Mass changes of inositol(1,4,5)trisphosphate in trachealis muscle following agonist stimulation.
Agonist-stimulated changes in D-Ins(1,4,5)P3 has been examined in tracheal smooth muscle using a specific radioreceptor assay utilizing the binding of [3H] or [32P]Ins(1,4,5)P3 to a bovine adrenal cortex preparation. Carbachol produced a maximal increase in Ins(1,4,5)P3 concentration after 5 s (basal: 12.9 +/- 0.8; stimulated: 27 +/- 1.5 pmol/mg protein) with an EC50 of 6.7 +/- 0.8 microM. With longer stimulation periods Ins(1,4,5)P3 rapidly returned to basal values by 30 s. This is the first report of mass measurements of Ins(1,4,5)P3 in smooth muscle.
Chilvers
E R
ER
Department of Pharmacology and Therapeutics, University of Leicester, U.K.
Challiss
R A
RA
Barnes
P J
PJ
Nahorski
S R
SR
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D015220:Calcium Channels; D002217:Carbachol / Q000494:pharmacology; D002417:Cattle; D066298:In Vitro Techniques; D015544:Inositol 1,4,5-Trisphosphate; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates / Q000378:metabolism*; D009130:Muscle, Smooth / Q000187:drug effects / Q000378:metabolism*; D010277:Parasympathomimetics / Q000494:pharmacology*; D011956:Receptors, Cell Surface / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear; D013403:Sugar Phosphates / Q000378:metabolism*; D014132:Trachea / Q000187:drug effects / Q000378:metabolism
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates; D010277:Parasympathomimetics; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D013403:Sugar Phosphates; D001285:Atropine; D015544:Inositol 1,4,5-Trisphosphate; D002217:Carbachol