The effects of cold acclimation and nitric oxide on antioxidative enzymes in rat pancreas.
Alterations of pancreatic antioxidative defense (AD) and possible nitric oxide (NO) role in AD organization of adult rats receiving l-arginine.HCl (2.25%) or N(omega)-nitro-l-arginine methyl ester (L-NAME.HCl, 0.01%) as drinking liquids and maintained at room (22+/-1 degrees C) or low (4+/-1 degrees C) temperature for 45 days were studied. For that purpose, copper, zinc- and manganese superoxide dismutase (CuZnSOD, MnSOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) and glutathione reductase (GR) activities were determined. Cold-induced decrease of CuZnSOD was inhibited with L-NAME, while l-arginine produced the same effect as cold in both supplemented groups. Cold acclimation elevated GSH-Px activity. l-Arginine and L-NAME expressed no effect on GSH-Px in rats kept at room temperature. L-NAME additionally elevated cold-induced GSH-Px activity, l-arginine expressing a similar trend. Cold-induced increase in GST activity was inhibited by L-NAME, while l-arginine inhibited this enzyme in both supplemented groups. Cold acclimation increased GR activity in control and L-NAME-treated group and l-arginine expressed a similar trend. Neither of the treatments affected MnSOD and CAT activities. Cold-induced changes of pancreatic AD were additionally affected by the alterations in l-arginine-NO-producing pathway. Some AD changes in the same direction with l-arginine or L-NAME point to the complexity of nitrogen compounds metabolism and function, accompanied by tissue-specific response.
Vasilijević
Ana
A
Department of Physiology, Institute for Biological Research, Sinisa Stanković, University of Belgrade, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia.
Buzadzić
Biljana
B
Korać
Aleksandra
A
Petrović
Vesna
V
Janković
Aleksandra
A
Mićunović
Ksenija
K
Korać
Bato
B
D000064:Acclimatization; D000818:Animals; D002374:Catalase / Q000378:metabolism; D003080:Cold Temperature; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D010179:Pancreas / Q000201:enzymology*; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism
D009569:Nitric Oxide; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase; D019331:NG-Nitroarginine Methyl Ester