Effects of Ca2+ and calmodulin antagonists on the oxygen uptake induced by acetylcholine or substance P in rat submandibular gland slices.
Effects of Ca2+ and calmodulin antagonists on the oxygen uptake induced by acetylcholine (ACh) or substance P (SP) were investigated in rat submandibular gland slices. The oxygen uptake induced by ACh or SP was significantly inhibited by removing Ca2+ from the medium and the slices. The oxygen uptake by ACh in the Ca2+-deficient slices was almost completely recovered by the addition of 3.0 and 5.0 mM Ca2+, whereas that by SP was not recovered by the addition of 3.0 mM Ca2+, but recovered by 5.0 mM Ca2+. Ca2+ antagonists, diltiazem, verapamil and La3+, significantly inhibited the ACh-induced oxygen uptake. On the other hand, the SP-induced oxygen uptake was inhibited by diltiazem and La3+, but not by verapamil. Calmodulin antagonists, trifluoperazine, chlorpromazine and W-7, had no inhibitory effects on the ACh-induced oxygen uptake. The SP-induced oxygen uptake was not affected by trifluoperazine, chlorpromazine and low concentrations of W-7, but was inhibited by high concentrations of W-7. These results suggest that the ACh- or SP-induced oxygen uptake is dependent on the presence and permeability of Ca2+ with a subtle difference between the ACh and the SP mechanisms and that the oxygen uptake is independent of calmodulin.
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002147:Calmodulin / Q000037:antagonists & inhibitors*; D002746:Chlorpromazine / Q000494:pharmacology; D004110:Diltiazem / Q000494:pharmacology; D066298:In Vitro Techniques; D007811:Lanthanum / Q000494:pharmacology; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D013363:Submandibular Gland / Q000378:metabolism*; D013373:Substance P / Q000494:pharmacology*; D013449:Sulfonamides / Q000494:pharmacology; D014268:Trifluoperazine / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
D002121:Calcium Channel Blockers; D002147:Calmodulin; D013449:Sulfonamides; D014665:Vasodilator Agents; D014268:Trifluoperazine; D013373:Substance P; C017967:W 7; D007811:Lanthanum; D014700:Verapamil; D004110:Diltiazem; D000109:Acetylcholine; D002746:Chlorpromazine