title: Activity of lactate dehydrogenase in serum and cerebral cortex of immature and mature rats after hypobaric hypoxia.
abstract: In our previous studies we have found both an increase of lipid peroxidation damage (expressed as levels of thiobarbituric acid-reactive substances) in brain and plasma lactate concentration in 21-day-old rats after a 30-min exposure to hypobaric hypoxia. Pretreatment of rats with L-carnitine decreased both parameters. The aim of our present study was to determine if the L-carnitine-dependent decrease of plasma lactate could be due to a modification of lactate dehydrogenase (LDH) activity. We followed brain and blood serum LDH activity of 14-, 21- and 90-day-old Wistar rats. We found an increase of brain LDH activity with age. However, we did not observe any significant differences in LDH activity after exposure to hypobaric hypoxia or L-carnitine pretreatment. In contrast to brain, serum LDH activity did not show any clear age-dependence. The hypoxia exposure increased LDH activity of 21-day-old rats only. Pretreatment of rats with L-carnitine decreased serum LDH activity of 21- and 90-day-old rats probably due to membrane stabilizing role of L-carnitine. In conclusions, acute hypobaric hypoxia and/or L-carnitine pretreatment modified serum but not brain LDH activity.
authors.affiliation: First Faculty of Medicine, Institute of Physiology, Charles University, 128 00 Prague 2, Czech Republic.
authors.forename: Jitka
authors.initials: J
authors.lastname: Koudelová
authors.forename: Hana
authors.initials: H
authors.lastname: Rauchová
authors.forename: Martina
authors.initials: M
authors.lastname: Vokurková
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000201:enzymology*; D005260:Female; D000860:Hypoxia / Q000201:enzymology*; D007770:L-Lactate Dehydrogenase / Q000097:blood / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D007770:L-Lactate Dehydrogenase