INTERACTIONS OF GINSENG EXTRACT, GINSENG SEPARATED FRACTIONS, AND SOME TRITERPENOID SAPONINS WITH GLUCOSE TRANSPORTERS IN SHEEP ERYTHROCYTES

The effects of Panax ginseng extract, ginseng saponins, and some other triterpenoid saponins on glucose uptake were examined by using sheep erythrocytes. Initial rates of glucose transport were determined by measurements of 2-deoxy-D-glucose (2-DG) uptake. From kinetic analysis apparent K-m and V-max values of facilitated glucose transport in sheep erythrocytes were calculated as 2.3 +/- 0.08 mM and 1.4 +/- 0.05 nmol/min/10(9) cells. The results showed that ginseng extract stimulated glucose uptake in sheep erythrocytes dose-dependently. Ginseng saponins, in general, also stimulated glucose transport. The maximum effect was observed at 1 mu M of ginsenoside Rb-1 showing an increase of 24 +/- 5% above basal activity. However, ginsenoside Rg(3), chikusetsusaponin Ia, and glycyrrhetic acid induced significant inhibitory effects on glucose transport in sheep erythrocytes.