Endurance running acutely raises plasma osteoprotegerin and lowers plasma receptor activator of nuclear factor kappa B ligand.

Abstract The balance of the 2 cytokines, osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa B ligand (soluble (s)RANKL), is known to have considerable influence on bone formation and degradation. Plasma concentrations of OPG and (s)RANKL were determined in a total of 31 long-distance runners before and immediately after running distances of either 15 or 42.195 km, respectively. In both groups of endurance runners, a significant decrease of sRANKL was observed during the run, the extent of which correlated to the running distance. Furthermore, OPG increased only in runners covering the marathon distance of 42.195 km. We hypothesize that the known positive effect of long-distance running on the skeletal mass may be mediated by the OPG/sRANKL system.

The effect of ACE inhibitor and angiotensin II blocker therapy on early posttransplant kidney graft function.

BACKGROUND: It is unknown whether continuation of angiotensin-converting enzyme (ACE) inhibitor or angiotensin II (ATII) blocker therapy after kidney transplantation has an influence on early kidney graft function. METHODS: We compared early postoperative graft function between 260 cadaveric kidney transplant recipients, either with or without peritransplantation ACE inhibitor/ATII blocker therapy. Regression analysis was used to show the influence of variables interfering with posttransplantation serum creatinine levels. The effect of different variables on the occurrence of delayed graft function (DGF) was analyzed by means of stepwise logistic regression. Improvement in kidney function during the first week after transplantation was compared between groups by means of Kaplan-Meier survival analysis. RESULTS: Intake of an ACE inhibitor or ATII blocker did not influence immediate posttransplantation graft function or the occurrence of DGF. Conversely, serum creatinine levels decreased significantly faster in patients administered an ACE inhibitor/ATII blocker than in those without therapy (P < 0.01). The only variables delaying graft function were number of previous transplantations, cold ischemia time, and male sex. Among patients with DGF, those with ACE inhibitor/ATII blocker therapy had significantly faster graft recovery (P < 0.001). CONCLUSION: Our results suggest that intake of an ACE inhibitor or ATII blocker during the immediate posttransplantation course is safe and does not impair graft function. Additionally, patients with DGF might profit from blockade of the renin-angiotensin-aldosterone system, which possibly shortens the time to graft recovery.

Increases in plasma levels of atrial and brain natriuretic peptides after running a marathon: are their effects partly counterbalanced by adrenocortical steroids?

OBJECTIVE: Long-distance running results in considerable stress. Little evidence exists about the role of the atrial and brain natriuretic peptides, ANP and BNP, deriving from the myocardium. The aim of our study was to investigate the influence of running 42.195 km on changes in circulating natriuretic propeptides and adrenocortical steroids. DESIGN AND METHODS: We studied 17 male and 2 female runners (age: 28-62 Years) participating in a marathon. Blood samples were obtained before and immediately after the competition. proANP(1-98) and proANP(1-30) as well as Nt-proBNP(8-29) were determined by enzyme immunoassays. RESULTS: Runners finished the competition between 2 h 58 min and 4 h 25 min. We observed a more pronounced increase in proANP(1-98) (+58%) and proANP(1-30) (+99%, both P<0.001) compared with Nt-proBNP(8-29) (+6%; P=0.005). Increases in proANP(1-30) positively correlated with runners' age (r=0.53; P=0.02). We also observed a marked increase in cortisol (+73%) and especially in aldosterone (+431%, both P<0.001). CONCLUSIONS: Cardiac strain during long-distance running may explain the pronounced increase in proANP. Other explanations for the observed rise in plasma levels might be a change in the permeability of myocardial cells and an impaired clearance. A rise in adrenocortical steroids may compensate for the negative influence of ANP on natriuresis and blood pressure. Positive effects of ANP during a marathon could be the regulation of body temperature by influencing sweat glands as well as the stimulation of lipolysis compensating for the enormous energy demand.

[Muscle cell proteins are selectively released into the blood stream by marathon running]. / Marathonlaufen lässt intrazelluläre Proteine aus Muskelzellen selektiv in das Plasma austreten.

In 19 marathon runners of both sexes, plasma concentrations of total creatine kinase (CK) activity, CKMB mass, myoglobin and troponin I were determined before and immediately after the race. Total CK activity and myoglobin increased significantly in all runners and showed neither a correlation with the individual age of the runners nor with the time they needed to reach the goal. In 12 of the runners, CKMB mass increased during the race to a level suggesting myocardial necrosis. However, the runners did not show any detectable deterioration of cardiac function after the race. The appearance of considerable amounts of muscle proteins in plasma precipitated by the muscle strain during the race seems explained by damage of skeletal muscle detected by histological studies. These phenomena may also be a consequence of profoundly disturbed cellular permeability, perhaps due to a kind of local stunning of muscle tissue by prolonged muscular strain.