EFFECTS OF ANTIBIOTICS ON EPITHELIAL ION-TRANSPORT IN THE RABBIT DISTAL COLON IN-VITRO

One side-effect of the therapeutic use of antimicrobial agents is resp iratory paralysis as a result of inhibition of skeletal neuromuscular transmission; cholinergic neuro-effector motor transmission in the gas trointestinal tract is inhibited by the same classes of antimicrobial agent. Study of the effects of several classes of antibiotic compound on intestinal motility has suggested that antibiotic-induced alteratio ns of intestinal motility may be related to the onset of diarrhoea or the development of antibiotic-associated colitis. These compounds may, however, also initiate or exacerbate diarrhoea by altering control of epithelial function, a possibility that has not previously been rigor ously investigated. This series of experiments investigated the effect of six antibiotics on rabbit distal colonic epithelial ion transport. Of all the antibiotics studied, only ampicillin was without effect. C lindamycin, erythromycin, gentamicin and lincomycin, each reduced the response of the epithelium to electrical field stimulation. In additio n, the lincosamides clindamycin and lincomycin reduced basal short cir cuit current and the epithelial response to acetylcholine. Vancomycin had no effect on the response to electrical field stimulation or acety lcholine but enhanced the secretory action of prostaglandin E(2). Thes e data suggest that, in addition to their ability to alter intestinal motility, a number of potential antibiotic interactions with the epith elium and its innervation may contribute to the pathogenesis of antibi otic-associated diarrhoea and colitis.