title: Local regulation of L-type Ca²⁺ channel sparklets in arterial smooth muscle.
abstract: This review addresses the latest advances in our understanding of the regulation of a novel Ca²⁺ signal called L-type Ca²⁺ channel sparklets in arterial smooth muscle. L-type Ca²⁺ channel sparklets are elementary Ca²⁺ influx events produced by the opening of a single or a small cluster of L-type Ca²⁺ channels. These Ca²⁺ signals were first visualized in the vasculature in arterial smooth muscle cells. In these cells, L-type Ca²⁺ channel sparklets display two functionally distinct gating modalities that regulate local and global [Ca²⁺](i). The activity of L-type Ca²⁺ channel sparklets varies regionally within a cell depending on the dynamic activity of a cohort of protein kinases and phosphatases recruited to L-type Ca²⁺ channels in the arterial smooth muscle sarcolemma in a complex coordinated by the scaffolding molecule AKAP150. We also described a mechanism whereby clusters of L-type Ca²⁺ channels gate cooperatively to amplify intracellular Ca²⁺ signals with likely pathological consequences.
authors.affiliation: Department of Pharmacology, University of California, Davis, California, USA. mfnavedo@ucdavis.edu
authors.forename: Manuel F
authors.initials: MF
authors.lastname: Navedo
authors.forename: Gregory C
authors.initials: GC
authors.lastname: Amberg
mesh_terms: D054758:A Kinase Anchor Proteins / Q000378:metabolism; D000818:Animals; D001158:Arteries / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D006801:Humans; D015640:Ion Channel Gating / Q000502:physiology*; D009124:Muscle Proteins / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D012508:Sarcolemma / Q000378:metabolism*
chemical_list: D054758:A Kinase Anchor Proteins; C487775:AKAP5 protein, human; D020746:Calcium Channels, L-Type; D009124:Muscle Proteins; D002118:Calcium