In patients with chronic renal insufficiency who were undergoing cardiac angiography, endothelin receptor antagonism with SB 209670 and intravenous hydration exacerbate radiocontrast nephrotoxicity compared with hydration alone.

The influence of KCI concentration on the contraction kinetics of skinned frog muscle fibers at 5-7°C was studied at various calcium levels. The magnitude of the calcium-activated force decreased continuously as the KCI concentration of the bathing solution was increased from 0 to 280 mM. The shortening velocity at a given relative load was unaffected by the level of calcium activation at 140 mM KCI, as has been previously reported by Podolsky and Teichholz (1970. J. Physiol. [Lond.]. 211: 19), and was independent of ionic strength when the KCI concentration was increased from 140 to 280 mM. In contrast, the shortening velocity decreased as the KCI concentration was reduced below 140 mM; the decrease in velocity was enhanced when the fibers were only partially activated. In the low KCI range, the resting tension of the fibers increased after the first contraction cycle. The results suggest that in fibers activated at low ionic strength some of the cross bridges that are formed are abnormal in the sense that they retard shortening and persist in relaxing solution.

Enalaprilat augments both arterial and cardiopulmonary baroreflex control of sympathetic activity in heart failure. These augmented inhibitory influences are associated with a reduction in sympathetic outflow and may contribute to the beneficial effects of angiotensin-converting enzyme inhibitors in heart failure.

No abstract