{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T14:24:38Z","timestamp":1789050278818,"version":"build-2803163510"},"reference-count":26,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,10]],"date-time":"2022-11-10T00:00:00Z","timestamp":1668038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001407","name":"Department of Biotechnology, Ministry of Science and Technology, Govt. of India","doi-asserted-by":"publisher","award":["BT\/PR20392\/MED\/122\/26\/2016"],"award-info":[{"award-number":["BT\/PR20392\/MED\/122\/26\/2016"]}],"id":[{"id":"10.13039\/501100001407","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Glutamate-receptor-mediated hyperexcitability contributes to seizure generation in temporal lobe epilepsy (TLE). Tryptophan\u2013kynurenine pathway (TKP) metabolites regulate glutamate receptor activity under physiological conditions. This study was designed to investigate alterations in the levels of TKP metabolites and the differential regulation of glutamatergic activity by TKP metabolites in the hippocampus, anterior temporal lobe (ATL), and neocortex samples of a lithium\u2013pilocarpine rat model of TLE. We observed that levels of tryptophan were reduced in the hippocampus and ATL samples but unaltered in the neocortex samples. The levels of kynurenic acid were reduced in the hippocampus samples and unaltered in the ATL and neocortex samples of the TLE rats. The levels of kynurenine were unaltered in all three regions of the TLE rats. The magnitude of reduction in these metabolites in all regions was unaltered in the TLE rats. The frequency and amplitude of spontaneous excitatory postsynaptic currents were enhanced in hippocampus ATL samples but not in the neocortex samples of the TLE rats. The exogenous application of kynurenic acid inhibited glutamatergic activity in the slice preparations of all these regions in both the control and the TLE rats. However, the magnitude of reduction in the frequency of kynurenic acid was higher in the hippocampus (18.44 \u00b1 2.6% in control vs. 30.02 \u00b1 1.5 in TLE rats) and ATL (16.31 \u00b1 0.91% in control vs. 29.82 \u00b1 3.08% in TLE rats) samples of the TLE rats. These findings suggest the differential regulation of glutamatergic activity by TKP metabolites in the hippocampus, ATL, and neocortex of TLE rats.<\/jats:p>","DOI":"10.3390\/cells11223560","type":"journal-article","created":{"date-parts":[[2022,11,10]],"date-time":"2022-11-10T19:18:29Z","timestamp":1668107909000},"page":"3560","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Differential Levels of Tryptophan\u2013Kynurenine Pathway Metabolites in the Hippocampus, Anterior Temporal Lobe, and Neocortex in an Animal Model of Temporal Lobe Epilepsy"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9112-0723","authenticated-orcid":false,"given":"Soumil","family":"Dey","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi 110029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vivek","family":"Dubey","sequence":"additional","affiliation":[{"name":"Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3028-2259","authenticated-orcid":false,"given":"Aparna Banerjee","family":"Dixit","sequence":"additional","affiliation":[{"name":"Dr. B.R. Ambedkar Centre for Biomedical Research, University of Delhi, Delhi 110007, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manjari","family":"Tripathi","sequence":"additional","affiliation":[{"name":"Department of Neurology, All India Institute of Medical Sciences, New Delhi 110029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Poodipedi Sarat","family":"Chandra","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi 110029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5587-6067","authenticated-orcid":false,"given":"Jyotirmoy","family":"Banerjee","sequence":"additional","affiliation":[{"name":"Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1016\/0304-3940(84)90184-8","article-title":"Actions of excitatory amino acids and kynurenic acid in the primate hippocampus: A preliminary study","volume":"52","author":"Perkins","year":"1984","journal-title":"Neurosci. 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