group of 75-102 weeks. Myocardial galectin-3 positively correlated to myocardial collagen （r value 0.70 to 0.80, all P〈0.01）, while negatively to all directions of systolic strain （r value -0.43 to -0.56, all P%0.01） and LVEF （r=-0.62, P〈0.01）. Conclusion Progressively increased myocardial galectin 3 occurred beginning from the week of 45 and later in SHR, along with increased collagen deposition and decreased LV multidimensional strain and LVEF, which indicates that it correlates with LV diastolic dysfunction in the early stage and in the development of systolic dysfunction after the week of 75.