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Anabolic steroids induce cardiac renin-angiotensin system and impair the beneficial effects of aerobic training in rats
- Source :
- American Journal of Physiology-Heart and Circulatory Physiology. 293:H3575-H3583
- Publication Year :
- 2007
- Publisher :
- American Physiological Society, 2007.
-
Abstract
- We evaluated the effects of swimming and anabolic steroids (AS) on ventricular function, collagen synthesis, and the local renin-angiotensin system in rats. Male Wistar rats were randomized into control (C), steroid (S; nandrolone decanoate; 5 mg/kg sc, 2×/wk), steroid + losartan (SL; 20 mg·kg−1·day−1), trained (T), trained + steroid (T+S), and trained + steroid + losartan (T+SL; n = 14/group) groups. Swimming was performed 5 times/wk for 10 wk. Serum testosterone increased in S and T+S. Resting heart rate was lower in T and T+S. Percent change in left ventricular (LV) weight-to-body weight ratio increased in S, T, and T+S. LV systolic pressure declined in S and T+S. LV contractility increased in T ( P < 0.05). LV relaxation increased in T ( P < 0.05). It was significantly lower in T+S compared with C. Collagen volumetric fraction (CVF) and hydroxyproline were higher in S and T+S than in C and T ( P < 0.05), and the CVF and LV hypertrophy were prevented by losartan treatment. LV-ANG I-converting enzyme activity increased (28%) in the S group (33%), and type III collagen synthesis increased (56%) in T+S but not in T group. A positive correlation existed between LV-ANG I-converting enzyme activity and collagen type III expression ( r2 = 0.88; P < 0.05, for all groups). The ANG II and angiotensin type 1a receptor expression increased in the S and T+S groups but not in T group. Supraphysiological doses of AS exacerbated the cardiac hypertrophy in exercise-trained rats. Exercise training associated with AS induces maladaptive remodeling and further deterioration in cardiac performance. Exercise training associated with AS causes loss of the beneficial effects in LV function induced by exercising. These results suggest that aerobic exercise plus AS increases cardiac collagen content associated with activation of the local renin-angiotensin system.
- Subjects :
- Male
medicine.medical_specialty
Time Factors
Anabolism
Physiology
medicine.medical_treatment
Blood Pressure
Cardiomegaly
Peptidyl-Dipeptidase A
Losartan
Receptor, Angiotensin, Type 1
Ventricular Function, Left
Steroid
Renin-Angiotensin System
Anabolic Agents
Heart Rate
Physiology (medical)
Internal medicine
Renin–angiotensin system
medicine
Animals
Nandrolone
Aerobic exercise
Testosterone
Rats, Wistar
Receptor
Beneficial effects
Swimming
Ventricular Remodeling
Ventricular function
business.industry
Angiotensin II
Myocardium
Myocardial Contraction
Rats
Hydroxyproline
Endocrinology
Gene Expression Regulation
Nandrolone Decanoate
Circulatory system
Collagen
Cardiology and Cardiovascular Medicine
business
Angiotensin II Type 1 Receptor Blockers
Subjects
Details
- ISSN :
- 15221539 and 03636135
- Volume :
- 293
- Database :
- OpenAIRE
- Journal :
- American Journal of Physiology-Heart and Circulatory Physiology
- Accession number :
- edsair.doi.dedup.....309fe9fcba8eaef6d1a061ebc13cd75e