Differential effects of two bile salts on ion transport characteristics of teleost intestine

1. 1. The effects of a dihydroxy and a trihydroxy bile salt on the Na⁺- and Cl^--absorbing, goby posterior intestine are quite different. 2. 2. Taurochenodeoxycholate, a dihydroxy bile salt, increases tissue permeability to Cl^-, primarily by opening the paracellular shunt pathway. 3. 3. The trihydroxy bile salt taurocholate lacks these effects and may, in fact, decrease tissue permeability. 4. 4. In light of the general structural similarity of these two molecules, a detergent action is considered unlikely and, instead, a more specific (perhaps receptor-mediated) mechanism is suggested.