Cyclosporin A administration is associated with an increased incidence of hypertension. To evaluate the direct effects of the drug on the contractile responses of vascular tissue to adrenergic stimuli, rat caudal artery ring segments were studied before and after the addition of cyclosporin A or its ethanol vehicle in vitro. In a dose-related manner, cyclosporin A augmented the contractile resp...

Calcium (Ca(2+)) and calmodulin (CaM) are required for progression of mammalian cells from quiescence into S phase. In multiple cell types, cyclosporin A causes a G(1) cell cycle arrest, implicating the serine/threonine phosphatase calcineurin as one Ca(2+)/CaM-dependent enzyme required for G(1) transit. Here, we show, in diploid human fibroblasts, that cyclosporin A arrested cells in G(1) befo...

BACKGROUND The multidrug resistance phenomenon results from the expression of P-glycoprotein (P-gp), a drug-efflux pump. Corticosteroids are substrates for P-gp, whose function can be inhibited by cyclosporin. This study evaluates the ability of cyclosporin to modulate dexamethasone uptake in multidrug resistant cells. METHODS The K 562 cell line, which does not express P-gp and a P-gp expres...

OBJECTIVE There is increasing interest in the use of combination therapy for rheumatoid arthritis and in the possibility of combining the conventional drug approach with newer antirheumatic therapy. The present study investigates the efficacy of long-term prophylactic enzyme therapy and combination therapy with cyclosporin A in rats with collagen-induced arthritis. METHODS Rats with collagen-...

Raising cytosolic Ca2+ induces an increase in mitochondrial biogenesis in myotubes. This phenomenon mimics the adaptive responses of skeletal muscle to exercise. It has been hypothesized that increases in cytosolic Ca2+ during motor nerve activity stimulate mitochondrial biogenesis by activating calcineurin. Overexpression of constitutively active calcineurin increases expression of peroxisome ...