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PubMed · 16040283

Activation of NMDA receptors prevents excessive metabolic decrease in hypoxic rat pups.

Mirza Shafiulla Baig·Vincent Joseph
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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).

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Analysis of VarianceAnimalsAnimals, NewbornBody TemperatureDizocilpine MaleateExcitatory Amino Acid AntagonistsFemaleHypoxiaMaleMetabolismPregnancyPulmonary Gas ExchangePulmonary VentilationRandom AllocationRatsReceptors, N-Methyl-D-AspartateSex FactorsTime FactorsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

Mirza Shafiulla Baig, Vincent Joseph. 2005-07-22. Activation of NMDA receptors prevents excessive metabolic decrease in hypoxic rat pups.. https://doi.org/10.1016/j.resp.2005.06.008

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