Calcium mediated neurohumoral inhibition of chicken enterocyte Na influx: Role of phosphatidylinositol metabolites

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Life Sciences; (USA)

DOI:https://doi.org/10.1016/0024-3205(90)90506-M· OSTI ID:6699430

Chang, E B; Musch, M W ^[1]

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1. Univ. of Chicago, IL (USA)

Carbachol (CCH), serotonin (5HT), divalent ionophore A23187, cAMP, and certain neuropeptides, i.e. substance P (SP), inhibit the initial rate of uptake (influx) of {sup 22}Na into isolated chicken villus enterocytes. All these agents also increase cytosolic Ca. However, the increases stimulated by CCH, 5HT, and cAMP are not blocked by chelation of extracellular Ca, whereas those of A23187 and SP are. Only CCH and 5HT stimulate hydrolysis of membrane phosphoinositides to form inositol phosphates. CCH and 5HT also stimulate incorporation of ({sup 32}P)-PO{sub 4} into membrane polyphosphoinositides. These studies suggest that at least three mechanisms exist to increase cytosolic Ca in chicken enterocytes and thereby inhibit Na influx. Certain neurohumoral agents such as SP open a plasma membrane permeability for Ca, permitting extracellular Ca to enter the cell down its electrochemical gradient. These agents do not stimulate phosphadidylinositol breakdown. CCH and 5HT stimulate phosphatidylinositol breakdown and via the formation of inositol trisphosphate release Ca from intracellular stores. A third mechanism exists for cAMP which mobilizes Ca from intracellular stores, but does not involve the metabolism of membrane phosphatidylinositols.

• OSTI ID: 6699430
• Journal Information: Life Sciences; (USA), Journal Name: Life Sciences; (USA) Vol. 46:26; ISSN 0024-3205; ISSN LIFSA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALI METAL COMPOUNDS
ALKALINE EARTH METALS
AMINES
AMP
ANIMAL CELLS
ANIMALS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
AZAARENES
AZOLES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIRDS
CALCIUM
CELL CONSTITUENTS
CELL MEMBRANES
CHICKENS
DAYS LIVING RADIOISOTOPES
DRUGS
ELEMENTS
ESTERS
FOWL
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
INDOLES
INHIBITION
ION EXCHANGE
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
LIPIDS
MEMBRANE TRANSPORT
MEMBRANES
METABOLISM
METABOLITES
METALS
NEUROREGULATORS
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PARASYMPATHOMIMETICS
PEPTIDES
PERMEABILITY
PHOSPHOLIPIDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PROTEINS
PYRROLES
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
REACTION KINETICS
SEROTONIN
SODIUM COMPOUNDS
SYMPATHOMIMETICS
TRACER TECHNIQUES
TRYPTAMINES
VERTEBRATES