title: Activation of NMDA receptors prevents excessive metabolic decrease in hypoxic rat pups.
abstract: We tested the hypothesis that glutamate NMDA receptors may help maintain metabolic rate and body temperature during acute or chronic hypoxic exposure in newborn rats. We recorded ventilation, metabolism ((.)V(O(2)) -- ((.)V(CO(2)) and rectal temperature, under normoxia, acute hypoxia (30 min -- 12% O(2)), or following 10 days of chronic hypoxia, in 10 days old male and female rats, receiving saline i.p. injection or the NMDA receptor antagonist MK-801. Acute hypoxia decreased rectal temperature and metabolism, and increased ventilation, and (.)V(E)/((.)V(O(2) and (.)V(E)/((.)V(CO(2) to the same extent in males and females. MK-801 injection amplified the metabolic decrease under acute (in males and females) and chronic (in males) hypoxia, prevented the increase of minute ventilation, while (.)V(E)/((.)V(O(2) or (.)V(E)/((.)V(CO(2)remained constant. Hence, NMDA glutamate receptors help to maintain metabolic rate, minute ventilation and body temperature at a determined level in acute (males and females) and chronic hypoxia (males only).
authors.affiliation: Department of Pediatrics, Laval University, Centre de Recherche (D0-711), Hôpital St-François d'Assise, 10 rue de l'Espinay, Que. (QC), Canada G1L 3L5.
authors.forename: Mirza Shafiulla
authors.initials: MS
authors.lastname: Baig
authors.forename: Vincent
authors.initials: V
authors.lastname: Joseph
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D000860:Hypoxia / Q000188:drug therapy / Q000378:metabolism*; D008297:Male; D008660:Metabolism / Q000187:drug effects / Q000502:physiology*; D011247:Pregnancy; D011659:Pulmonary Gas Exchange / Q000187:drug effects / Q000502:physiology; D012123:Pulmonary Ventilation / Q000187:drug effects / Q000502:physiology; D011897:Random Allocation; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology*; D012737:Sex Factors; D013997:Time Factors
chemical_list: D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate