ABSTRACT
The effects of an intravenous bolus injection of 25 ug x 100 g (-1) b.w. of a purified toxin from the Brazilian scorpion Tityus serrulatus on the rat jejunal absorption and secretion of water, glucose, sodium and chloride were studied in a jejunal loop perfused "in situ" using polyethyleneglycol as a marker, in anesthetized animals. The results seem to indicate that only chloride transport was affected by the toxin as the data analysis have shown a statistically significant increase in the absorption of that ion, while the sodium, glucose and water values before and after toxin remained the same. The addition of toxin into an organ bath containing a segment of jejunum immersed in Tyrode's solution evoked a strong and sustained contraction followed by oscillations of tonus. These effects were resistant even to repeated washings with the bathing solution, but were partially abolished by atropine.