Effects of orexin on catecholamine synthesis and release in adrenal medulla

食欲素对肾上腺髓质儿茶酚胺合成和释放的影响

• 批准号: 13670855
• 负责人: YANAGIHARA Nobuyuki
• 金额: $ 1.34万
• 依托单位: University of Occupational and Environmental Health
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13670855/
• 关键词: Adrenal medulla; Catecholamine; Obese children; Orexin-A; Orexin receptor 1; Protein kinase C; Synthesis; Tyrosine hydroxylase; オレキシン受容体; 副腎髄質細胞; RT-PCR; オレキシンA; 遊離; ヒト血中オレキシンA濃度

Orexin-A and orexin-B, also known as hypocretin-1 and hypocretin-2, have recently been identified as hypothalamic peptides derived from a precursor, prepro-orexin, in neurons located within and around the lateral and posterior hypothalamus in the rat brain. To determine the role of orexin-A in peripheral metabolic processes, we examined direct effects of orexin-A on catecholamine synthesis and secretion in cultured bovine adrenal medullary cells. 1) Incubation of cells with orexin-A (100 pM) for 20 min caused a small but significant increase in ^<14>C-catecholamine synthesis from [^<14>C] tyrosine, but not from L-3,4-dihydroxyphenyl [3-^<14>C] alanine. Orexin-A (100 pM) potentiated the stimulatory effects of acetylcholine (0.3 mM) ^<14>C-catecholamine synthesis. 2) Orexin-A significantly increased tyrosine hydroxylase activity, which was evident at 1 pM and maximal at 100 pM. 4β-Phorbol-12β-myristate-13α-acetate, an activator of protein kinase C, did not enhance the stimulatory effects of orexin-A on tyrosine hydroxylase activity, while H-7 and staurosporine, inhibitors of protein kinase C, nullified the effects of orexin-A. 3) Orexin-A had little effect on catecholamine secretion from the cells. 4) Orexin receptor 1 (OX_1R) but not orexin receptor 2 (OX_2R) mRNA was detected in bovine adrenal medullary cells by reverse transcriptase-polymerase chain reaction.These findings suggest that orexin-A activates tyrosine hydroxylase and then stimulates catecholamine synthesis, probably via activation of the OX_1R-protein kinase C pathway in adrenal medullary cells. This information helps to understand the biochemical basis of the effect of orexins on metabolic homeostasis in the obesity of adults as well as children.

Orexin-A 和 orexin-B，也称为下丘脑分泌素-1 和下丘脑分泌素-2，最近被鉴定为下丘脑肽，源自大鼠大脑下丘脑外侧和后部内部和周围神经元的前体前体食欲素。为了确定食欲素-A 在外周代谢过程中的作用，我们研究了食欲素-A 对培养牛肾上腺儿茶酚胺合成和分泌的直接影响。 1)用食欲素-A(100pM)孵育细胞20分钟导致来自[^ 14 C]酪氨酸的^ 14 C-儿茶酚胺合成小幅但显着的增加，但不来自L-3。 ，4-二羟基苯基[3-14C]丙氨酸(Orexin-A)(100pM)增强了刺激作用。乙酰胆碱(0.3mM)^ 14 C-儿茶酚胺合成2)食欲素-A显着增加酪氨酸羟化酶活性，这在1pM时明显并且在100pM时最大，4β-佛波醇-12β-肉豆蔻酸-13α-乙酸酯。蛋白激酶C激活剂，不增强食欲素-A对酪氨酸的刺激作用羟化酶活性，而 H-7 和星形孢菌素（蛋白激酶 C 抑制剂）则消除了食欲素 A 的作用。 3) 食欲素 A 对细胞中儿茶酚胺的分泌影响不大。 4) 食欲素受体 1 (OX_1R) 但对食欲素没有影响。通过逆转录酶-聚合酶链反应在牛肾上腺髓质细胞中检测到受体 2 (OX_2R) mRNA。这些发现表明食欲素-A 可能通过激活肾上腺髓质细胞中的 OX_1R-蛋白激酶 C 途径，激活酪氨酸羟化酶，然后刺激儿茶酚胺合成。这一信息有助于了解食欲素对成人肥胖代谢稳态影响的生化基础。以及孩子们。

项目成果

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Asayama K.：“肥胖儿童血清胆固醇酯转移蛋白增加”Obes Res。

Yanagihara N.(分担執筆): "Catecholamine Research : Advances in Behavioral Biology Vol.53"Kluewer Academic/Plenum Publishers, NY. 558 (2002)

Yanagihara N.（撰稿人）：“儿茶酚胺研究：行为生物学进展第 53 卷”Kluewer 学术/Plenum 出版社，纽约 558 (2002)。

Koshimizu T.: "Heteromultimerization modulates P2X receptor functions through participating extracellular and C-terminal subdomains"J Biol Chem.. 277. 46891-46899 (2002)

小清水 T.：“异源多聚化通过参与细胞外和 C 末端子结构域调节 P2X 受体功能”J Biol Chem.. 277. 46891-46899 (2002)

Shiraishi M: "Inhibitory effects if tramadol on nicotinic acetylcholine receptors in adrenal medullary cells and in Xenopus oocytes expressing α7 receptors"British J. Pharmacology. 136. 207-216 (2002)

Shiraishi M：“曲马多对肾上腺髓质细胞和表达 α7 受体的爪蟾卵母细胞中的烟碱乙酰胆碱受体的抑制作用”British J. Pharmacology 136. 207-216 (2002)。

Yoshimura R.: "Dual phase of functional change in norepinephrine transporter in cultured bovine adrenal medullary cells by long-term treatment with clozapine"Journal of Neurochemistry. 77. 1018-1026 (2001)

Yoshimura R.：“长期用氯氮平治疗培养的牛肾上腺髓质细胞中去甲肾上腺素转运蛋白的双相功能变化”神经化学杂志。