AI Article Synopsis

  • The study investigated how delta-9-THC affects responses in hippocampal CA1 pyramidal cells in rats at various doses and time intervals.
  • The results showed that THC increased paired pulse inhibition in a dose-dependent way, with some doses exciting cell responses and higher doses causing depression of those responses.
  • The findings suggest that THC's effects on the hippocampus may involve interactions with GABA-mediated activity.

Article Abstract

The effects of delta-9-tetrahydrocannabinol (delta-9-THC) on monosynaptic population responses in hippocampal CA1 pyramidal cells were examined in acute rats for several doses and at several post injection time periods. Delta-9-THC enhanced paired pulse inhibition in a dose-dependent manner; however biphasic dose effects were observed on cell responses during low frequency potentiation and on population spikes elicited by a conditioning stimulus. The biphasic responses were such that 2--4 mg/kg THC (IP) excited while 16 mg/kg depressed the stimulus elicited CA1 response. For low doses of THC slight biphasic time effects were observed. Evidence presented suggests that some of THC's actions on hippocampus may be due to direct or indirect actions on GABA-mediated activity.

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http://dx.doi.org/10.1016/0361-9230(82)90042-9DOI Listing

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