Hu C Y, Novakofski J, Mersmann H J
J Anim Sci. 1987 Apr;64(4):1031-7. doi: 10.2527/jas1987.6441031x.
Compared with adipose tissue from other mammals, porcine adipose tissue has stringent specificity for stimulation of lipolysis by analogs of norepinephrine. This study was to ascertain whether the specificity for control was reflected in the concentration of tissue cyclic AMP (cAMP). Adipose tissue slices were incubated and concentrations of tissue cAMP and free fatty acids (FA) released to the medium were measured. It was necessary to include theophylline in the incubation medium to be able to measure changes in cAMP concentration. Fatty acid release and cAMP production were increased most effectively by the beta-adrenergic agonists; isoproterenol, fenoterol, dobutamine and the mixed alpha- + beta-adrenergic agonist, epinephrine. Isoproterenol-stimulated FA and cAMP production both inhibited by the beta-adrenergic antagonist, propranolol. There was no evidence for alpha 2-adrenergic inhibition of lipolysis in porcine adipose tissue because clonidine (alpha 2-adrenergic agonist) did not lower isoproterenol-induced FA or cAMP levels and phentolamine, an alpha-adrenergic antagonist, did not increase epinephrine-stimulated FA release or cAMP generation. These results imply that the stringent specificity observed for stimulation of swine adipose tissue lipolysis resides in the beta-adrenergic receptor coupled to cAMP production.
与其他哺乳动物的脂肪组织相比，猪脂肪组织对去甲肾上腺素类似物刺激脂肪分解具有严格的特异性。本研究旨在确定这种控制特异性是否反映在组织环磷酸腺苷（cAMP）的浓度上。将脂肪组织切片进行孵育，并测量组织cAMP的浓度以及释放到培养基中的游离脂肪酸（FA）的浓度。为了能够测量cAMP浓度的变化，有必要在孵育培养基中加入茶碱。β-肾上腺素能激动剂异丙肾上腺素、非诺特罗、多巴酚丁胺以及混合的α + β-肾上腺素能激动剂肾上腺素能最有效地增加脂肪酸释放和cAMP生成。异丙肾上腺素刺激的FA和cAMP生成均被β-肾上腺素能拮抗剂普萘洛尔抑制。没有证据表明猪脂肪组织中存在α2-肾上腺素能对脂肪分解的抑制作用，因为可乐定（α2-肾上腺素能激动剂）不会降低异丙肾上腺素诱导的FA或cAMP水平，而α-肾上腺素能拮抗剂酚妥拉明也不会增加肾上腺素刺激的FA释放或cAMP生成。这些结果表明，在刺激猪脂肪组织脂肪分解过程中观察到的严格特异性存在于与cAMP生成相关的β-肾上腺素能受体中。
