title: Alteration of blood glucose levels in the rat following exposure to hyperbaric oxygen.
abstract: Findings regarding blood glucose level (BGL) on exposure to hyperbaric oxygen (HBO) are contradictory. We investigated the influence of HBO on BGL, and of BGL on latency to central nervous system oxygen toxicity (CNS-OT). The study was conducted on five groups of rats: Group 1, exposure to oxygen at 2.5 atmospheres absolute (ATA), 90 min/day for 7 days; Group 2, exposure to oxygen once a week from 2 to 6 ATA in increments of 1 ATA/wk, for a period of time calculated as 60% of the latency to CNS-OT (no convulsions); Group 3, exposure to 6 ATA breathing a gas mixture with a pO2 of 0.21; Group 4, received 10 U/kg insulin to induce hypoglycemia before exposure to HBO; Group 5, received 33% glucose to induce hyperglycemia before exposure to HBO. Blood samples were drawn before and after exposures for measurement of BGL. No change was observed in BGL after exposure to oxygen at 2.5 ATA, 90 min/day for 7 days. BGL was significantly elevated after exposure to oxygen at 6 ATA until the appearance of convulsions, and following exposure to 4, 5, and 6 ATA without convulsions (P < 0.01). No change was observed in BGL after exposure to 6 ATA breathing a gas mixture with a pO2 of 0.21. Hypoglycemia shortened latency to CNS oxygen toxicity, whereas hyperglycemia had no effect. Our results demonstrate an influence of HBO exposure on elevation of BGL, starting at 4 ATA. This implies that BGL may serve as a marker for the generation of CNS-OT.
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel meri_mehkar@bezeqint.net emirit@netvision.net.il.
authors.forename: Mirit
authors.initials: M
authors.lastname: Eynan
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel.
authors.forename: Michael
authors.initials: M
authors.lastname: Mullokandov
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel.
authors.forename: Nitzan
authors.initials: N
authors.lastname: Krinsky
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Biram
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel.
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Arieli
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000187:drug effects*; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D006931:Hyperbaric Oxygenation / Q000009:adverse effects*; D018496:Hyperoxia / Q000139:chemically induced / Q000378:metabolism; D008297:Male; D010100:Oxygen / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration / Q000187:drug effects; D012640:Seizures / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D005947:Glucose; D010100:Oxygen
keywords: blood glucose level; central nervous system oxygen toxicity; hyperbaric oxygen; hypoglycemia