Homologous desensitization to prostaglandins in rabbit ileum

Journal Article · Thu Jan 01 04:00:00 EST 1987 · Am. J. Physiol.; (United States)

OSTI ID:6352355

Musch, M W; Field, M; Miller, R J; Stoff, J S

Prostaglandins (PG's) increase short-circuit current (I/sub sc/), inhibit NaCl absorption, and stimulate Cl secretion in rabbit ileum. These changes occur with the following PGs; E/sub 3/, E/sub 1/, nitrilo-I/sub 2/ and, to a lesser extent, with A/sub 2/, D/sub 2/, and F/sub 2..cap alpha../. Arachidonic acid (AA) also stimulates secretion. The PG- or AA-stimulated I/sub sc/ does not persist, however, and on prolonged exposure tachyphylaxis develops. Resensitization of the I/sub sc/ response to PGE/sub 2/ is rapid, being essentially complete in 15 min after the PG is removed. Desensitization to AA is not reflected by diminished PG generation. PGE/sub 2/ release from the mucosa after AA addition is constant, although the AA-stimulated I/sub sc/ decreases. I/sub sc/ measurements indicate that PGE/sub 2/ at slightly below its EC/sub 50/ partially desensitizes and a near-maximal concentration completely desensitizes to PGE/sub 2/ but does not, however, inhibit the subsequent change in I/sub sc/ caused by theophylline or vasoactive intestinal peptide (VIP). Adenosine 3',5'-cyclic monophosphate (cAMP) measurements suggest that desensitization applies to cAMP production. PGE/sub 2/ (10/sup -5/ M) increases mucosal cAMP three- to sevenfold, but this elevation is transient; a second challenge dose, which fails to elicit a I/sub sc/ change, also fails to increase mucosal cAMP. Adenylate cyclase measurements from untreated and PGE/sub 2/-treated enterocytes demonstrate a decrease in stimulation by PGE/sub 2/ but not in stimulation by VIP, fluoride, or 5-guanylylimidodiphosphate.

• Research Organization: Columbia Univ., New York, NY
• OSTI ID: 6352355
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 252:1; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ABSORPTION
ALKALI METAL COMPOUNDS
AMP
ANIMALS
ARACHIDONIC ACID
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CARBOXYLIC ACIDS
CHLORIDES
CHLORINE 36
CHLORINE COMPOUNDS
CHLORINE ISOTOPES
CYCLASES
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DOSE-RESPONSE RELATIONSHIPS
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
GASTROINTESTINAL TRACT
HALIDES
HALOGEN COMPOUNDS
IMMUNOASSAY
IMMUNOLOGY
INTERMEDIATE MASS NUCLEI
INTESTINAL ABSORPTION
INTESTINES
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
LYASES
MAMMALS
MONOCARBOXYLIC ACIDS
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROSTAGLANDINS
RABBITS
RADIOASSAY
RADIOIMMUNOASSAY
RADIOIMMUNOLOGY
RADIOISOTOPES
SMALL INTESTINE
SODIUM CHLORIDES
SODIUM COMPOUNDS
TIME DEPENDENCE
TRACER TECHNIQUES
UPTAKE
VERTEBRATES
YEARS LIVING RADIOISOTOPES