Influence of inorganic and organic arsenicals on intestinal transfer of nutrients.

The effects of organic (oxophenylarsine, PhAsO 2.5-50 mumol/l) and inorganic arsenicals (As2O3 2.5-250 mumol/l; As2O5 2.5-2500 mumol/l) on intestinal transfer of water, sodium, glucose and leucine was investigated in vitro using isolated jejunal segments of male Sprague Dawley rats. All three arsenicals decreased in a dose-dependent manner the transfer of water, sodium, glucose and leucine. At the highest concentrations investigated the amount absorbed was reduced to some 10-20% of the respective control values. For both glucose and leucine the concentration ratio between absorbate and perfusate was about 3.5-4 in controls. It decreased to about 2 for leucine and to near unity for glucose. As assessed from the concentration ratio between intestinal tissue and perfusate the arsenic compounds inhibited the uptake of glucose and leucine into the tissue. There was a marked difference with respect to the potency of arsenicals, PhAsO being about 10 times more potent than As2O3 which in turn was about 5 times more potent than As2O5.