Sodium and chloride transport across the isolated rabbit ciliary body

Unidirectional Na+ and Cl- fluxes were determined in the isolated rabbit ciliary body under short-circuited conditions. A statistically significant net Cl- flux towards aqueous was detected in the standard bathing solution (HCO3- = 115 mM), but no net Na+ flux was demonstrated in this solution. The net Cl- flux exceeded the short-circuit current, suggesting the existence of a net flux of other ion(s). In a bathing solution containing 5 mM HCO3-, the net Cl- flux was abolished, suggesting that HCO3- in the bathing solution enhances the net Cl- flux.