Effect of K+ channel-blockers on sugar uptake by isolated chicken enterocytes

✍ Scribed by M. C. Montero; M. L. Calonge; J. Bolufer; A. Ilundáin

• Book ID: 102883392
• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 567 KB
• Volume: 142
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1041420312

✦ Synopsis

The effects of Ba2+, quinine, verapamil, and CaLifree saline solutions on sugar active transport have been investigated in isolated chicken enterocytes. Ba' +, quinine, and verapamil, which have been 5hown to inhibit &'+-activated K + channels, decreased basal and theophylline-dependent 3-0-methylglucose (3-0-MG) accumulation. CaL+-free conditions reduced 3-0-MG uptake in theophylline-treated enterocytes, but it had no effect in control cells. O n the other hand, the uptake of a non-actively transported sugar, 2-deoxyglucose @DOG), by control or theophylline-treated cells wa5 not modified by the presence of verapamil or by Ca' +-removal. 3-0-MG increased ouabain-sensitive Na+-efflux, hut had no effect on either K + efflux or K + uptake. However, in the presence of Ba'+, K' uptake wa5 stimulated by 3-0-MG, and this increase was prevented by ouabain. All these findings are discussed in terms of the role that K + permeability may play in cellular homeostasis during sugar active transport.