Andrade Tadeu U, Santos Maria Carmen S, Busato Vera Cristina W, Medeiros Ana Raquel S, Abreu Gláucia R, Moysés Margareth R, Bissoli Nazaré S
Department of Pharmacy, University Center of Villa Velha, Espírito Santo, Brazil.
Arch Med Res. 2008 Jan;39(1):27-32. doi: 10.1016/j.arcmed.2007.06.020. Epub 2007 Oct 23.
We investigated the influence of short-term treatment with supraphysiological doses of an anabolic-androgenic steroid on the Bezold-Jarisch reflex (BJR) control of heart rate (HR) and whether this treatment induced cardiac hypertrophy and anabolic effects in rats.
Male rats were treated with nandrolone decanoate (10 mg/kg(-1) body weight/4 weeks; DECA) or vehicle control (CON). After 4 weeks of treatment, BJR was evaluated by bradycardia responses that were elicited by serotonin administration (2-32 microg/kg(-1)). Mean arterial pressure (MAP) was assessed and cardiac hypertrophy was determined by the left ventricle weight/body weight (LVW/BW) ratio. Histological analyses of LV and the measurement of the total body protein content of the animals were performed.
Nandrolone decanoate (ND) treatment had no effect on the MAP (CON=105+/-5; DECA=110+/-3 mmHg). However, the mean basal HR of DECA animals was significantly lower than that of control animals (CON = 381+/-14; DECA=324+/-12 bpm; p<0.01). ND did not change the sensitivity of the BJR. The LVW/BW ratio indicated significant hypertrophy of the LV in DECA animals (CON=1.76+/-0.04; DECA=2.0+/-0.04 mg/g; p<0.01). Histological and morphometrical analyses demonstrate that there is also modest myocyte hypertrophy (CON=14.5+/-1.5; DECA=20.0 +/- 0.9 myocyte nuclei/field; p<0.05). However, the Masson-trichromic-stained samples showed an enhancement of collagen deposits on the LV matrix.
We concluded that 4 weeks ND treatment induced an anabolic effect and the beginnings of LV remodeling, mainly due to excessive collagen deposition in the cardiac extracellular matrix. However, the treatment did not influence BJR control of bradycardia, an effect that could be explained by an enhanced efferent vagal tonus in DECA animals.
我们研究了超生理剂量的合成代谢雄激素类固醇短期治疗对贝佐尔德-雅里什反射（BJR）控制心率（HR）的影响，以及这种治疗是否会在大鼠中诱导心脏肥大和合成代谢效应。
雄性大鼠接受癸酸诺龙（10mg/kg体重/4周；DECA）或载体对照（CON）治疗。治疗4周后，通过给予血清素（2 - 32μg/kg体重）引发的心动过缓反应来评估BJR。评估平均动脉压（MAP），并通过左心室重量/体重（LVW/BW）比值确定心脏肥大。对左心室进行组织学分析并测量动物的全身蛋白质含量。
癸酸诺龙（ND）治疗对MAP无影响（CON = 105±5；DECA = 110±3 mmHg）。然而，DECA动物的平均基础心率显著低于对照动物（CON = 381±14；DECA = 324±12次/分钟；p<0.01）。ND没有改变BJR的敏感性。LVW/BW比值表明DECA动物的左心室有明显肥大（CON = 1.76±0.04；DECA = 2.0±0.04mg/g；p<0.01）。组织学和形态计量学分析表明也存在适度的心肌细胞肥大（CON = 14.5±1.5；DECA = 20.0±0.9个心肌细胞核/视野；p<0.05）。然而，Masson三色染色样本显示左心室基质上的胶原沉积增加。
我们得出结论，4周的ND治疗诱导了合成代谢效应和左心室重塑的开始，主要是由于心脏细胞外基质中过多的胶原沉积。然而，该治疗并未影响BJR对心动过缓的控制，这种效应可以用DECA动物中增强的传出迷走神经张力来解释。
