cholecalciferol and Cardiomegaly

Puromycin aminonucleoside-induced nephrotic syndrome (PAN-NS) is characterized by cardiac remodeling and increased local inflammatory activity. Patients with NS and animal models of NS have vitamin D3 deficiency. The aim of the present study was to evaluate the influence of calcitriol on cardiac remodeling and local inflammatory state in PAN-NS rat model. Male Sprague-Dawley rats were injected with PAN or vehicle on day 0. PAN and control rats were divided into two subgroups for the administration of calcitriol (PAN-D and Ct-D groups) or the vehicle (PAN-V and Ct-V groups) during 21 days. On day 21, the renal function, metabolic balance, calcitriol and FGF-23 plasma levels, prohypertrophy and proinflammatory markers (ET-1, TGF-

Topics: Animals; Calcitriol; Cardiomegaly; Cholecalciferol; Cytokines; Fibroblast Growth Factor-23; Humans; Male; Nephrotic Syndrome; Puromycin Aminonucleoside; Rats; Rats, Sprague-Dawley

To determine whether the changes in cardiovascular function that accompany vitamin D3 deficiency are the direct result of hypovitaminosis D3 or a response to the hypocalcemia that accompanies vitamin D3 deficiency, rats were maintained for 9 wk on a vitamin D3-deficient diet containing either low (0.4%) calcium or high (2.5%) calcium to prevent hypocalcemia. Rats were also maintained on the low-calcium, vitamin D3-deficient diet for 9 wk and then transferred to diets designed to reverse hypocalcemia or vitamin D3 deficiency. The results demonstrate that the changes in in vitro cardiac contractile function that accompany vitamin D3 deficiency 1) could not be prevented by preventing the hypocalcemia that normally accompanies vitamin D3 depletion or 2) could not be reversed by restoration of serum calcium to normal levels after the initial period of vitamin D3 depletion. In contrast, the change in in vitro vascular muscle contractile function observed in vitamin D3-deficient, hypocalcemic rats could be prevented by maintaining serum calcium at normal levels and also reversed by restoration of serum calcium to normal after an initial period of vitamin D3 deficiency. These observations indicate that hypocalcemia does not account for the changes in cardiac contractile function that result from vitamin D3 depletion and suggest a direct role for vitamin D3 or its metabolite 1,25-dihydroxyvitamin D3 in regulating cardiac contractility. Possible mechanisms underlying this direct effect were also explored.

Topics: Animals; Aorta; Calcitriol; Calcium; Cardiomegaly; Cholecalciferol; Hydroxycholecalciferols; Ions; Male; Myocardial Contraction; Nitrendipine; Phosphates; Rats; Sarcolemma; Vitamin D Deficiency