%0 Journal Article %T Ion transport systems in human labial acinar cells %+ National Institute of Dental Research [National Institute of Health] %A Paulais, M. %A Valdez, I. %A Fox, P. %A Evans, R. %A Turner, R. %< avec comité de lecture %@ 0193-1857 %J AJP - Gastrointestinal and Liver Physiology %I American Physiological Society %V 270 %N 1 %P G213-G219 %8 1996-01-01 %D 1996 %R 10.1152/ajpgi.1996.270.1.G213 %M 8772520 %Z Life Sciences [q-bio]/Human health and pathology/Tissues and Organs [q-bio.TO] %Z Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biologyJournal articles %X Human labial acini were assayed for the presence of ion transport systems associated with salivary fluid secretion using microfluorometric methods. Na(+)-K(+)-Cl- contransport and Na+/H+ exchange activities (determined by their bumetanide and amiloride sensitivities, respectively) were found at levels approximately 50% of those seen in similarly assayed rat parotid acini, but little, if any, C1-/HCO3-exchange activity was observed. Also, when human labial acini were stimulated with the muscarinic agonist carbachol, little evidence of the intracellular acidification associated with HCO3- secretion by other salivary glands was found. Na+/H+ exchange activity in human labial acini was downregulated (approximately 40%) by beta-adrenergic stimulation and upregulated (approximately threefold) by muscarinic stimulation. In contrast, beta-adrenergic stimulation produced only a marginally significant increase in Na(+)-K(+)-Cl- cotransport activity, and muscarinic stimulation was without effect. We include that basolateral Na(+)-K(+)-Cl- cotransport appears to be the dominant mechanism driving Cl- secretion and thereby fluid secretion in this tissue. %G English %L inserm-02448216 %U https://inserm.hal.science/inserm-02448216 %~ INSERM