Dual effects of the lichen glucan PB-2, extracted from Flavoparmelia baltimorensis, on the induction of long-term potentiation in the dentate gyrus of the anesthetized rat:: possible mediation via adrenaline β- and interleukin-1 receptors
Dual effects of the lichen glucan PB-2, extracted from Flavoparmelia baltimorensis, on the induction of long-term potentiation in the dentate gyrus of the anesthetized rat:: possible mediation via adrenaline β- and interleukin-1 receptors
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DOI：
10.1016/j.brainres.2004.11.012
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发表时间：
2005-01-25
期刊：
影响因子：
2.9
通讯作者：
Ito, Y
中科院分区：
文献类型：
--
作者：
Edagawa, Y;Sato, F;Ito, Y
我们之前发现，口服或静脉注射从baltimorensis黄衣中提取的多糖PB-2，有助于在体内诱导齿状回（DG）的长期增强（LTP）。本研究探讨了PB-2在麻醉大鼠DG中诱导LTP的作用机制，重点探讨了其对IL-1受体和肾上腺素β受体的作用。静脉注射IL-1ra (10(-9) g/kg)，一种IL-1受体拮抗剂，对DG的基础反应没有影响；然而，这种处理增强了单次静脉注射PB-2 （10(-3) g/kg）诱导的UP的增强。在脑室内注射IL-1ra (10（-15)-10(-11) g）后也观察到这种增强作用。静脉注射il -1 β (3.5 × 10（-15)-3.5 × 10(-9) g/kg）可抑制LTP的诱导，而先前应用IL-1ra可减弱LTP的诱导。这些结果表明，IL-1受体的激活诱导了pb -2处理大鼠LTP的抑制，内源性IL-1 β参与了IL-1受体的激活。静脉输注美托洛尔（7.5 X 10(-6) g），肾上腺素β受体拮抗剂，可减弱静脉注射PB-2诱导的LTP增强。这些结果表明，PB-2对LTP具有增强和抑制两种不同的作用，并且在这些作用的总体平衡中表现出显著的增强作用。(C) 2004 Elsevier B.V.版权所有
We have previously found that oral or intravenous (i.v.) administration of the polysaccharide fraction PB-2, extracted from the lichen Flavoparmelia baltimorensis, facilitated the induction of long-term potentiation (LTP) in the dentate gyrus (DG) in vivo. In this study, the mechanism underlying the effect of PB-2 on the induction of LTP was investigated in the DG of anesthetized rat focusing on the contribution of the interleukin-1 (IL-1) receptor and the adrenaline beta-receptor. An i.v. injection of IL-1ra (10(-9) g/kg), an antagonist of the IL-1 receptor, had no effect on the basal response in the DG; however, this treatment augmented the enhancement of UP induced by a single i.v. injection of PB-2 (10(-3) g/kg). This potentiating effect was also observed following intracerebroventricular (i.c.v.) injection of IL-1ra (10(-15)-10(-11) g). An i.v. injection of IL-1beta (3.5 x 10(-15)-3.5 x 10(-9) g/kg) inhibited the induction of LTP, which was diminished by the previous application of IL-1ra. These results suggest that the activation of the IL-1 receptor induces the suppression of LTP in PB-2-treated rats, and that endogenous IL-1beta contributes to the IL-1 receptor activation. An i.c.v. infusion of metoprolol (7.5 X 10(-6) g), an antagonist of the adrenaline beta(1)-receptor, attenuated the enhancement of LTP induced by an i.v. injection of PB-2. These results suggest that PB-2 has two different effects on the LTP, an enhancing effect and an inhibiting one, and that it exhibited the significant enhancing effect on the LTP as a total balance of these effects. (C) 2004 Elsevier B.V. All rights reserved.