title: Infrared inhibition of embryonic hearts.
abstract: Infrared control is a new technique that uses pulsed infrared lasers to thermally alter electrical activity. Originally developed for nerves, we have applied this technology to embryonic hearts using a quail model, previously demonstrating infrared stimulation and, here, infrared inhibition. Infrared inhibition enables repeatable and reversible block, stopping cardiac contractions for several seconds. Normal beating resumes after the laser is turned off. The block can be spatially specific, affecting propagation on the ventricle or initiation on the atrium. Optical mapping showed that the block affects action potentials and not just calcium or contraction. Increased resting intracellular calcium was observed after a 30-s exposure to the inhibition laser, which likely resulted in reduced mechanical function. Further optimization of the laser illumination should reduce potential damage. Stopping cardiac contractions by disrupting electrical activity with infrared inhibition has the potential to be a powerful tool for studying the developing heart.
authors.affiliation: Case Western Reserve University, Department of Pediatrics, 10900 Euclid Avenue, Cleveland, Ohio 44106, United StatesbCase Western Reserve University, Department of Biomedical Engineering, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States.
authors.forename: Yves T
authors.initials: YT
authors.lastname: Wang
authors.affiliation: Case Western Reserve University, Department of Biomedical Engineering, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Rollins
authors.affiliation: Case Western Reserve University, Department of Pediatrics, 10900 Euclid Avenue, Cleveland, Ohio 44106, United StatesbCase Western Reserve University, Department of Biomedical Engineering, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Jenkins
mesh_terms: D000200:Action Potentials / Q000528:radiation effects; D000818:Animals; D002118:Calcium / Q000032:analysis; D004625:Embryo, Nonmammalian; D006321:Heart / Q000000981:diagnostic imaging* / Q000196:embryology / Q000528:radiation effects; D007259:Infrared Rays; D007834:Lasers; D023421:Models, Animal; D009200:Myocardial Contraction / Q000528:radiation effects; D011784:Quail
chemical_list: D002118:Calcium