GI pharmacology of polyethyleneimine I: effects on gastric emptying in rats.

Experiments were conducted to determine the effect of ingested polyethyleneimine upon gastric emptying of the fasted rat. Emptying was evaluated by the phenolsulfonphthalein and resin bead methods. The two techniques gave comparable results; both showed that this agent inhibited gastric emptying. A delay in gastric emptying could be detected within 15 min of intubation. The effect was dose related, quite long lasting (approximately 4 hr), and reversible. Commercially available, branched polyethyleneimines were highly active, but the linear polyethyleneimine was without observable effect. A branched polyethyleneimine derivative with all primary amine sites selectively acetylated also was inactive.