Poly(A)+ RNA isolated from rat jejunum was injected into Xenopus laevis oocytes and expression of Cl−/HCO3− antiport was investigated by means of 36Cl− uptake. Two days after injection of 50 ng of poly(A)+ RNA, Cl− uptake was significantly increased with respect to water-injected oocytes. The expressed transport was inhibited by 0·2 mM DIDS, whereas endogenous Cl− uptake was unaffected by this disulphonic stilbene. After sucrose density gradient fractionation, the highest expression of DIDS-sensitive Cl− uptake was detected with mRNA size fraction of about 2–4 kb in length. The expressed Cl− uptake can occur against a Cl− concentration gradient and is unaffected by the known Cl− channel blocker anthracene-9-carboxylic acid. Cl− transport mechanism has properties similar to jejunal basolateral Cl−/HCO3− exchange with regard to Na+ dependence
Functional expression of basolateral Cl-/HCO3- exchange from rat jejunum in Xenopus laevis oocytes
GASTALDI, GIULIA;
1998-01-01
Abstract
Poly(A)+ RNA isolated from rat jejunum was injected into Xenopus laevis oocytes and expression of Cl−/HCO3− antiport was investigated by means of 36Cl− uptake. Two days after injection of 50 ng of poly(A)+ RNA, Cl− uptake was significantly increased with respect to water-injected oocytes. The expressed transport was inhibited by 0·2 mM DIDS, whereas endogenous Cl− uptake was unaffected by this disulphonic stilbene. After sucrose density gradient fractionation, the highest expression of DIDS-sensitive Cl− uptake was detected with mRNA size fraction of about 2–4 kb in length. The expressed Cl− uptake can occur against a Cl− concentration gradient and is unaffected by the known Cl− channel blocker anthracene-9-carboxylic acid. Cl− transport mechanism has properties similar to jejunal basolateral Cl−/HCO3− exchange with regard to Na+ dependenceI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.