We aimed to identify sex differences in the network properties and to recognize the geometric alteration effects of long-term swim training in a rat model of exercise-induced left ventricular (LV) hypertrophy. Thirty-eight Wistar rats were divided into four groups: male sedentary, female sedentary, male exercised and female exercised. After training sessions, LV morphology and function were checked by echocardiography. The geometry of the left coronary artery system was analysed on pressure-perfused, microsurgically prepared resistance artery networks using in situ video microscopy. All segments over > 80 μm in diameter were studied using divided 50-μm-long cylindrical ring units of the networks. Oxidative-nitrative (O-N) stress markers, adenosine A2A and estrogen receptor (ER) were investigated by immunohistochemistry. The LV mass index, ejection fraction and fractional shortening significantly increased in exercised animals. We found substantial sex differences in the coronary network in the control groups and in the swim-trained animals. Ring frequency spectra were significantly different between male and female animals in both the sedentary and trained groups. The thickness of the wall was higher in males as a result of training. There were elevations in the populations of 200- and 400-μm vessel units in males; the thinner ones developed farther and the thicker ones closer to the orifice. In females, a new population of 200- to 250-μm vessels appeared unusually close to the orifice. Physical activity and LV hypertrophy were accompanied by a remodelling of coronary resistance artery network geometry that was different in both sexes.

中文翻译：

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通过原位视频显微技术对游泳训练大鼠左冠状动脉前降支进行网络分析

我们的目的是确定网络特性的性别差异，并识别运动引起的左心室（LV）肥大大鼠模型中长期游泳训练的几何改变效应。将 38 只 Wistar 大鼠分为四组：雄性久坐组、雌性久坐组、雄性运动组和雌性运动组。训练结束后，通过超声心动图检查左心室形态和功能。使用原位视频显微镜在压力灌注、显微手术制备的阻力动脉网络上分析左冠状动脉系统的几何形状。使用划分的 50 μm 长的网络圆柱环单元研究了所有直径超过 80 μm 的段。通过免疫组织化学研究氧化硝化 (ON) 应激标记物、腺苷 A2A 和雌激素受体 (ER)。运动动物的左心室质量指数、射血分数和缩短分数显着增加。我们发现对照组和接受游泳训练的动物的冠状动脉网络存在显着的性别差异。在久坐组和训练组中，雄性和雌性动物的环频谱均存在显着差异。由于训练的结果，男性的壁厚度更高。男性中 200 微米和 400 微米血管单位的数量有所增加；较细的发育得更远，较厚的则靠近孔口。在雌性中，200 至 250 微米的新血管群异常地靠近孔口。体力活动和左心室肥厚伴随着冠状动脉阻力动脉网络几何形状的重塑，这种重塑在两性中是不同的。