title: The effects of glibenclamide and its non-sulfonylurea analogue HB 699 on the sodium content of rat pancreatic islets.
abstract: Sodium contents were determined in rat pancreatic islets using integrating flame photometry. Whereas the sodium content decreased in the presence of glucose, it increased when 0.1-100 mumol/l glibenclamide was added to a medium containing 3 mmol/l glucose. The complexity of the glibenclamide action became evident with its reversal after removal of extracellular Ca2+ and the observation that the sulfonylurea counteracted the increase of sodium obtained after removal of K+. The effects of glibenclamide were mimicked by 1 mmol/l of its non-sulfonylurea analogue HB 699 with the exception that the latter compound being without suppressive action on the sodium content in medium deprived of Ca2+. Also exposure to 1 mmol/l sulfadiazine resulted in a Ca2+-dependent increase of sodium. The results suggest a role for sodium in amplifying the secretory response to the increased entry of Ca2+ obtained with the depolarisation of the beta-cells with glibenclamide or HB 699.
authors.affiliation: Department of Medical Cell Biology, University of Uppsala, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Ali
authors.forename: N
authors.initials: N
authors.lastname: Wesslén
authors.forename: B
authors.initials: B
authors.lastname: Hellman
mesh_terms: D000818:Animals; D001549:Benzamides / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D005905:Glyburide / Q000031:analogs & derivatives / Q000494:pharmacology*; D007515:Islets of Langerhans / Q000032:analysis* / Q000378:metabolism; D008297:Male; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000032:analysis* / Q000378:metabolism
chemical_list: D001549:Benzamides; C030516:meglitinide; D012964:Sodium; D011188:Potassium; D005905:Glyburide; D002118:Calcium