Efeito da associação de Nandrolona e Metoprolol sobre o sistema muscular e reprodutivo de ratos

Abstract

CHAPTER II: The effects of the association of nandrolone with metoprolol on striated muscle were investigated. Forty male Wistar rats were randomly distributed into four groups: control, treated with nandrolone 20mg/kg/week, treated with metoprolol 1mg/kg/day, and treated with both nandrolone and metoprolol. Left ventricle, soleus, and gastrocnemius sections were cut on a cryostat (5&#956;m), and stained with hematoxylin and eosin, or picrosirius red. Digital images were captured and analyzed by software. Cross-sectional area (CSA), diameter, number of myonuclei per fiber, central myonuclei, splitting cells, myonuclear domain, percentage of non-contractile tissue, and serum testosterone were measured. Glucocorticoid (GR) and androgen receptor (AR) were analyzed by immunodetection. An increase was seen in the morphometric parameters analyzed in both cardiac and striated fibers from animal treated with nandrolone. Metoprolol partially restored the cardiac hypertrophy caused by nandrolone without reducing the final percentage of non-contractile tissue in the ventricle. However, the anabolic effect of nandrolone was not reestablished by metoprolol in the striated fiber. Nandrolone administration increased serum testosterone levels and up-regulated the expression of AR whereas down-regulated the expression of GR (P<0.05). Our results suggest that the effects of the association of nandrolone with metoprolol are different in cardiac and muscle fibers. CHAPTER III: The effects of the association of nandrolone and metoprolol on the reproductive system, serum testosterone, total protein, and glutamate and glutamine concentrations of rats were investigated. Forty male Wistar rats were randomly distributed into 4 groups: control, treated with metoprolol 1mg/kg/day, treated with nandrolone 20mg/kg/week, and treated with both metoprolol and nandrolone. Testes and spermatozoa were histologically processed and analyzed to determine: volume, mass, size, width of the seminiferous tubules, epithelial height, tubular lumen, and volumetric proportion. Head images from spermatozoa were captured and analyzed by software to assess the difference between coloration and structure. Nandrolone treatment caused a decrease in mass, diameter and testicular size, as well as width of the seminiferous tubules, epithelial height, tubular lumen and volumetric proportion. On the other hand, serum testosterone, total protein and glutamine and glutamate concentrations were higher in these animals (P<0.05). Metoprolol did not cause any significant effect on the morphological parameters investigated. The alterations caused by nandrolone were significantly lower when analyzed in association with metoprolol, which could indicate a possible protective effect of the beta-blocker on the testes.