Inhibitory effect of platelet-activating factor (PAF) on luteinizing hormone-releasing hormone and somatostatin release from rat median eminence in vitro correlated with the characterization of specific PAF receptor sites in rat hypothalamus.
Inhibitory effect of platelet-activating factor (PAF) on luteinizing hormone-releasing hormone and somatostatin release from rat median eminence in vitro correlated with the characterization of specific PAF receptor sites in rat hypothalamus.
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体外血小板活化因子（PAF）对大鼠正中隆起促黄体生成素释放激素和生长抑素释放的抑制作用与大鼠下丘脑中特定PAF受体位点的特征相关。
DOI：
10.1210/endo-123-1-72
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发表时间：
1988
期刊：
影响因子：
4.8
通讯作者：
F. Dray
中科院分区：
文献类型：
--
作者：
M. Junier;C. Tiberghien;C. Rougeot;V. Fafeur;F. Dray
血小板活化因子（PAF）具有广泛的生物学活性，包括刺激各种细胞类型的分泌过程。然而，关于其对脑神经肽释放的可能影响知之甚少。在本研究中，我们研究了PAF对成年雄性大鼠下丘脑释放三种激素的影响，并确定了大鼠下丘脑膜中存在特异性PAF结合位点。PAF减少正中隆起LHRH和生长抑素（SRIF）的释放，在10（-14）M时对两种神经肽的抑制作用最大，而GRF的释放没有明显改变。此外，PAF强烈地抵消了Ca 2+离子载体A23187刺激的LHRH和SRIF从正中隆起和内侧基底下丘脑的释放（大于50%的抑制）。这些结果表明，PAF行动的Ca 2+依赖性事件的参与。这种抑制作用是专门施加在下丘脑的网站，因为PAF未能抑制LH和GH释放垂体前叶。[~ 3 H]PAF与大鼠下丘脑膜具有特异性、可逆性和饱和性结合，并发现两类结合位点。每种结合类别的亲和力（KD）分别为2.14 +/- 0.32 nM和61.63 +/- 16.4 nM，每种结合类别的相应最大数量分别为25.41 +/- 3.2 fmol/mg蛋白和146.2 +/- 47.5 fmol/mg蛋白。在相同条件下，使用大鼠垂体膜未观察到特异性结合。PAF类似物对这些结合位点的特异性与其改变LHRH和SRIF释放的相对有效性密切相关（效力顺序：L-652，731，海风藤酮大于BN 52021，大于Lyso-PAF）。这些数据表明，下丘脑中鉴定的结合位点具有特定PAF受体的预期特征，并且PAF对神经肽释放的影响是一个受体介导的过程。
Platelet-activating factor (PAF) exhibits a wide range of biological activities, including the stimulation of secretory processes in various cell types. However, little is known regarding its possible influence on the release of brain neuropeptides. In the present study we have examined the effect of PAF on the release of three hypothalamic releasing hormones in adult male rats, and have characterized the presence of specific PAF binding sites in rat hypothalamic membranes. PAF decreased LHRH and somatostatin (SRIF) release from the median eminence with a maximal inhibition at 10(-14) M for both neuropeptides, whereas GRF release was not significantly altered. Moreover, PAF strongly counteracted the Ca2+ ionophore A 23187-stimulated release of LHRH and SRIF from median eminence and medial basal hypothalamus (greater than 50% inhibition). These results suggest an involvement of Ca2+ dependent events in PAF action. This inhibitory effect was specifically exerted at a hypothalamic site because PAF failed to depress LH and GH release from the anterior pituitary. A specific, reversible and saturable binding of [3H]PAF to membrane preparations of rat hypothalamus was demonstrated and two classes of binding sites were characterized. The affinity (KD) of each binding class was 2.14 +/- 0.32 nM and 61.63 +/- 16.4 nM, respectively, and the corresponding maximal number of each binding class was 25.41 +/- 3.2 fmol/mg protein and 146.2 +/- 47.5 fmol/mg protein. In the same conditions no specific binding was observed using rat pituitary membranes. The specificity of PAF analogs for these binding sites was well correlated to their relative effectiveness in altering LHRH and SRIF release (order of potency: L-652,731, kadsurenone greater than BN 52021 greater than Lyso-PAF). These data suggest that the binding sites identified in the hypothalamus have the characteristics expected of a specific PAF receptor and that PAF effect on neuropeptides release is a receptor-mediated process.
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烷基乙酰甘油与溶血 PAF 作为 PAF 生物合成中的前体以及花生四烯酸在 PAF 代谢中的作用。
DOI：
10.1016/0031-6989(86)90036-6
发表时间：
1986
期刊：
Pharmacological research communications
影响因子：
--
作者：
Snyder,F;Blank,ML;Johnson,D;Lee,TC;Malone,B;Robinson,M;Woodard,DS
通讯作者：
Woodard,DS
DOI：
10.1172/jci110108
发表时间：
1981
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
McManus,LM;Hanahan,DJ;Pinckard,RN
通讯作者：
Pinckard,RN
下丘脑前列腺素 E2 的释放取决于细胞外 Ca2 的可用性：与 LHRH 释放的关系。
影响因子：
4.1
作者：
Ojeda,SR;Negro-Vilar,A
通讯作者：
Negro-Vilar,A
1-烷基-2-乙酰基-sn-甘油-3-磷酸胆碱（一种降血压和血小板活化脂质）的特异性乙酰水解酶。
DOI：
--
发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Blank,ML;Lee,T;Fitzgerald,V;Snyder,F
通讯作者：
Snyder,F
兔血小板中 1-烷基-2-乙酰基-sn-甘油-3-磷酸胆碱（血小板激活因子）对钙吸收的刺激：可能涉及脂氧合酶途径。
影响因子：
3.9
作者：
Lee,TC;Malone,B;Snyder,F
通讯作者：
Snyder,F