{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T22:19:56Z","timestamp":1771625996683,"version":"3.50.1"},"reference-count":0,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[1980,10,1]],"date-time":"1980-10-01T00:00:00Z","timestamp":339206400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["The Journal of Physiology"],"published-print":{"date-parts":[[1980,10]]},"abstract":"<jats:p>1. The depressant actions of Mg2+ and a range of other divalent ions on synaptic excitation and on responses produced by excitatory amino acids and other putative transmitters have been investigated in hemisected isolated spinal cords of frogs and neonatal rats. Some comparative studies were also made using the rat isolated superior cervical ganglion. 2. At concentrations above 10 microM, Mg2+ selectively antagonized N\u2010methyl\u2010D\u2010aspartate (NMDA)\u2010induced motoneurone depolarization as recorded from ventral roots of tetrodotoxin\u2010blocked spinal cords. Depolarization evoked by quisqualate (unaffected by 20 mM\u2010Mg2+) was resistant to the depressant action of these ions, while depolarizations evoked by other excitant amino acids were depressed to intermediate degrees. 3. Mn2+, Co2+ and Ni2+ had qualitatively similar actions to Mg2+; Mn2+ was somewhat less potent and Co2+ and Ni2+ more potent than Mg2+. The alkaline earth metal ions, Ca2+, Sr2+ and Ba2+, had very weak Mg2+\u2010like actions. Ca2+ and Mg2+ acted additively in depressing amino acid\u2010induced responses. 4. Mg2+ also depressed motoneurone responses evoked by noradrenaline, substance P and carbachol in the neonatal rat isolated spinal cord. However, none of these effects were as marked as the depression of NMDA\u2010induced responses by Mg2+ in this preparation. Mg2+ did not depress motoneurone depolarization produced by 5\u2010HT in the rat spinal cord or the depolarizing action of GABA on primary afferent terminals of the isolated frog spinal cord. 5. At concentrations producing marked depression of NMDA\u2010induced responses, Mg2+ also depressed synaptic transmission in spinal cords in the absence of an effect on ganglionic transmission. At the same concentrations, Mn2+, Co2+ and Ni2+ depressed synaptic transmission in both preparations. 6. From the similarity in action between Mg2+ and the D\u2010alpha\u2010aminoadipate group of NMDA antagonists, it is suggested that the central depressant action of low concentrations of Mg2+ involves predominantly a postsynaptically mediated interference with the action of an excitatory amino acid transmitter.<\/jats:p>","DOI":"10.1113\/jphysiol.1980.sp013443","type":"journal-article","created":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T07:20:47Z","timestamp":1418973647000},"page":"413-428","source":"Crossref","is-referenced-by-count":319,"title":["Selective depression of excitatory amino acid induced depolarizations by magnesium ions in isolated spinal cord preparations."],"prefix":"10.1113","volume":"307","author":[{"given":"B","family":"Ault","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"R H","family":"Evans","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A A","family":"Francis","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"D J","family":"Oakes","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J C","family":"Watkins","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[1980,10]]},"container-title":["The Journal of Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1113%2Fjphysiol.1980.sp013443","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/pdf\/10.1113\/jphysiol.1980.sp013443","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,11,5]],"date-time":"2023-11-05T23:35:27Z","timestamp":1699227327000},"score":1,"resource":{"primary":{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/10.1113\/jphysiol.1980.sp013443"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1980,10]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1980,10]]}},"alternative-id":["10.1113\/jphysiol.1980.sp013443"],"URL":"https:\/\/doi.org\/10.1113\/jphysiol.1980.sp013443","archive":["Portico"],"relation":{},"ISSN":["0022-3751","1469-7793"],"issn-type":[{"value":"0022-3751","type":"print"},{"value":"1469-7793","type":"electronic"}],"subject":[],"published":{"date-parts":[[1980,10]]}}}