[An in-vitro study of the sources of intracellular calcium in Ach-induced contractions and electrical depolarization and of the capacity of calcium antagonists to influence them in the canine detrusor].
An "in vitro" experimental line was designed to study the dependence of the canine detrussor's contractile activity on extracellular calcium, or whether on the contrary there are intracellular sources of this element. If dependence from extracellular calcium could be demonstrated, the capacity of calcium channel blockers to block the input the this ion would be studied. The conclusions arrived at were: 1. Ach- and KCl-induced activity is dependent from extracellular calcium. 2. This activity is also sensitive to the action of calcium channel blockers. 3. Calcium channel blockers block Ach-activated calcium channels completely, but only partially dose activated by KCl. 4. While the activity induced by Ach and resistant to action from calcium channel blockers is probably due to calcium released from the intracellular reservoirs, the activity induced by KCl and resistant to the calcium channel blockers action can be better explained by the activation of the transmembrane channels which cannot be blocked by this agents.
Server Pastor
G
G
Servicio de Urología, Unidad de investigación, Hospital La Fe, Valencia.
Ruiz Cerdá
J L
JL
Osca García
J M
JM
Salom Sanvalero
J
J
Jiménez Cruz
J F
JF
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004285:Dogs; D004594:Electrophysiology; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects* / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D013223:Statistics as Topic; D001743:Urinary Bladder / Q000187:drug effects* / Q000502:physiology
D002121:Calcium Channel Blockers; D000109:Acetylcholine; D002118:Calcium
Estudio "in vitro" de las fuentes del calcio intracelular en las contracciones inducidas por Ach y despolarización eléctrica y de la capacidad de los calcionantagonistas para influir sobre éstas, en detrusor canino.