caa a22 4500 445852879 CHVBK 20180317145418.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s00204-010-0637-2 doi (NATIONALLICENCE)springer-10.1007/s00204-010-0637-2 Existence of a threshold for hydroxyl radical generation independent of hypoxia in rat striatum during carbon monoxide poisoning [Elektronische Daten] [Shuichi Hara, Hajime Mizukami, Kunihiko Kurosaki, Fumi Kuriiwa, Toshiji Mukai] We examined the role of hypoxia in the carbon monoxide (CO)-induced generation of the hydroxyl radical (•OH) in the striatum, which could contribute to brain damage due to CO poisoning. Exposure of free-moving rats to 1,000 and 3,000ppm CO or 8 and 5% O2 for 40min caused concentration-dependent hypoxic conditions in terms of carboxyhemoglobin (COHb), deoxyhemoglobin, oxyhemoglobin, and O2 contents in arterial blood. The hypoxic conditions seemed comparable between 3,000ppm CO and 5% O2, although alterations of pH and partial O2 pressure (PO2) were complex and concentration independent. In the striatum, CO and low O2 decreased tissue PO2 levels in a concentration-dependent and concentration-independent manner, respectively, but levels at the end of exposure were comparable among all groups. This was also the case for the increase in striatal blood flow. Although the increases in extracellular glutamate (excitatory), taurine (inhibitory), and alanine (non-neurotransmitter), in the striatum in response to CO and low O2 were complex, 3,000ppm CO and 5% O2 had comparable effects. Thus, 3,000ppm CO and 5% O2 seemed to induce comparable hypoxic conditions. Nevertheless, the former more strongly stimulated •OH generation in the striatum than the latter. In addition, in contrast to low O2 which caused a concentration-dependent increase in •OH, 1,000ppm CO had no effect. The findings suggest that striatal •OH generation due to CO poisoning may be independent of hypoxia per se and that a threshold might exist. Springer-Verlag, 2011 Carbon monoxide nationallicence Brain hypoxia nationallicence Rat striatum nationallicence Hydroxyl radical nationallicence Hara Shuichi Department of Forensic Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, 160-8402, Tokyo, Japan aut Mizukami Hajime Department of Forensic Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, 160-8402, Tokyo, Japan aut Kurosaki Kunihiko Department of Legal Medicine, Toho University School of Medicine, 5-21-16 Omorinishi, Ota-ku, 143-8540, Tokyo, Japan aut Kuriiwa Fumi Department of Forensic Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, 160-8402, Tokyo, Japan aut Mukai Toshiji Department of Legal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, 216-8511, Kanagawa, Japan aut Archives of Toxicology Springer-Verlag 85/9(2011-09-01), 1091-1099 0340-5761 85:9<1091 2011 85 204 https://doi.org/10.1007/s00204-010-0637-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00204-010-0637-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hara Shuichi Department of Forensic Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, 160-8402, Tokyo, Japan aut NATIONALLICENCE 700 1- Mizukami Hajime Department of Forensic Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, 160-8402, Tokyo, Japan aut NATIONALLICENCE 700 1- Kurosaki Kunihiko Department of Legal Medicine, Toho University School of Medicine, 5-21-16 Omorinishi, Ota-ku, 143-8540, Tokyo, Japan aut NATIONALLICENCE 700 1- Kuriiwa Fumi Department of Forensic Medicine, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, 160-8402, Tokyo, Japan aut NATIONALLICENCE 700 1- Mukai Toshiji Department of Legal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, 216-8511, Kanagawa, Japan aut NATIONALLICENCE 773 0- Archives of Toxicology Springer-Verlag 85/9(2011-09-01), 1091-1099 0340-5761 85:9<1091 2011 85 204 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer