title: Spatial localization of the stimulus-induced rise in cytosolic Ca2+ in bovine adrenal chromaffin cells. Distinct nicotinic and muscarinic patterns.
abstract: The spatial distribution of the intracellular free Ca2+ (Ca2+i) rise elicited by different stimuli in bovine adrenal chromaffin cells was examined in single fura-2-loaded cells. In response to the potent secretagogues nicotine and high K+, Ca2+i was initially localized exclusively to the entire subplasmalemmal area of the cell. In response to the ineffective secretagogues, methacholine and muscarine, the rise in Ca2+i originated only in one pole of the cell and even at the peak of the response Ca2+ was still generally restricted to this same area of the cell. These results suggest that the triggering of exocytosis from these cells requires a specific spatial distribution of Ca2+i.
authors.affiliation: AFRC Unit of Insect Neurophysiology and Pharmacology, Department of Zoology, Cambridge, England.
authors.forename: T R
authors.initials: TR
authors.lastname: Cheek
authors.forename: A J
authors.initials: AJ
authors.lastname: O'Sullivan
authors.forename: R B
authors.initials: RB
authors.lastname: Moreton
authors.forename: M J
authors.initials: MJ
authors.lastname: Berridge
authors.forename: R D
authors.initials: RD
authors.lastname: Burgoyne
mesh_terms: D000313:Adrenal Medulla / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001572:Benzofurans; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D002838:Chromaffin System / Q000187:drug effects / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D005456:Fluorescent Dyes; D016257:Fura-2; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D016210:Methacholine Chloride; D008688:Methacholine Compounds / Q000494:pharmacology; D009116:Muscarine / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000502:physiology*; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000502:physiology*; D013873:Thionucleotides / Q000494:pharmacology
chemical_list: D001572:Benzofurans; D005456:Fluorescent Dyes; D008688:Methacholine Compounds; D011976:Receptors, Muscarinic; D011978:Receptors, Nicotinic; D013873:Thionucleotides; D016210:Methacholine Chloride; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D009538:Nicotine; D009116:Muscarine; D006160:Guanosine Triphosphate; D011188:Potassium; D002118:Calcium; D016257:Fura-2