Intracellular calcium signals in the surround of rat visual cortex lesions.
Focal lesions of the visual cortex induce deafferentiation, excitotoxic cell death as well as functional reorganization in the surrounding tissue. The intracellular second messenger calcium is involved in a wide range of cellular responses including excitotoxicity and functional reorganization following cortical injuries. We investigated the intracellular calcium concentration [Ca2+]i in neurons of the visual cortex using fluorescence imaging of fura-2 signals in a slice preparation obtained from lesioned and sham-operated cortices. We observed an increase in resting and stimulus evoked [Ca2+]i in the surround of the lesion, which were mediated by NMDA and non-NMDA ionotropic glutamate receptors. This increase in [Ca2+]i might be an important factor for lesion-induced functional reorganization in the rat visual cortex.
Barmashenko
G
G
Department of Neurophysiology MA 4/149, Ruhr-University Bochum, D-44780 Bochum, Germany.
Eysel
U T
UT
Mittmann
T
T
D000818:Animals; D001930:Brain Injuries / Q000378:metabolism* / Q000503:physiopathology; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D004558:Electric Stimulation; D016257:Fura-2 / Q000493:pharmacokinetics; D007424:Intracellular Fluid / Q000378:metabolism*; D017774:Long-Term Potentiation / Q000502:physiology; D009410:Nerve Degeneration / Q000378:metabolism* / Q000503:physiopathology; D009416:Nerve Regeneration / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D017470:Receptors, Glutamate / Q000187:drug effects / Q000378:metabolism; D020127:Recovery of Function / Q000502:physiology; D014793:Visual Cortex / Q000378:metabolism* / Q000503:physiopathology
D017470:Receptors, Glutamate; D002118:Calcium; D016257:Fura-2