INFLUENCE OF INORGANIC AND ORGANIC ARSENICALS ON INTESTINAL TRANSFER OF NUTRIENTS

The effects of organic (oxophenylarsine, PhAsO 2.5 - 50 mumol/l) and i norganic arsenicals (As2O3 2.5 - 250 mumol/l; As2O5 2.5 - 2500 mumol/l ) on intestinal transfer of water, sodium, glucose and leucine was inv estigated in vitro using isolated jejunal segments of male Sprague Daw ley rats. All three arsenicals decreased in a dose-dependent manner th e transfer of water, sodium, glucose and leucine. At the highest conce ntrations 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 glu cose and leucine into the tissue. There was a marked difference with r espect to the potency of arsenicals, PhAsO being about 10 times more p otent than As2O3 which in turn was about 5 times more potent than As2O 5.