Intracellular mediators of Na -K pump activity in guinea pig pancreatic acinar cells

Journal Article · Tue Oct 01 04:00:00 EDT 1985 · Am. J. Physiol.; (United States)

OSTI ID:6082399

Hootman, S R; Ochs, D L; Williams, J A

The involvement of CaS and cyclic nucleotides in neurohormonal regulation of Na -K -ATPase (Na -K pump) activity in guinea pig pancreatic acinar cells was investigated. Changes in Na+-K+ pump activity elicited by secretagogues were assessed by (3H)ouabain binding and by ouabain-sensitive YWRb uptake. Carbachol (CCh) and cholecystokinin octapeptide (CCK-8) each stimulated both ouabain-sensitive 86Rb+ uptake and equilibrium binding of (TH)ouabain by approximately 60%. Secretin increased both indicators of Na+-K+ pump activity by approximately 40% as did forskolin, 8-bromo- and dibutyryl cAMP, theophylline, and isobutylmethylxanthine. Incubation of acinar cells in CaS -free HEPES-buffered Ringer (HR) with 0.5 mM EGTA reduced the stimulatory effects of CCh and CCK-8 by up to 90% but caused only a small reduction in the effects of secretin, forskolin, and cAMP analogues. In addition, CCh, CCK-8, secretin, and forskolin each stimulated ouabain-insensitive 86Rb+ uptake by acinar cells. The increase elicited by CCh and CCK-8 was greatly reduced in the absence of extracellular CaS , while that caused by the latter two agents was not substantially altered. The effects of secretagogues on free CaS levels in pancreatic acinar cells also were investigated with quin-2, a fluorescent CaS chelator. Basal intracellular CaS concentration ((CaS )i) was 161 nM in resting cells and increased to 713 and 803 nM within 15 s after addition of 100 microM CCh or 10 nM CCK-8, respectively.

• Research Organization: Univ. of California, San Francisco
• OSTI ID: 6082399
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States); ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID ANHYDRASES
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMALS
AROMATICS
ATP-ASE
AZAARENES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CALCIUM COMPOUNDS
CARBOHYDRATES
CARDIAC GLYCOSIDES
CARDIOTONICS
CARDIOVASCULAR AGENTS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DRUGS
ENDOCRINE GLANDS
ENZYME ACTIVITY
ENZYMES
GLANDS
GLYCOSIDES
GUINEA PIGS
HETEROCYCLIC COMPOUNDS
HORMONES
HYDROLASES
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
KININS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE TRANSPORT
MINUTES LIVING RADIOISOTOPES
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANS
OUABAIN
PANCREAS
PEPTIDES
PHOSPHOHYDROLASES
PHYSIOLOGY
POLYPEPTIDES
POTASSIUM COMPOUNDS
PROTEINS
PURINES
RADIOISOTOPES
RODENTS
RUBIDIUM 86
RUBIDIUM ISOTOPES
SECRETIN
SODIUM COMPOUNDS
STROPHANTHINS
THEOPHYLLINE
TRITIUM COMPOUNDS
VASODILATORS
VERTEBRATES
XANTHINES