ENHANCEMENT OF DNA-POLYMERASE BETA-ACTIVITY IN THE PITUITARY-GLAND BYHORMONAL FEEDBACK

Authors
NAGASAKA A YOSHIDA S MASUNAGA R KATO S KOTAKE M NAKAI A KAWABE T TSUJIMURA T INAGAKI A IWASE K
Citation
A. Nagasaka et al., ENHANCEMENT OF DNA-POLYMERASE BETA-ACTIVITY IN THE PITUITARY-GLAND BYHORMONAL FEEDBACK, Hormone and Metabolic Research, 25(8), 1993, pp. 403-406
Citations number
10
Categorie Soggetti
Endocrynology & Metabolism
Journal title
Hormone and Metabolic Research → ACNP
ISSN journal
00185043
Volume
25
Issue
8
Year of publication
1993
Pages
403 - 406
Database
ISI
SICI code
0018-5043(1993)25:8<403:EODBIT>2.0.ZU;2-Y
Abstract
The activity of DNA polymerase beta (beta-enzyme) in bovine and rat pi tuitary glands was remarkably higher in the anterior than in the poste rior lobe. In sucrose gradient centrifugation, the activity in the ant erior lobe of the bovine pituitary gland appeared at the sedimentation constant, 3.3 S, while that of rat pituitary gland appeared at 3.3 S, 7.3 S and 12 S, respectively. The activity in each fraction increased in the anterior lobes of rat pituitaries that were stimulated to rele ase TSH by decreased thyroid hormone levels induced by an antithyroid drug. These results suggest that the activity of the beta-enzyme is hi gh in the cells of the anterior lobe which are hyperfunctioned to prod uce pituitary thyreotrophic hormone and may be controlled by hormonal feedback regulation.