title: Caspase activation during spontaneous and radiation-induced apoptosis in the murine intestine.
abstract: The aim of this study was to characterize the activation of caspase-3 along the crypt/villus axis in the normal and irradiated intestine and to compare active caspase-3 expression with existing apoptosis detection techniques. Small and large intestine were removed from mice at various time points after exposure to 8 Gy gamma-radiation. Positive apoptotic cells stained with an antibody against active caspase-3, haematoxylin and eosin (H&E) or TUNEL were scored in histological sections of small and large intestinal crypts and villi. In the control intestine, active caspase-3 expression was rarely observed; however, expression was markedly increased following exposure to radiation and was predominantly confined to apoptotic bodies. Measurement of apoptosis in intestinal crypts using active caspase-3 expression gave similar results to apoptosis detected from H&E-stained sections. In the normal villus, active caspase-3 expression was observed infrequently and did not significantly increase following radiation, consistent with a lack of apoptotic body formation from H&E sections. This study indicates that caspase-3 is activated in intestinal crypts but not in villi following gamma-radiation. Active caspase-3 detection compared favourably with existing immunological techniques, suggesting that it is a suitable alternative method for apoptosis quantification.
authors.affiliation: Department of Medicine, University of Liverpool, UCD Duncan Building, Daulby Street, Liverpool, L69 3GA, UK.
authors.forename: E
authors.initials: E
authors.lastname: Marshman
authors.forename: P D
authors.initials: PD
authors.lastname: Ottewell
authors.forename: C S
authors.initials: CS
authors.lastname: Potten
authors.forename: A J
authors.initials: AJ
authors.lastname: Watson
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D017209:Apoptosis; D053148:Caspase 3; D020169:Caspases / Q000276:immunology / Q000378:metabolism*; D003106:Colon / Q000201:enzymology / Q000528:radiation effects; D004789:Enzyme Activation; D004801:Eosine Yellowish-(YS); D004848:Epithelium / Q000201:enzymology / Q000528:radiation effects; D006416:Hematoxylin; D007150:Immunohistochemistry / Q000379:methods; D020287:In Situ Nick-End Labeling / Q000379:methods; D007421:Intestine, Small / Q000201:enzymology / Q000528:radiation effects; D007422:Intestines / Q000201:enzymology* / Q000528:radiation effects; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D013194:Staining and Labeling
chemical_list: D000911:Antibodies, Monoclonal; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin