Chronic Effects of
Somatotropin Treatment in Vivo and in Vitro on Lipogenic
Activity of Goat Adipose Tissue in a Glucose-Free Buffer During
Acute Incubation
J. ŠKARDA
Institute of Animal Physiology and Genetics,
Academy of Sciences of the Czech Republic, Prague, Czech
Republic
Received July 7, 1998
Accepted September 15, 1998
Summary
Young castrated male goats (n = 8) were used to investigate the
effect of long-term treatment with recombinant methionyl bovine
somatotropin in a sustained release vehicle (bST; 100 mg at
seven-day intervals in a 147-day experiment) and chronic culture
(24 h) of omental adipose tissue in the presence of various
hormones on lipogenic responses to catecholamines during acute
incubation (2 h) in a sodium acetate supplemented glucose-free
buffer. The rate of fatty acid synthesis in freshly-prepared
adipose explants was low and did not differ from those cultured
in the absence of hormones for 24 h. Hormonal combination of
insulin (17 nmol.l-1) plus cortisol (138 nmol.l-1) or insulin
plus recombinant enterokinase linker bST (4.5 nmol.l-1)
increased lipogenesis (P<0.05). Further addition of bST or
cortisol decreased lipogenesis significantly (P<0.05) in the
controls but not significantly in bST-treated animals. Cultured
explants from either control or bST-treated animals showed
significant inhibition of lipogenesis by both norepinephrine (10
m mol.l-1) and isoprenaline (10 m mol.l-1). BST treatment in
vivo did not increase the responsiveness of cultured explants to
norepinephrine in vitro, however, the responsiveness to
isoprenaline(inhibition of lipogenesis) was greater in
bST-treated animals than in the controls.
Key words
Goat - Adipose tissue - Somatotropin - Cortisol - Lipogenesis
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