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The Minho Objective Rodent Phenotypical Anesthesia (MORPhA) scale was tested in mice and rats anaesthetized with a mixture of ketamine\/dexmedetomidine (ket\/dex - 3 doses). The scale comprises 12 behavioral readouts organized in 5 stages \u2013 (i) normal\/(ii) hindered voluntary movement, elicited response to (iii) non-noxious\/(iv) noxious stimuli and (v) absence of response \u2013 evaluated at regular time points. Progression across stages was monitored by electroencephalography (EEG) in rats during anesthesia induction and reversal (atipamezole) and during induction with a second anesthetic drug (pentobarbital). Higher anesthetic doses decreased the time to reach higher levels of anesthesia during progression, while increasing the time to regain waking behavior during reversal, in mice and in rats. A regular decrease in high frequencies (low and high gamma) power was observed as the MORPhA score increased during anesthesia induction, while the opposite pattern was observed during emergence from anesthesia through reversion of dex effect. The devised anesthetic scale is of simple application and provides a semi-quantifiable readout of anesthesia induction\/reversal.<\/jats:p>","DOI":"10.1101\/475921","type":"posted-content","created":{"date-parts":[[2018,11,26]],"date-time":"2018-11-26T04:34:01Z","timestamp":1543206841000},"source":"Crossref","is-referenced-by-count":0,"title":["MORPhA Scale: behavioral and electroencephalographic validation of a rodent anesthesia scale"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6674-1256","authenticated-orcid":false,"given":"Madalena","family":"Esteves","sequence":"first","affiliation":[]},{"given":"Ant\u00f3nio M","family":"Almeida","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8257-3413","authenticated-orcid":false,"given":"Joana","family":"Silva","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2800-3903","authenticated-orcid":false,"given":"Pedro Silva","family":"Moreira","sequence":"additional","affiliation":[]},{"given":"Emanuel","family":"Carvalho","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9497-6543","authenticated-orcid":false,"given":"Jos\u00e9 Miguel","family":"P\u00eago","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6233-4693","authenticated-orcid":false,"given":"Armando","family":"Almeida","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0115-0038","authenticated-orcid":false,"given":"Ioannis","family":"Sotiropoulos","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8755-5126","authenticated-orcid":false,"given":"Nuno","family":"Sousa","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5566-0386","authenticated-orcid":false,"given":"Hugo","family":"Leite-Almeida","sequence":"additional","affiliation":[]}],"member":"54368","reference":[{"key":"2019072212251456000_475921v1.1","doi-asserted-by":"crossref","first-page":"R396","DOI":"10.1152\/ajpregu.00776.2005","article-title":"Urethane inhibits the GABAergic neurotransmission in the nucleus of the solitary tract of rat brain stem slices","volume":"292","year":"2007","journal-title":"Am J Physiol Regul Integr Comp Physiol"},{"key":"2019072212251456000_475921v1.2","doi-asserted-by":"publisher","DOI":"10.1016\/S0889-1591(02)00021-1"},{"key":"2019072212251456000_475921v1.3","doi-asserted-by":"crossref","first-page":"1051","DOI":"10.1016\/S0022-3565(24)37128-9","article-title":"Pharmacokinetic-pharmacodynamic characterization of the cardiovascular, hypnotic, EEG and ventilatory responses to dexmedetomidine in the rat","volume":"283","year":"1997","journal-title":"J Pharmacol Exp Ther"},{"key":"2019072212251456000_475921v1.4","doi-asserted-by":"publisher","DOI":"10.1016\/S0304-3959(01)00345-1"},{"key":"2019072212251456000_475921v1.5","doi-asserted-by":"publisher","DOI":"10.1007\/BF01852390"},{"key":"2019072212251456000_475921v1.6","doi-asserted-by":"publisher","DOI":"10.1258\/002367788780746331"},{"key":"2019072212251456000_475921v1.7","doi-asserted-by":"publisher","DOI":"10.1258\/002367793780745471"},{"key":"2019072212251456000_475921v1.8","doi-asserted-by":"crossref","first-page":"056006","DOI":"10.1088\/1741-2560\/12\/5\/056006","article-title":"A PK-PD model of ketamine-induced high-frequency oscillations","volume":"12","year":"2015","journal-title":"J Neural Eng"},{"key":"2019072212251456000_475921v1.9","first-page":"605","article-title":"Circulatory, respiratory and acid-base balance changes produced by anesthetics in the rat","volume":"35","year":"1976","journal-title":"Acta Biol Med Ger"},{"key":"2019072212251456000_475921v1.10","unstructured":"Gaertner, D.J. , Hallman, T.M. , Hankenson, F.C. , and Batchelder, M.A. (2008). \u201cAnesthesia and Analgesia for Laboratory Rodents,\u201d in Anesthesia and Analgesia in Laboratory Animals, 2nd Edition. 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