Hormonal Control of Net Glucose-Stimulated Lipogenesis During Transition From
Brown to White Adipose Tissue
in the Goat
J. Škarda
Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech
Republic, Prague, Czech Republic
Received June 15, 1999
Accepted October 10, 1999
Summary
Perinatal (1-2 days of age) and one-month-old (24-32 days of
age) male goats were used to investigate the effect of age and long-term culture
(24 h) of perirenal and omental adipose explants in the presence of insulin, cortisol and bovine somatotropin (alone or in different combinations) on net
glucose-stimulated lipogenesis (NGSL, i.e. the rate of lipogenesis in the
presence of glucose minus the rate of lipogenesis in the absence of glucose) in
the absence and in the presence of catecholamines in acute incubations (2 h).
Mean values of NGSL in both freshly prepared and cultured explants were
consistently lower in perinatal than in one-month-old goats. Cortisol alone
decreased and combinations of insulin plus cortisol increased NGSL in perirenal
explants of one-month-old animals. When perirenal explants from these
one-month-old goats were cultured in the presence of insulin plus cortisol plus
bovine somatotropin, the rates of lipogenesis were lower than those in cultures
with insulin plus cortisol. No such effects of these hormones were noted in omental explants of both perinatal and one-month-old animals. In freshly
prepared perirenal and omental explants, the rates of NGSL were inhibited by isoprenaline in tissues of both groups of animals and by noradrenaline in
omental tissues of animals of the older group only. The mean values of NGSL in
cultured explants of perinatal animals were not affected by noradrenaline.
Isoprenaline inhibited NGSL in omental but not in perirenal tissue. In older
animals the rates of NGSL were decreased by both noradrenaline and isoprenaline
in perirenal and omental adipose tissues. Isoprenaline was more effective than noradrenaline in perirenal adipose tissue.
Key words
Goat · Ontogenesis ·
Adipose tissue · Lipogenesis ·
Hormones
Reprint requests
J. Škarda, Institute of Animal Physiology and Genetics, 104
00 Prague 10-Uhříněves, Czech Republic. e-mail: skarda@iapg.cas.cz
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