Cerium-based histochemical demonstration of oxidative stress in taurocholate-induced acute pancreatitis in rats. A confocal laser scanning microscopic study.
Direct in vivo histological detection of oxygen-derived free radicals (OFRs) in inflammatory conditions is not fully resolved. We report an application of cerium histochemistry (in which capture of OFRs by Ce atoms results in laser-reflectant cerium-perhydroxide precipitates) combined with reflectance confocal laser scanning microscopy (CLSM) to demonstrate the evolution of oxidative stress in taurocholate-induced acute pancreatitis (AP) in rats. Animals were perfused with CeCl(3) in vivo and cryostat sections of pancreata were studied by CLSM. Vascular endothelium was immunolabeled for PECAM-1. OFR production by isolated polymorphonuclear leukocytes (PMNs) incubated in vitro with CeCl(3) was quantified by image analysis. In the pancreas, strong OFR-derived cerium reflectance signals were seen in acinar cells at 1-2 hr, capillaries and small venules were frequently engorged by cerium precipitates, and adherent PMNs presented weak intracellular reflectance signals. At 8-24 hr, acinar cell OFR production decreased, whereas adherent/transmigrated PMNs displayed abundant intra- and pericellular reflectance. PECAM-1 expression was unchanged. PMNs from ascites or blood showed significant (p<0.01) time-dependent OFR production, plateauing from 2 hr. The modified cerium capture/CLSM method allows the co-demonstration of in vivo oxidative stress and cellular structures labeled with fluorescent markers. In vivo oxidative stress was shown histologically for the first time in experimental AP.
Telek
G
G
INSERM U410, Faculté de Médecine Xavier Bichat, Université Paris 7, Paris, France.
Scoazec
J Y
JY
Chariot
J
J
Ducroc
R
R
Feldmann
G
G
Roz
C
C
D000208:Acute Disease; D000818:Animals; D002563:Cerium / Q000378:metabolism*; D006651:Histocytochemistry / Q000379:methods*; D006878:Hydroxides; D007150:Immunohistochemistry; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism; D008297:Male; D018613:Microscopy, Confocal; D018384:Oxidative Stress; D010195:Pancreatitis / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D010545:Peroxides / Q000378:metabolism*; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013656:Taurocholic Acid; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors
D006878:Hydroxides; D010545:Peroxides; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D017382:Reactive Oxygen Species; D002563:Cerium; D013656:Taurocholic Acid; C048873:cerium hydroxide; D013755:Tetradecanoylphorbol Acetate