ABSTRACT
Context: Exercise and anabolic steroids are anticipated to promote fat mass reduction and so to decrease the number of comorbidities related to excessive weight. Objective: The aim of this study was to verify the influence of aerobic exercise and the use of steroids on the accumulation of adipose tissue and on the biochemical limitations of Wistar rats nourished by a hypercaloric diet. Methods: Forty, young male Wistar rats were split into four groups: obese control (n=10), obese under treatment (n=10), obese under aerobic exercise (n=10) and obese under aerobic exercise and treatment (n=10). All animals were fed with a hypercaloric diet and animals under treatment received intramuscular testosterone. Body (weight and visceral fat) and blood (lipidogram, glucose, and liver enzymes) parameters were assessed. Results: The group treated with aerobic exercise and testosterone revealed a reduction in body weight and visceral, perirenal, retroperitoneal and epididymal fats, accompanied by the blood levels of glucose, lactate, LDL-cholesterol, HDL-cholesterol, and lactate dehydrogenase; following high-intensity physical activity. Conclusion: The results support the theory that the combination of steroids and physical activity reduces the side-effects of androgenic-anabolic hormones and conveys benefits to some constraints.
ABSTRACT
BACKGROUND: It was already evidenced decreased heart rate variability (HRV) in chronic obstructive pulmonary disease (COPD) patients at rest. OBJECTIVE: In order to insert new elements in the literature regarding this issue, we evaluated geometric index of HRV in COPD subjects. METHOD: We analyzed data from 34 volunteers, divided into two groups according to spirometric values: COPD (17 volunteers, FEV1/FVC=47.3±10.2; FEV1=50.8±15.7) and control (17 volunteers, FEV1/FVC=78.8±10.8; FEV1=100.1±14.7). For analysis of HRV indexes the volunteers remained in the supine position for 30 minutes. We analyzed the following indexes: triangular index (RRtri), triangular interpolation of RR intervals (TINN) and Poincaré plot (SD1, SD2 and SD1/SD2). Student t test for unpaired samples and Mann-Whitney test were used for data analysis. RESULTS: We observed statistically significant reductions in geometric indexes in the COPD group: RRtri (0.043±0.01 vs. 0.059±0.02; p=0.018), TINN (105.88±51.82 vs. 151.47±49.9; p=0.014), SD1 (9.76±4.66 vs. 14.55±6.04; p=0.014) and SD2 (34.86±17.02 vs. 51.51±18.38; p=0.010). SD1/SD2 (0.30±0.11 vs. 0.28±0.07; p=0.605) were not significantly different between groups. Patients with COPD presented a visual analysis of Poincaré plot of lower dispersion of RR intervals both beat to beat and the long term. CONCLUSION: Subjects with COPD present reduction of geometric indexes of HRV, indicating reduced heart rate variability.
Subject(s)
Heart Rate/physiology , Pulmonary Disease, Chronic Obstructive/physiopathology , Aged , Female , Heart Function Tests/methods , Humans , MaleABSTRACT
In this study the baroreflex sensitivity of conscious, juvenile, spontaneously hypertensive rats (SHRs) was compared. The study population consisted of 19 eight-week-old male SHRs. The baroreflex sensitivity was quantified as the derivative of the variation in heart rate (HR) and the variation of mean arterial pressure (baroreflex sensitivity = ΔHR/ΔMAP). MAP was manipulated with sodium nitroprusside (SNP) and phenylephrine (PHE), administered via an inserted cannula in the right femoral vein. The SHRs were divided into four groups: (1) low bradycardic baroreflex (LB) where the baroreflex gain (BG) was between 0 and -1 bpm/mmHg with PHE; (2) high bradycardic baroreflex (HB), where the BG was < -1 bpm/mmHg with PHE; (3) low tachycardic baroreflex (LT) where the BG was between 0 and 3 bpm/mmHg with SNP; (4) high tachycardic baroreflex (HT) where the BG was > 3 bpm/mmHg with SNP. We noted that 36.8% of the rats presented with an increased bradycardic reflex, while 27.8% demonstrated an attenuated tachycardic reflex. No significant alterations were noted regarding the basal MAP and HR. There were significant differences in the baroreflex sensitivity between SHRs in the same laboratory. One should be careful when interpreting studies employing the SHR as a research model.
