VERAPAMIL REVERSES ABNORMAL [CA2-METABOLISM OF PMNL OF DIALYSIS PATIENTS(]I AND CARBOHYDRATE)

The basal levels of cytosolic calcium ([Ca2+]i) of polymorphonuclear l eukocytes (PMNL) are elevated in hemodialysis ((HD) patients, and this abnormality has been implicated in the dysfunction of the PMNL of the se patients. The elevated [Ca2+]i appears to be due to PTH-induced ent ry of calcium into PMNL, an action that may be prevented by calcium ch annel-blockers. We examined [Ca2+]i and carbohydrate metabolism of PMN L of normal subjects and of HD patients before, after eight to nine we eks of verapamil therapy (120 mg/day), and after eight to ten weeks of discontinuation of verapamil treatment. In HD patients, the basal lev els of [Ca2+]i of PMNL are elevated and their glucose uptake, the acti vity of total and active forms of glycogen synthetase, and glycogen co ntent are reduced compared to values in normal subjects (P < 0.01). Th ese derangements were normalized after verapamil therapy and re-emerge d after discontinuation of treatment with verapamil despite no change in blood; levels of PTH. The results indicate that the elevation in [C a2+]i of PMNL and the consequent derangements in carbohydrate metaboli sm of these cells are treatable with a calcium channel blocker. The da ta assign a valuable role for calcium channel blockers for the amelior ation of some aspects of cell dysfunction of uremia.