title: Flicker-assisted localization microscopy reveals altered mitochondrial architecture in hypertension.
abstract: Mitochondrial morphology is central to normal physiology and disease development. However, in many live cells and tissues, complex mitochondrial structures exist and morphology has been difficult to quantify. We have measured the shape of electrically-discrete mitochondria, imaging them individually to restore detail hidden in clusters and demarcate functional boundaries. Stochastic "flickers" of mitochondrial membrane potential were visualized with a rapidly-partitioning fluorophore and the pixel-by-pixel covariance of spatio-temporal fluorescence changes analyzed. This Flicker-assisted Localization Microscopy (FaLM) requires only an epifluorescence microscope and sensitive camera. In vascular myocytes, the apparent variation in mitochondrial size was partly explained by densely-packed small mitochondria. In normotensive animals, mitochondria were small spheres or rods. In hypertension, mitochondria were larger, occupied more of the cell volume and were more densely clustered. FaLM provides a convenient tool for increased discrimination of mitochondrial architecture and has revealed mitochondrial alterations that may contribute to hypertension.
authors.affiliation: Strathclyde Institute of Pharmacy &Biomedical Sciences, 161 Cathedral Street, University of Strathclyde, Glasgow G4 0RE, UK.
authors.forename: Susan
authors.initials: S
authors.lastname: Chalmers
authors.affiliation: Department of Physics, Durham University, South Road, Durham DH1 3LE, UK.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Saunter
authors.affiliation: Department of Physics, Durham University, South Road, Durham DH1 3LE, UK.
authors.forename: John M
authors.initials: JM
authors.lastname: Girkin
authors.affiliation: Strathclyde Institute of Pharmacy &Biomedical Sciences, 161 Cathedral Street, University of Strathclyde, Glasgow G4 0RE, UK.
authors.forename: John G
authors.initials: JG
authors.lastname: McCarron
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000473:pathology / Q000503:physiopathology; D006973:Hypertension / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D053078:Membrane Potential, Mitochondrial; D008856:Microscopy, Fluorescence / Q000379:methods; D008928:Mitochondria / Q000473:pathology / Q000648:ultrastructure*; D051336:Mitochondrial Membranes / Q000648:ultrastructure; D009131:Muscle, Smooth, Vascular / Q000473:pathology / Q000648:ultrastructure*; D032389:Myocytes, Smooth Muscle / Q000473:pathology / Q000648:ultrastructure*; D053141:Organelle Size; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY