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Abstract

Embryo transfer technology has not been very successful as far as herd improvement in water buffaloes is concerned. Among many reasons for this unimpressive success in water buffaloes unlike in regular cattle and other farm animals, one could be the non-use of homologous Gonadotropins for induction of super ovulation. On the other hand, the use of the long acting Pregnant Mare Serum Gonadotropin (PMSG) has its own attendant problem like possessing undesirable level of Luteinizing Hormonal (LH) activity in PMSG. Buffalo LH (buLH), Prolactin (PRL), Follicle Stimulating Hormone (FSH), Growth Hormone (GH) and Thyroid Stimulating Hormone have been purified from freshly frozen pituitaries and characterized. Unlike in the case of buLH, buGH and buPRL where the yield is very good, the yield is low (2-3 mg/kg) in the case of buTSH and buFSH. Thus biochemical methods do not yield sufficient quantities buFSH/buTSH to undertake field trials for the induction of super ovulation. Biologically active recombinant buPRL, buLH, buTSH and buFSH have been successfully produced. These protocols can be easily scaled up to initiate field trials. The biological activity of bacterially produced buPRL was determined by its ability to stimulate cell division in rat Nb2 lymphoma cell line in vitro. The biological activity of recombinant buTSH was demonstrated by measuring its stimulatory effect on cAMP levels in appropriate target tissue and cells in vitro. The dual activity (LH- like and TSH-like) of native human chorionic Gonadotropin (hCG) was demonstrated by the same parameter. The biological activity of recombinant buFSH was demonstrated in rats by the classical Steelman-Pohley bioassay in vivo. The dual activity of PMSG (LH-like and FSH-like) in heterologous animal species like rat has been shown to include a common biochemical effect of stimulating the ovarian L-Gulonic acid dehydrogenase (L-GuDH) activity. The latter is an important enzyme in the non-phorphorylated sugar metabolism including formation of L-Xylulose and L-Ascorbic acid. The significance of these observations has been discussed.

Biography

Kambadur Muralidhar is a distinguised Biologist. He obtained his BSc and MSc from Osmania University, Hyderabad. He started his research work under L K Ramachandran, at Osmania University in the summer of 1969. He obtained his PhD from IISc, Bangalore in 1976 working under N R Moudgal. His PhD work, demonstrating that beta subunit of Luteinizing Hormone can bind ovarian receptors fetched him the Prof KV Giri Memorial Gold medal for the best PhD thesis of the year. He was selected for the first Lecturership in the School of Life Sciences at the newly founded Central University of Hyderabad in August 1976. During 1979-1981, he was a Research Associate in the Department of Cell and Molecular Biology at SUNY, Buffalo, New York, USA with O P Bahl. His work led to the development of the most sensitive RIA for HCG, a pregnancy hormone. He also demonstrated the immuno-contraceptive vaccine potential of DS5-hCG beta subunit. He joined the University of Delhi in 1983 as Reader in Biochemistry and became a Professor in Endocrinology in 1988. He was Chairman of the Department during 2001-2004.

Email: kambadur2014@southasianuniversity.org