Age-related alterations in the properties of hippocampal pyramidal neurons among rat strains.
We compared age-related alterations in the electrophysiological and pharmacological properties of CA1 hippocampal pyramidal neurons in three strains of rats (Sprague-Dawley, Fisher 344, and Wistar) at 3-4 and 25-32 months of age, using the in vitro slice preparation. The most consistent age-related alterations in the properties of rat hippocampal neurons were: a decrease in membrane excitability, a decrease in the amplitude and duration of inhibitory postsynaptic potentials and a decreased sensitivity to the effect of the cholinergic agonist carbachol. In contrast, no consistent alterations in calcium-dependent events were observed in these strains of rats. The age-related changes in the duration of the afterhyperpolarizations (AHPs) were different (and even opposite) depending on the strain studied. Our results show that age-related changes observed in a given strain are not necessarily present in all strains of the same species.
Potier
B
B
Laboratoire de Physiopharmacologie du Système Nerveux, INSERM U 161, Paris, France.
Lamour
Y
Y
Dutar
P
P
D000375:Aging / Q000502:physiology*; D000818:Animals; D001418:Baclofen / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism / Q000502:physiology; D002217:Carbachol / Q000494:pharmacology; D004594:Electrophysiology; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011712:Pyramidal Tracts / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011916:Rats, Inbred F344; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013045:Species Specificity; D013569:Synapses / Q000502:physiology
D002217:Carbachol; D001418:Baclofen; D002118:Calcium