RESUMO
Changes in blood glucose in response to glucagon and epinephrine administration, in rats bearing Yoshida solid sarcoma and Walker-256 carcinosarcoma have been studied, and in rats carrying Yoshida tumor which had received previously intraperitoneal glucose. The response to glucagon by tumor-bearing rats follows the control pattern but at a lower level of blood glucose. Rats which had received glucose before glucagon administration responded to this hormone as the control animals. These results indicate that glycogen metabolism in the host liver is not diturbed by the presence of the tumor.
Assuntos
Glicemia/metabolismo , Carcinoma 256 de Walker/sangue , Epinefrina/farmacologia , Glucagon/farmacologia , Sarcoma de Yoshida/sangue , Animais , Glucose/farmacologia , Glicogênio Hepático/metabolismo , Masculino , Ratos , Inanição/sangueRESUMO
The etiology of anemia in cancer is not fully understood. A possible cause of the anemia of tumor-bearing animals could be a decreased activity in the enzymes of the heme-pathway. We report the enzyme activity of porphobilinogen-synthetase in the liver of Yoshida sarcoma-bearing rats. PBG-synthetase activity in the whole liver, is higher in tumor-bearing rats than in controls, although the enzyme activity by a gram of wet liver is decreased. Hence PBG-synthetase activity is not a limiting factor in the biosynthesis of heme in tumor-bearing animals.
