{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T10:56:40Z","timestamp":1785322600072,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,17]],"date-time":"2021-12-17T00:00:00Z","timestamp":1639699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["RGPIN-2018-04401"],"award-info":[{"award-number":["RGPIN-2018-04401"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Institute of Health","award":["R01 AG055357"],"award-info":[{"award-number":["R01 AG055357"]}]},{"name":"Aging Research Center \u2013 Newfoundland and Labrador","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>In the hippocampus, the contributions of N-methyl-D-aspartate receptors (NMDARs) and L-type calcium channels (LTCCs) to neuronal transmission and synaptic plasticity change with aging, underlying calcium dysregulation and cognitive dysfunction. However, the relative contributions of NMDARs and LTCCs in other learning encoding structures during aging are not known. The piriform cortex (PC) plays a significant role in odor associative memories, and like the hippocampus, exhibits forms of long-term synaptic plasticity. Here, we investigated the expression and contribution of NMDARs and LTCCs in long-term depression (LTD) of the PC associational fiber pathway in three cohorts of Sprague Dawley rats: neonatal (1\u20132 weeks), young adult (2\u20133 months) and aged (20\u201325 months). Using a combination of slice electrophysiology, Western blotting, fluorescent immunohistochemistry and confocal imaging, we observed a shift from an NMDAR to LTCC mediation of LTD in aged rats, despite no difference in the amount of LTD expression. These changes in plasticity are related to age-dependent differential receptor expression in the PC. LTCC Cav1.2 expression relative to postsynaptic density protein 95 is increased in the associational pathway of the aged PC layer Ib. Enhanced LTCC contribution in synaptic depression in the PC may contribute to altered olfactory function and learning with aging.<\/jats:p>","DOI":"10.3390\/ijms222413551","type":"journal-article","created":{"date-parts":[[2021,12,19]],"date-time":"2021-12-19T20:37:27Z","timestamp":1639946247000},"page":"13551","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Age-Dependent Contributions of NMDA Receptors and L-Type Calcium Channels to Long-Term Depression in the Piriform Cortex"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3682-7208","authenticated-orcid":false,"given":"Vishaal","family":"Rajani","sequence":"first","affiliation":[{"name":"Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John\u2019s, NL A1B 3V6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aida","family":"Maziar","sequence":"additional","affiliation":[{"name":"Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John\u2019s, NL A1B 3V6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kwun Nok Mimi","family":"Man","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, School of Medicine, University of California at Davis, Davis, CA 95616-5270, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johannes W.","family":"Hell","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, School of Medicine, University of California at Davis, Davis, CA 95616-5270, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9837-8495","authenticated-orcid":false,"given":"Qi","family":"Yuan","sequence":"additional","affiliation":[{"name":"Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John\u2019s, NL A1B 3V6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.conb.2020.03.001","article-title":"Odor coding in piriform cortex: Mechanistic insights into distributed coding","volume":"64","author":"Blazing","year":"2020","journal-title":"Curr. 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