Effects of acetylcholine (ACh) and norepinephrine (NE) on phosphatidylinositol 4,5-bisphosphate (PIP/sub 2/) turnover in rabbit cornea

Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:7246716

Akhtar, R A; Abdel-Latif, A A

Muscarinic cholinergic and ..cap alpha../sub 1/-adrenergic agonists provoke hydrolysis of PIP/sub 2/ into diacylglycerol (DG) and inositol trisphosphate (IP/sub 3/) in a wide variety of tissue. Recently, IP/sub 3/ has been shown to mobilize Ca/sup 2 +/ from ER in several permeabilized tissue preparations. Although rabbit cornea is enriched in ACh and NE, the physiological function of these neurotransmitters is unclear. The present studies were initiated to determine the effects of cholinergic and adrenergic agonists on PIP/sub 2/ turnover in the cornea. Addition of ACh or NE (50 ..mu..M each) to the /sup 32/P-labeled corneas for 10 min decreased the radioactivity in PIP/sub 2/ by 33 and 36%, and increased the radioactivity in phosphatidic acid by 72 and 52%, respectively. When the corneas were labeled with myo-(/sup 3/H)inositol, ACh and NE increased the accumulation of IP/sub 3/ by 92 and 48%, respectively. The effects of ACh and NE on phospholipid labeling and IP/sub 3/ accumulation were specifically inhibited by atropine (10 ..mu..M) and prazosin (10 ..mu..M), respectively. The data suggest the presence of muscarinic cholinergic and ..cap alpha../sub 1/-adrenergic receptors in the rabbit cornea. Furthermore, activation of these receptors leads to cleavage of PIP/sub 2/ into DG and IP/sub 3/ which may function as second messengers in this tissue.

• Research Organization: Medical College of Georgia, Augusta
• OSTI ID: 7246716
• Report Number(s): CONF-8606151-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:6; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
ADRENAL HORMONES
AMINES
AMMONIUM COMPOUNDS
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
BODY AREAS
CARBOHYDRATES
CARDIOTONICS
CARDIOVASCULAR AGENTS
CLEAVAGE
CORNEA
CRYSTAL STRUCTURE
DAYS LIVING RADIOISOTOPES
DRUGS
ESTERS
EYES
FACE
HEAD
HORMONES
INOSITOL
INOSITOLS
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LIGHT NUCLEI
LIPIDS
MAMMALS
MEMBRANE PROTEINS
MICROSTRUCTURE
MONOSACCHARIDES
NEUROREGULATORS
NORADRENALINE
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANS
PARASYMPATHOMIMETICS
PHOSPHOLIPIDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PROTEINS
QUATERNARY COMPOUNDS
RABBITS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
SACCHARIDES
SENSE ORGANS
STEROID HORMONES
SYMPATHOMIMETICS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES