Freshly prepared and cultured perirenal and omental adipose tissue explants
were used to investigate the effect of age and hormones on lipogenesis in
young goats. Perinatal (1-2 days of age) and older (24- 32 days of age) mal
e goats were used. Adipose explants were cultured (24 h) in the presence of
insulin, cortisol and recombinant bovine growth hormone (bST) and subseque
ntly incubated (2 h) in a glucose-free buffer containing (C-14)-acetate in
the presence or absence of noradrenaline (Ne) and isoprenaline (Iso) to mea
sure tissue lipogenic responses to hormones added to the culture medium and
to measure the responsiveness to catecholamines. Inclusion of hormones in
the culture medium did not change lipogenesis during subsequent acute incub
ation in glucose-free buffer in both perirenal and omental adipose tissue f
rom perinatal goats. On the other hand, in perirenal explants from older an
imals, insulin alone or insulin plus cortisol increased (P < 0.05) and cort
isol alone decreased (P < 0.05) the late of fatty acid synthesis. When peri
renal explants were cultured in the presence of insulin plus cortisol plus
bST, the rates of lipogeneses were lower (P < 0.05) than those in cultures
with insulin plus cortisol. A similar pattern of the effects of hormones on
the rates of fatty acid synthesis was also seen in omental explants; howev
er, these effects were not significant. In vitro rates of lipogeneses were
decreased (P < 0.05) by Ne but not Iso in freshly prepared omental explants
of both perinatal and older animals and in freshly prepared perirenal expl
ants of older animals. In cultured perirenal er;plants of both perinatal an
d older animals the mean values of lipogenesis were decreased (P < 0.05) by
both Ne and Iso. However, in cultured omental explants both catecholamines
were effective (P < 0.05) in older but not in perinatal animals.