Ethanol effects on intestinal functions in Giardia lamblia-infected rats

The effect of Giardia lamblia infection on D-glucose uptake and brush-borde r enzymes was studied in chronically ethanol-fed rats. Giardia lamblia trop hozoites counts were significantly lower in the intestine of ethanol-fed ra ts than in the controls. Also, the Nat-dependent uptake of D-glucose and br ush-border enzymes was significantly reduced (p < 0.0001, p < 0.01, respect ively) in the G. lamblia-infected rat intestine. There was no change in Nai -independent glucose uptake under these conditions. Levels of mRNA encoding Na+-dependent D-glucose transporter (SGLT1) and brush-border sucrase and l actase were reduced in G. lamblia-infected animals compared with those of t he controls. However, the mRNA levels encoding these proteins in ethanol-fe d and control animals were similar in rat intestine. These findings suggest that downregulation of SGLT1 and disaccharidases could be responsible for the observed D-glucose malabsorption and decrease in the activity of disacc haridases in G, lamblia infection.