Intracellular calcium stores contribute to increased susceptibility to LTD induction during aging.
Release of Ca(2+) from intracellular Ca(2+) stores (ICS) is involved in age-related changes in the induction of long-term potentiation. However, the role of this Ca(2+) source for the increased susceptibility to long-term depression (LTD) with advanced age is unknown. Extracellular excitatory postsynaptic field potentials were recorded from CA3-CA1 synaptic contacts from hippocampal slices obtained from young (5-8 months) and aged (22-24 months) male Fischer 344 rats. Blockade of Ca(2+)-release from ICS by cyclopiazonic acid, thapsigargin, or ryanodine blocked LTD induction in aged rats. Impaired LTD was not simply due to a loss of a Ca(2+) source. The idea that ICS may play prominent role in regulating synaptic modifiability through regulation of cell excitability and the timing of pre and postsynaptic activity is discussed.
Kumar
Ashok
A
Department of Neuroscience, McKnight Brain Institute, University of Florida, PO Box 100244, Gainesville, FL 32610-0244, USA.
Foster
Thomas C
TC
D000375:Aging / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D007211:Indoles / Q000494:pharmacology; D036881:Long-Term Synaptic Depression / Q000502:physiology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D012433:Ryanodine / Q000494:pharmacology; D019284:Thapsigargin / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007211:Indoles; D012433:Ryanodine; D019284:Thapsigargin; D002118:Calcium; C000543:cyclopiazonic acid