Year: 2016
Type: dissertation
Abstract: With oxygen deprivation the mammalian brain undergoes excito-toxic cell death but this does not occur in the anoxia tolerant goldfish. Since GABA is the major inhibitory neurotransmitter in the brain, I investigated its potential role in preventing hyper-excitability in goldfish telencephalon neurons. Utilizing patch-clamp technique, the electrical activities of both excitatory (pyramidal) and inhibitory (stellate) neurons were recorded. With anoxia, membrane potential depolarized in both cell types. While pyramidal cells remained mostly quiescent, action-potential frequency of the stellate neurons increased. Further, the GABAA receptor reversal potential (EÂŹGABA) was depolarizing in both cell types. Inhibition of GABAA receptors reversed the anoxic response, while GABAB receptor inhibition did not induce a response. Co-antagonism of both GABAA/B receptors generated seizure-like neuronal activity. I conclude that GABA is vital for the anoxic survival of the goldfish and that the increased stellate neuron activity likely results in inhibition of pyramidal neuron activity with anoxia.
Source: TSpace (University of Toronto)
Author: Nariman Hossein‐Javaheri
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2586364216