Temperature-dependent Elaboration of Collagenase by the Renal Adenocarcinoma of the Leopard Frog, Rana p/p/ens1
نویسندگان
چکیده
Naturally occurring renal adenocarcinoma in North American leopard frogs, Rana pipiens, metastasize frequently (77%) when these ectothermic animals are kept in a warm environment but not when they are kept cold. We have found that expiants of these tumors secrete collagenase, an enzyme capable of dis solving connective tissue fibers and found previously to be closely correlated with metastatic colony-forming capability of murine mammary tumors, and that the amount released sequen tially rises and falls as the ambient temperature is shifted be tween metastasis-permissive and -inhibitory levels. In contrast, normal frog renal tissue has low collagenase output, unaffected by temperature changes.
منابع مشابه
Temperature-dependent elaboration of collagenase by the renal adenocarcinoma of the leopard frog, Rana pipiens.
Naturally occurring renal adenocarcinoma in North American leopard frogs, Rana pipiens, metastasize frequently (77%) when these ectothermic animals are kept in a warm environment but not when they are kept cold. We have found that explants of these tumors secrete collagenase, an enzyme capable of dissolving connective tissue fibers and found previously to be closely correlated with metastatic c...
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