| Objective To establish the rat model of heart failure using adriamycin-induced dilated cardiomyopathy (Adr-DCM), and to compare the effects of human recombinant growth hormone (hr-GH) alone and hr-GH added coenzyme Q10 (Co Q10).Methods Fifty male Wistar rats were randomly divided into four groups: normal control group, Adr control group, hr-GH group, and hr-GH added Co Q10 group. The rats in the latter three groups were treated with adriamycin (2.5mg/kg body weight per day, ip) for 4 weeks. The rats in normal control group received an equal volume of normal saline for six weeks. After 4 weeks, left ventricular dimension and cardiac function were studied by echocardiogram in all animals. Then, the rats in Adr control group, hr-GH group, and hr-GH added Co Q10 group received an equal volume of normal saline alone, hr-GH (0.5mg/kg per day, ip), and hr-GH (0.5mg/kg per day, ip) added Co Q10 (30mg/kg per day, with stomach-tube) for two weeks, respectively. After 6 weeks, left ventricular dimension and cardiac function in all rats were detected by echocardiogram. Right atrial pressure and right ventricular pressure were measured by invasive catheter, and the changes of hemodynamics were recorded by physiological signal recording instrument. Left ventricular interior diameter and the thickness of left ventricular free wall were measured after all rats were killed. Myocardial collagen network remodeling was observed by Van Gieson stain and collagen volume fraction (CVF) was calculated by pathological imagine analysis system.Results (1)After finish of the experiment, the number of rats in normal control group, Adr control group, hr-GH group, and hr-GH added Co Q10 group is 12, 9, 8 and 9, respectively; (2)Left ventricular end-diastolic diameter (LVED) and left ventricular end-systolic diameter (LVES) in Adr control group were significant larger than those in normal control group (7.00±0.50 vs. 6.50±0.33 mm, P<0.01 and 4.60±0.34 vs. 3.40±0.42 mm, P<0.01; respectively). Left ventricular end-diastolic pressure (LVEDP), right ventricular pressure (RVP), Left ventricular interior diameter, and collagen volume fraction (CVF) in Adr control group were also significant higher than those in normal control group (10.8±2.3 vs. 1.4±0.4 mmHg, P<0.01; 24.7±5.1 vs. 19.2±4.5 mmHg, P<0.01; 3.54±0.39 vs. 2.91±0.2 mm, P<0.01; and 18.26%±3.93% vs. 12.06%±3.86%, P<0.01; respectively). On the contrary, the left ventricular ejection fraction (LVEF), the fraction shortening (FS), left ventricular systolic maximum pressure (LVSP), the maximum rate of ventricular pressure rise (+dp/dtmax) and fall (-dp/dtmax) in Adr control group were significant lower than those in normal control group (65.61%±3.75% vs. 82.56±6.4%, P<0.01; 33.86%±3.04% vs. 47.39%±4.96%, P<0.01; 78.7±8.3 vs. 119±10.5 mmHg, P<0.01; 1038±618 vs. 5185±840 mmHg/s, P<0.01; and 934±494 vs. 3817±506 mmHg/s, P<0.01; respectively). The thickness of left ventricular retral wall in end-diastolic and the thickness of left ventricular free wall in Adr control group were also significant less than those in normal control group (1.44±0.15 vs. 1.74±0.33 mm, P<0.01 and 2.65±0.31 vs. 3.07±0.27 mm, P<0.01; respectively). But there is no significant difference of right atrial pressure between two groups (P>0.05). The LVEF and FS at six weeks in Adr control group were lower than those at four weeks (P<0.05). Cardiac myocyte hypertrophy accompanied with nucleus augmentation, differentiation and defferiation. There were spot lysis, granular degeneration and vacuolation in the myocytic plasm. The intercellular space became enlargement. Those were observed in the rat myocardium in all samples in Adr control group, but not occurred in the normal control group. As compared with normal control group, the quantity of myocardium interstitial collagen fibers and CVF were increased significantly in Adr control group (18.26%±3.93% vs. 12.06%±3.86%, P<0.01), but there were no differences among the three subgroups (P>0.05). (3) The LVES, LVEDP, and CVF in hr-GH group were sign...
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