title: Different effects of calcium flux-blocking agents on light and potassium stimulated release of taurine from retina.
abstract: Conditions for the stimulation of taurine release by illumination or increased K+ concentrations were established. The effect of Mg2+, ruthenium red and verapamil on taurine release induced by both procedures was compared. All these agents antagonize Ca2+-dependent release of neurotransmitters. Illumination-induced release of taurine was not blocked by any of these agents while the K+-induced release was blocked by all of them. It is discussed whether illumination and potassium act through processes that increase Ca2+ influx through different mechanisms, or if illumination-induced release is a Ca2+-independent process.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D004492:Edetic Acid / Q000494:pharmacology; D008027:Light; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D011188:Potassium / Q000008:administration & dosage / Q000378:metabolism*; D012160:Retina / Q000187:drug effects / Q000378:metabolism*; D012430:Ruthenium Red / Q000494:pharmacology; D013268:Stimulation, Chemical; D013654:Taurine / Q000378:metabolism*; D014700:Verapamil / Q000494:pharmacology
chemical_list: D012430:Ruthenium Red; D013654:Taurine; D004492:Edetic Acid; D014700:Verapamil; D008274:Magnesium; D011188:Potassium; D002118:Calcium