These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: In vitro electrophysiology of rat subicular bursting neurons.
    Author: Mattia D, Kawasaki H, Avoli M.
    Journal: Hippocampus; 1997; 7(1):48-57. PubMed ID: 9138668.
    Abstract:
    Intracellular recordings were used to study the electrophysiological properties of rat subicular neurons in a brain slice preparation in vitro. Cells were classified as bursting neurons (n = 102) based on the firing pattern induced by depolarizing current pulses. The bursting response recorded at resting membrane potential (-66.1 +/- 6.2 mV, mean +/- SD n = 94) was made up of a cluster of fast action potentials riding on a slow depolarization and was followed by an afterhyperpolarization. Tonic firing occurred at a membrane potential of approximately -55 mV. A burst also occurred upon termination of a hyperpolarizing current pulse. Tetrodotoxin (TTX, 1 microM) blocked the burst and decreased or abolished the underlying slow depolarization. These effects were not induced by the concomitant application of the Ca2+ channel blockers Co2+ (2 mM) and Cd2+ (1 mM). Subicular bursting neurons displayed voltage- and time-dependent inward rectifications of the membrane during depolarizing and hyperpolarizing current pulses. The inward rectification in the depolarizing direction was abolished by TTX, while that in the hyperpolarizing direction was blocked by extracellular Cs+ (3 mM), but not modified by Ba2+ (0.5-1 mM), TTX, or Co2+ and Cd2+. Tetraethylammonium (10 mM)-sensitive, outward rectification became apparent in the presence of TTX. These results suggest that neurons in the rat subiculum can display voltage-dependent bursts of action potentials as well as membrane rectification in the depolarizing and hyperpolarizing directions. These results also indicate that activation of a voltage-gated Na+ conductance may be instrumental in the initiation of bursting activity.
    [Abstract] [Full Text] [Related] [New Search]