Kinetic Parameters of Thymidine Kinase and DNA Synthesis During Liver Regeneration: Role Ofthyroid Hormones

Dyuthi/Manakin Repository

Kinetic Parameters of Thymidine Kinase and DNA Synthesis During Liver Regeneration: Role Ofthyroid Hormones

Show full item record

Title: Kinetic Parameters of Thymidine Kinase and DNA Synthesis During Liver Regeneration: Role Ofthyroid Hormones
Author: Tessy,Maliekal T; Sudha,B; Paulose,C S
Abstract: The role of thyroid hormones in DNA synthesis and in the activity of Thymidille kinase (TK), a key regulatory enzyme of DNA synthesis was studied in proliferating hepatocytes in vivo. Liver regeneration after partial hepatectomy was used as a model for controlled cell division in rats having different thyroid status - euthyroid, hypothyroid and 3,3',5'-triiodo-L-thyronine (T))-heated hypothyroid. Partial hepatectomy caused a significant elevation of DNA synthesis (p<0.01) in all the three groups compared to their sham-operated counterparts. Hypothyroid liepatectomised animals showed significantly lower (p<0.01) level of DNA synthesis than euthyroid hepatectomised animals. A single subcutaneous close of 1'3 to hypothyroid shamoperated animals resulted in a significant increase (p<0.01) of DNA synthesis in the intact liver. 17tis was comparable to the level of DNA synthesis occurring in regenerating liver of euthyroid animals. In hypothyroid hepatectomised animals, "1'3 showed an additive effect on l)NA synthesis and this group exhibited maximum level of DNA synthesis (p<0.0I ). Studies of the kinetic parameters of TK show that the Michelis-Menten constant, (K111) of TK for thymidine was altered by the thyroid status. K11 increased significantly (p<0.01) in untreated hypothyroid animals when compared to the euthyroid rats. '13 treatment of hypothyroid animals reversed this effect and this group showed the lowest value for K111 (p<0.01). Thus our results indicate that thyroid hormones can influence DNA synthesis during liver regeneration and they may regulate the activity of enzymes such as 17rymidine kinase which are important for DNA synthesis and hence cell division.
URI: http://dyuthi.cusat.ac.in/purl/538
Date: 1997-02-14


Files in this item

Files Size Format View Description
Tessy T Maliekal and others(19970feb.PDF 5.440Mb PDF View/Open pdf

This item appears in the following Collection(s)

Show full item record

Search Dyuthi


Advanced Search

Browse

My Account