Effect of fluoride on the absorption of dietary fat in rats

The inhibition of lipid absorption by sodium fluoride in adult male rats was investigated following intraduodenal infusion of labeled lipid and cannulation of the intestinal lymphatics. A striking delay in both the appearance and total amount of lymph radioactivity was observed when 26 mM fluoride was included in the infusate. Effective inhibition of lipid absorption was observed over a 15-fold wide range of fluoride concentration (3.3-56 mM). The inhibitory effect of fluoride was not due to an inhibition of lipolysis since the absorption of free palmitic acid was inhibited to the same extent as that of tripalmitoyl glycerol. Studies on the uptake and distribution of infused lipid in the upper small intestine an experiments examining the extent of fluoride-induced absorptive inhibition of different fatty acids suggest that the effect of fluoride may be on the mucosal reesterification of dietary lipid.