These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effects of K+ channel blockers and K+ ionophore on isoprenaline-induced secretion of amylase from rat parotid acini.
    Author: Murayama T, Miwa Y, Maeda S, Morisaki I, Saito K.
    Journal: Eur J Pharmacol; 1997 Mar 12; 322(1):21-5. PubMed ID: 9088865.
    Abstract:
    The involvement of K+ channels in regulating secretion of amylase from isolated rat parotid acini was studied in conjunction with beta-adrenoceptor function. It was observed that increasing the concentration of extracellular K- or adding K+ channel blockers enhanced the secretion of amylase. Among several K+ channel blockers, tetraethylammonium, apamin and charybdotoxin were effective to enhance secretion by 48, 69 and 84%, respectively. Glibenclamide was without effect. A low concentration of isoprenaline (10(-7) M) enhanced secretion by 154% and its simultaneous application with tetraethylammonium gave a synergistic effect, producing 371% stimulation. Combination of tetraethylammonium and a low concentration of carbachol (10(-6) M) did not give the synergistic effect. Isoprenaline at the concentration of 10(-6) M enhanced secretion by 313% and this was reduced to 116% by 10(-5) M valinomycin, a K+ ionophore. Valinomycin was without effect on carbachol (10(-5) M)-induced secretion. Somatostatin (10(-5) M) and morphine (10(-4) M) also reduced isoprenaline-induced secretion of amylase. These results suggested the regulation of Ca(2+)-activated K+ channels by isoprenaline in amylase secretory processes in parotid acini.
    [Abstract] [Full Text] [Related] [New Search]