» Articles » PMID: 15695331

Abnormal GABAA Receptors from the Human Epileptic Hippocampal Subiculum Microtransplanted to Xenopus Oocytes

Overview
Specialty Science
Date 2005 Feb 8
PMID 15695331
Citations 21
Authors
Affiliations
Soon will be listed here.
Abstract

We studied the properties of GABAA receptors microtransplanted from the human temporal lobe epilepsy (TLE)-associated brain regions to Xenopus oocytes. Cell membranes, isolated from surgically resected brain specimens of drug-resistant TLE patients, were injected into frog oocytes, which rapidly incorporated human GABAA receptors, and any associated proteins, into their surface membrane. The receptors originating from different epileptic brain regions had a similar run-down but an affinity for GABA that was approximately 60% lower for the subiculum receptors than for receptors issuing from the hippocampus proper or the temporal lobe neocortex. Moreover, GABA currents recorded in oocytes injected with membranes from the subiculum had a more depolarized reversal potential compared with the hippocampus proper or neocortex of the same patients. Quantitative RT-PCR analysis was performed of the GABAA receptor alpha1- to alpha5-, beta1- to beta3-, gamma2- to gamma3-, and delta-subunit mRNAs. The levels of expression of the alpha3-, alpha5-, and beta1- to beta3- subunit mRNAs are significantly higher, with the exception of gamma2-subunit whose expression is lower, in subiculum compared with neocortex specimens. Our results suggest that an abnormal GABA-receptor subunit transcription in the TLE subiculum leads to the expression of GABAA receptors with a relatively low affinity. This abnormal behavior of the subiculum GABAA receptors may contribute to epileptogenesis.

Citing Articles

Oocytes as a Powerful Cellular Model to Study Foreign Fully-Processed Membrane Proteins.

Ivorra I, Alberola-Die A, Cobo R, Gonzalez-Ros J, Morales A Membranes (Basel). 2022; 12(10).

PMID: 36295745 PMC: 9610954. DOI: 10.3390/membranes12100986.


Molecular Mechanisms of Epilepsy: The Role of the Chloride Transporter KCC2.

Belperio G, Corso C, Duarte C, Mele M J Mol Neurosci. 2022; 72(7):1500-1515.

PMID: 35819636 DOI: 10.1007/s12031-022-02041-7.


Mammalian Brain Ca Channel Activity Transplanted into Oocytes.

Rousset M, Humez S, Laurent C, Buee L, Blum D, Cens T Membranes (Basel). 2022; 12(5).

PMID: 35629822 PMC: 9146698. DOI: 10.3390/membranes12050496.


GABA Receptor Subunit Composition Drives Its Sensitivity to the Insecticide Fipronil.

Soualah Z, Taly A, Crespin L, Saulais O, Henrion D, Legendre C Front Neurosci. 2021; 15:768466.

PMID: 34912189 PMC: 8668240. DOI: 10.3389/fnins.2021.768466.


Synaptic Reshaping and Neuronal Outcomes in the Temporal Lobe Epilepsy.

Ren E, Curia G Int J Mol Sci. 2021; 22(8).

PMID: 33917911 PMC: 8068229. DOI: 10.3390/ijms22083860.


References
1.
Gibbs 3rd J, Shumate M, Coulter D . Differential epilepsy-associated alterations in postsynaptic GABA(A) receptor function in dentate granule and CA1 neurons. J Neurophysiol. 1997; 77(4):1924-38. DOI: 10.1152/jn.1997.77.4.1924. View

2.
Ben-Ari Y, Cossart R . Kainate, a double agent that generates seizures: two decades of progress. Trends Neurosci. 2000; 23(11):580-7. DOI: 10.1016/s0166-2236(00)01659-3. View

3.
Miledi R, Parker I . Chloride current induced by injection of calcium into Xenopus oocytes. J Physiol. 1984; 357:173-83. PMC: 1193253. DOI: 10.1113/jphysiol.1984.sp015495. View

4.
Wozny C, Kivi A, Lehmann T, Dehnicke C, Heinemann U, Behr J . Comment on "On the origin of interictal activity in human temporal lobe epilepsy in vitro". Science. 2003; 301(5632):463; author reply 463. DOI: 10.1126/science.1084237. View

5.
Assaf S, Chung S . Release of endogenous Zn2+ from brain tissue during activity. Nature. 1984; 308(5961):734-6. DOI: 10.1038/308734a0. View