Melanocyte-Stimulating Activity in a Transplantable Mouse Pituitary Tumor1
| Autor: | R. A. Huseby, I. I. Geschwind |
|---|---|
| Rok vydání: | 1966 |
| Předmět: | |
| Zdroj: | Endocrinology. 79:97-105 |
| ISSN: | 1945-7170 0013-7227 |
| DOI: | 10.1210/endo-79-1-97 |
| Popis: | Levels of melanocyte-stimulating activity were determined in the circulation and in the tumors of mice bearing a transplantable pituitary tumor which produced darkening of the coat color. An average concentration of 5.1 (±0.6) X104 U/mg dry weight was found for 8 tumors. The level of activity in the circulation (C.L.A.) was followed as a function of time following transplantation of the tumor and was correlated with the change in the reflectance of the coat and the growth of the tumor. An average C.L.A. of approximately 6 U per ml per mg tumor wet weight was found. Changes in coat color became apparent while the tumor was still quite small and the C.L.A. was low (less than 100 U/ml); however, maximal darkening occurred at a time when the C.L.A. was approximately 1000 U/ml or more. The half-lives of the endogenous circulating activity in the mouse and of exogenous α-MSH in the rat were both found to be approximately 1.7 min. A secretion rate of approximately 1.5 X104 U per day per mg tumor wet weight was c... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|