Age-related changes in potentiation of evoked responses in CA1 pyramidal cells from the hamster hippocampus.
Hippocampal responses were compared in 16 old (15-22 month) and 14 young (2-5 month) Syrian hamsters to determine if this species showed age-dependent changes in potentiation. Population spike amplitude increased following tetanus by 84.1+/-20.0% in slices from young animals and by 51.1+/-6.3% in slices from old animals (P<0.05). In addition, I-O curves (plots of population spike amplitude vs. intensity of Schaffer collateral excitation) were obtained before and after tetanus. While regions of I-O curves near threshold and saturation showed no significant change, the slope at the midpoint of the I-O curve increased by 152.3+/-68.4% in slices from young animals and by 13.7 +/-10.0% in slices from old animals (P<0.05). Thus, in old hamsters (as in rats) potentiation was impaired and slope changes of I/O curves clearly displayed this deficit.
Shahlaie
K
K
Section of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95616, USA.
Kargozaran
H
H
Horowitz
J M
JM
D000200:Action Potentials / Q000502:physiology; D000375:Aging / Q000502:physiology*; D000818:Animals; D006224:Cricetinae; D005071:Evoked Potentials / Q000502:physiology; D006624:Hippocampus / Q000166:cytology* / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D008647:Mesocricetus; D009473:Neuronal Plasticity / Q000502:physiology; D017966:Pyramidal Cells / Q000502:physiology*