Two types of putative preneoplastic lesions identified by hexosaminidase activity in whole-mounts of colons from F344 rats treated with carcinogen.
Previous studies identified as putative preneoplastic lesions 1) enzyme-altered foci in sections of methacrylate-embedded colon and 2) aberrant crypts in methylene blue-stained unembedded (whole-mount) colon and established that aberrant crypts embedded in methacrylate had enzyme alterations. We have now studied histochemically demonstrable hexosaminidase activity in unembedded or whole-mount preparations of colons from carcinogen-treated rats. These preparations have revealed two populations of crypts that are enzyme-altered: those that are morphologically altered or aberrant and those that are morphologically normal. Both populations can be quantified rigorously in less than an hour with whole-mount preparations reacted for hexosaminidase. The demonstration of phenotypic characteristics with histochemical techniques in whole-mount preparations should have wide applicability to functional studies in many normal and diseased tissues.
Institute of Pathology, Case Western Reserve University, Cleveland, OH 44106.
T P
TP
Pretlow
M A
MA
O'Riordan
K M
KM
Spancake
T G
TG
Pretlow
D000818:Animals; D001397:Azoxymethane; D002273:Carcinogens; D004796:Clinical Enzyme Tests; D003106:Colon / Q000201:enzymology* / Q000473:pathology / Q000648:ultrastructure; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000175:diagnosis*; D006596:Hexosaminidases / Q000378:metabolism*; D007279:Injections, Subcutaneous; D008297:Male; D008871:Microvilli / Q000648:ultrastructure; D010833:Phytic Acid / Q000494:pharmacology; D011230:Precancerous Conditions / Q000139:chemically induced / Q000175:diagnosis*; D051381:Rats; D011916:Rats, Inbred F344
D002273:Carcinogens; D010833:Phytic Acid; D006596:Hexosaminidases; D001397:Azoxymethane