Pygmy mouse fibroblasts in tissue culture: evaluation of multiplication stimulating activity (MSA) receptors and growth responses to MSA
| Autor: | Nissley Sp, White Rm, August Gp |
|---|---|
| Rok vydání: | 1984 |
| Předmět: |
medicine.medical_specialty
animal structures Endocrinology Diabetes and Metabolism medicine.medical_treatment Clinical Biochemistry Receptors Cell Surface Biology Biochemistry Tissue culture Mice Endocrinology Insulin-Like Growth Factor II Somatomedins Internal medicine medicine Animals Fibroblast Receptor Growth Substances Cells Cultured Growth Disorders Platelet-Derived Growth Factor Cell growth Growth factor Biochemistry (medical) Receptors Somatomedin General Medicine DNA Fibroblasts Somatomedin Growth hormone treatment medicine.anatomical_structure Cell culture Peptides hormones hormone substitutes and hormone antagonists Cell Division Thymidine |
| Zdroj: | Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme. 16(8) |
| ISSN: | 0018-5043 |
| Popis: | The pygmy mouse has been proposed as a model for growth hormone resistance; it has normal serum somatomedin levels and does not respond to growth hormone treatment. In order to determine if the growth impairment is caused by a defect in somatomedin binding or in postreceptor action of somatomedin we compared fibroblasts derived from pygmy mice with those from normal appearing littermates. Using multiplication-stimulating activity (MSA) as a model somatomedin we found a normal Ka of binding to the cell surface MSA receptor but a significantly increased number of MSA receptors on the fibroblasts derived from pygmy mice. Studies of thymidine incorporation into DNA failed to demonstrate a difference between pygmy and normal fibroblasts in their responses to MSA alone, but there was a significantly greater thymidine incorporation into the DNA of normal fibroblasts when both competence factor (platelet-derived growth factor) and progression factors (somatomedins and growth hormone deficient platelet-poor plasma) were present in the test medium. On the other hand, cell proliferation studies did not demonstrate a consistent difference in the growth rate of normal versus pygmy fibroblasts. The data support the conclusion that the imparied growth of the pygmy mouse in vivo may be caused by factors which lie outside of the growth hormone-somatomedin pathway. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|