Rivero J L, Serrano A L, Henckel P
Department of Comparative Anatomy and Pathological Anatomy, Faculty of Veterinary Science, University of Cordoba, Spain.
Vet Rec. 1995 Aug 19;137(8):187-92. doi: 10.1136/vr.137.8.187.
Biopsies of the gluteus medius muscle were taken at three different depths from 36 endurance horses aged 8.42 +/- 2.85 years and of both sexes. Twenty of the horses were considered to be excellent performers on the basis of the mean speed of their three fastest records in endurance events over the previous two or three years, whereas 16 were moderate performers. The biopsy samples were analysed for the activities of the enzymes citrate synthase (an indicator of citric acid cycle activity), 3-OH-acyl-CoA-dehydrogenase (an indicator of lipid oxidation) and lactate dehydrogenase (an indicator of anaerobic metabolism). The 20 excellent performers had higher activities of citrate synthase (P < 0.001) and 3-OH-acyl-CoA-dehydrogenase (P < 0.02) than the 16 moderate performers. The activities of citrate synthase and 3-OH-acyl-CoA-dehydrogenase increased by 65 per cent and 75 per cent, respectively, and the activity of lactate dehydrogenase decreased by 23 per cent in the samples taken at successively greater depths. There was a strong linear relationship between the ratios of the activities of lactate dehydrogenase/citrate synthase and lactate dehydrogenase/3-OH-acyl-CoA-dehydrogenase and the depth from which the samples were taken for both performance groups (P < 0.001). The intercepts of the regression lines were higher in the moderate than in the excellent performers (P < 0.001 and P < 0.01 for the two ratios), showing that the endurance horses with the better performance record had a greater aerobic capacity and a relatively lower anaerobic capacity in the gluteus medius muscle than the horses with a poorer record.
对36匹年龄为8.42±2.85岁、雌雄皆有的耐力赛马，在臀中肌的三个不同深度进行活检。根据前两到三年耐力赛中三次最快记录的平均速度，其中20匹马被认为是优秀选手，而另外16匹是中等水平选手。对活检样本分析了柠檬酸合酶（柠檬酸循环活性指标）、3-羟基酰基辅酶A脱氢酶（脂质氧化指标）和乳酸脱氢酶（无氧代谢指标）的活性。20匹优秀选手的柠檬酸合酶活性（P<0.001）和3-羟基酰基辅酶A脱氢酶活性（P<0.02）高于16匹中等水平选手。在依次更深的取样深度，柠檬酸合酶和3-羟基酰基辅酶A脱氢酶的活性分别增加了65%和75%，而乳酸脱氢酶的活性下降了23%。对于两个表现组，乳酸脱氢酶/柠檬酸合酶和乳酸脱氢酶/3-羟基酰基辅酶A脱氢酶活性比值与取样深度之间存在很强的线性关系（P<0.001）。中等水平选手的回归线截距高于优秀选手（两个比值分别为P<0.001和P<0.01），表明与记录较差的马相比，表现记录较好的耐力赛马臀中肌的有氧能力更强，无氧能力相对较低。
