Inhibition of cyclic AMP production by alpha 2-adrenoceptor stimulation in the guinea-pig spinal cord slices.
Inhibition of cyclic AMP production by alpha 2-adrenoceptor stimulation in the guinea-pig spinal cord slices.
复制标题
豚鼠脊髓切片中 α2-肾上腺素受体刺激抑制环 AMP 的产生。
DOI：
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发表时间：
1988
期刊：
影响因子：
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通讯作者：
J. Wikberg
中科院分区：
文献类型：
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作者：
S. Uhlén;J. Wikberg
用3h -腺嘌呤预孵育豚鼠脊髓切片，0.3 ~ 30 μ m福斯克林诱导3H-cAMP含量呈剂量依赖性增加，最大增幅约为8倍。选择性α 2-肾上腺素能激动剂UK-14,304（10微米）使基础和forskolin刺激的3H-cAMP水平降低18-32%。在3微米的福斯克林刺激下，uk - 14304对脊髓切片cAMP产生影响的剂量反应曲线显示IC50为37 nM，最大抑制作用为27%。许多其他α 2-肾上腺素能激动剂（可乐定、胍法辛、B-HT 920和B-HT 933）也抑制福斯克林刺激的3H-cAMP的产生；可乐定和胍法辛与uk - 14304的抑制作用基本相当，但其最大抑制作用仅为6-7%。B-HT 920和B-HT 933的抑制作用较弱，最大抑制作用约为16-21%。0.3 μ m育亨宾作用下，uk - 14304对福斯克林刺激的cAMP产生的抑制作用的剂量响应曲线向右移动了近50倍。0.3微米的吡唑嗪对uk - 14304剂量响应曲线无影响。由此可见，α 2-肾上腺素能受体刺激介导了豚鼠脊髓cAMP生成的抑制。
In spinal cord slices isolated from guinea-pig and preincubated with 3H-adenine, 0.3-30 microM forskolin induced a dose-dependent increase in the content of 3H-cAMP, the maximal increase being about 8-fold. The selective alpha 2-adrenergic agonist UK-14,304 (10 microM) reduced both the basal and the forskolin stimulated levels of 3H-cAMP by 18-32%. Dose response curves of the effect of UK-14,304 on cAMP production in the spinal cord slices, stimulated with 3 microM forskolin, showed an IC50 of 37 nM and a maximally inhibitory effect of 27%. A number of other alpha 2-adrenergic agonist (clonidine, guanfacine, B-HT 920 and B-HT 933) also inhibited the forskolin stimulated 3H-cAMP production; clonidine and guanfacine being almost equipotent with UK-14,304, but their maximal inhibitory effects being only about 6-7%. B-HT 920 and B-HT 933 were less potent and their maximal inhibitory effects about 16-21%. The dose response curve of UK-14,304 on inhibition of forskolin stimulated cAMP production was shifted almost 50-fold to the right by 0.3 microM yohimbine. Prazosin (0.3 microM) did not affect the UK-14,304 dose response curve. It is concluded that alpha 2-adrenoceptor stimulation mediates inhibition of cAMP production in the guinea-pig spinal cord.