Pyroja, S; Paulose,C S(Department of Biotechnology, Faculty of Science, April , 2002)
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Abstract:
The work is an attempt to understand the role of 5-HT, 5-HT1A and 5-HT2C receptors in the regulation of liver cell proliferation using in vivo and in vitro models. The work also focuses on the brain serotonergic changes associated with hapatocyte proliferation and apoptosis to delineate its regulatory function. The investigation of mechanisms involving different models of hepatocyte proliferation contributes to our knowledge about serotonergic regulation of cell growth, apoptosis and carcinogenesis of liver. The study reveals that the alteration of the 5-HT1A and 5-HT2C receptor function and gene expression in the brain stem, cerebral cortex and hypothalamus play an important role in the sympathetic regulation of cell proliferation, neoplastic transformation and apoptosis. The functional balance between 5-HT1A and 5-HT2C receptor plays an important role in regulating hepatocyte proliferation, neoplastic transformation and hepatic apoptosis. The regulatory role of 5-HT1A and 5-HT2C receptor during neoplastic transformation and apoptosis could lead to possible therapeutic intervention in the treatment of cancers and have immense clinical importance.
Waliaula Mola,P; Sudha, B; Paulose,C S(Department of Biotechnolgy, November , 1996)
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Abstract:
The effect of insulin on cell proliferation in vivo has been studied in hepatectomised
streptozotocin- diabetic rats. The extent of cell proliferation in sham and hepatectomized- control,
diabetic and insulin treated rats were monitored by determining DNA content and [3H]thymidine
incorporation into DNA. The kinetic parameters of thymidine kinase a regulatory enzyme for
DNA synthesis was also studied in these groups. The rate of DNA synthesis in liver of
streptozotocin -diabetic rats was significantly higher 24 hrs post-hepatectomy compared to
control and insulin treated diabetic groups. Kinetic studies of thymidine kinase revealed that there
was no change in the Michaelis -Menten constant (Km) whereas maximum velocity (Vmax) was
elevated in the diabetic hepatectomized groups compared to control and insulin treated
hepatectomized groups. Thus our study elucidates the role of insulin in thymidine kinase activity
and DNA synthesis.