| Autor: |
Maddaiah, Vaddanahally T, Rezvani, Iraj, Chen, Shang Y, Collipp, Platon J |
| Zdroj: |
Pediatric Research; September 1970, Vol. 4 Issue: 5 p457-458, 2p |
| Abstrakt: |
To understand the early molecular events that lead to some of the effets of growth hormone on liver, a dose of 3H-HGH (18 × 106cpm, 60 µg) was give i.v. to hypophysectomized rats. After the injection, livers were homogenized and fractionated by centrifugation. Specific activity (cpm/mg protein) and total radioactivity expressed as percent of that in the homogenate were estimated (table). 3H-HGH in the homogenate was estimated by precipitation with TCA, and with Na2SO4as 3H-HGH antibody complex with and without unlabeled hormone. Up tp 10 min most homogenate was antigenically and 3H-HGH in the homogenate was antigenically similar to the injected dose. In contrast, when 3H-HGH was added in vitro before homogenization most radioactivity (77%) appeared in the cytoplasm and the rest distributed almost eqully among the other fractions. These results indicate (1) the early rapid uptake by the particulate fractions may be of functional significance and the important initial binding sites may be mitochondria and microsomes; (2) the movement of 3H-GH in liver cell may be from the microsomal and mitochondrial fractions into cytoplasm; (3) after 10 min 3H-HGH is degraded or deacetylated. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
