Effects of arachidonic acid and cyclo (his-pro) on zinc transport across small intestine and muscle tissues

Previously we have shown that arachidonic acid (AA) plus zinc or cyclo (his -pro) (CHP) plus zinc improve clinical signs of diabetes in streptozotocin- induced diabetic rats. Since streptozotocin destroys pancreatic P-cells, we hypothesize that the effect of either AA or CHP, plus zinc on glucose meta bolism is via mobilization of intracellular zinc which in turn stimulates g lucose uptake by peripheral tissues. We now report the relationship between zinc and AA and between zinc and CHP in controlling zinc influx and efflux across hindlimb muscle cells isolated from three-month old rats. Although CHP increased muscle zinc influx in a dose-dependent manner, AA was not eff ective. However, AA was more effective in stimulating zinc efflux than CHP. We have previously demonstrated that AA stimulates intestinal zinc uptake and absorption, and now present evidence that CHP also influences intestina l zinc transport. These results suggest that both AA and CHP affect glucose uptake in muscle cells via stimulating intestinal zinc absorption and musc le cell zinc flux. (C) 2001 Elsevier Science Inc. All rights reserved.