EFFECTS OF SHORT-CHAIN FATTY-ACIDS ON ELECTROPHYSIOLOGICAL PROPERTIESAND PERMEABILITY CHARACTERISTICS OF SHEEP (OVIS-ARIES) ABOMASAL MUCOSA

Transepithelial potential differences (PD), electrical conductances (G ,) and mannitol fluxes were measured in sheep abomasal epithelia incub ated in vitro with either short-chain fatty acids (SCFA) or with lacti c acid. In contrast to lactic acid a SCFA mixture, or acetic acid alon e, drastically reduced both PD and G(t) within minutes. Transepithelia l mannitol fluxes were significantly reduced by SCFA during 60 min of incubation but increased greatly during incubation over two consecutiv e flux periods of 60 min. Lactic acid had no such effect. It is sugges ted that SCFA may overload pH and volume regulative systems of the abo masal epithelial cells resulting in cell swelling and reduced transepi thelial rheogenic transport.