Biomaterial Database

The effect of M & B 22948 on carbachol-induced inositol trisphosphate accumulation and contraction in iris sphincter smooth muscle. 1991

R A Akhtar, and A A Abdel-Latif

Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta 30912-2100.

The effect of a cyclic GMP phosphodiesterase inhibitor, M & B 22948, on carbachol-induced phosphatidylinositol 4,5-bis-phosphate (PIP2) breakdown and phosphatidic acid labeling, 1,4,5-inositol trisphosphate (IP3) accumulation and muscle contraction was studied in bovine iris sphincter smooth muscle. Addition of carbachol (10 microM) to 32P-labeled tissue resulted in increased labeling of phosphatidic acid and hydrolysis of PIP2. In myo[3H]inositol labeled tissue, carbachol caused rapid accumulation of IP3 which reached its maximum at about 2 min. Under identical experimental conditions, carbachol initiated a rapid increase in muscle contraction (phasic component) which was followed by a slightly lower contractile response (tonic component) that lasted for several minutes. Pretreatment of the iris sphincter with M & B 22948 did not alter carbachol-stimulated PIP2 breakdown and phosphatidic acid labeling, IP3 accumulation, or phasic component of the contractile response. However, the tonic component of the contractile response was increasingly attenuated by increasing concentrations of the drug. In conclusion, the data presented demonstrate a close correlation between carbachol-induced IP3 accumulation and muscle contraction, and that M & B 22948 does not inhibit carbachol-induced responses in the iris sphincter.

UI	MeSH Term	Description	Entries
D007498	Iris	The most anterior portion of the uveal layer, separating the anterior chamber from the posterior. It consists of two layers - the stroma and the pigmented epithelium. Color of the iris depends on the amount of melanin in the stroma on reflection from the pigmented epithelium.
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009130	Muscle, Smooth	Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)	Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
D010716	Phosphatidylinositols	Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to the hexahydroxy alcohol, myo-inositol. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid, myo-inositol, and 2 moles of fatty acids.	Inositide Phospholipid,Inositol Phosphoglyceride,Inositol Phosphoglycerides,Inositol Phospholipid,Phosphoinositide,Phosphoinositides,PtdIns,Inositide Phospholipids,Inositol Phospholipids,Phosphatidyl Inositol,Phosphatidylinositol,Inositol, Phosphatidyl,Phosphoglyceride, Inositol,Phosphoglycerides, Inositol,Phospholipid, Inositide,Phospholipid, Inositol,Phospholipids, Inositide,Phospholipids, Inositol
D011688	Purinones		Oxopurines
D002217	Carbachol	A slowly hydrolyzed CHOLINERGIC AGONIST that acts at both MUSCARINIC RECEPTORS and NICOTINIC RECEPTORS.	Carbamylcholine,Carbacholine,Carbamann,Carbamoylcholine,Carbastat,Carbocholine,Carboptic,Doryl,Isopto Carbachol,Jestryl,Miostat,Carbachol, Isopto
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D015106	3',5'-Cyclic-GMP Phosphodiesterases	Enzymes that catalyze the hydrolysis of cyclic GMP to yield guanosine-5'-phosphate.	3',5'-Cyclic GMP 5'-Nucleotidohydrolase,3',5'-Cyclic GMP Phosphodiesterase,3',5'-Cyclic-GMP Phosphodiesterase,3,5-Cyclic GMP 5-Nucleotidohydrolase,3,5-Cyclic GMP Phosphodiesterase,3',5' Cyclic GMP 5' Nucleotidohydrolase,3',5' Cyclic GMP Phosphodiesterase,3',5' Cyclic GMP Phosphodiesterases,3,5 Cyclic GMP 5 Nucleotidohydrolase,3,5 Cyclic GMP Phosphodiesterase,5'-Nucleotidohydrolase, 3',5'-Cyclic GMP,5-Nucleotidohydrolase, 3,5-Cyclic GMP,GMP 5'-Nucleotidohydrolase, 3',5'-Cyclic,GMP 5-Nucleotidohydrolase, 3,5-Cyclic,GMP Phosphodiesterase, 3',5'-Cyclic,GMP Phosphodiesterase, 3,5-Cyclic,Phosphodiesterase, 3',5'-Cyclic GMP,Phosphodiesterase, 3',5'-Cyclic-GMP,Phosphodiesterase, 3,5-Cyclic GMP,Phosphodiesterases, 3',5'-Cyclic-GMP