摘要
黑皮质素4型受体(melanocortin 4 receptor,MC4R)作为下丘脑参与能量调控过程中的关键性受体,在动物能量代谢调节中被广泛关注。目前,关于该受体在绵羊下丘脑中分布区域的相关报道较少。针对试验过程中MC4R免疫荧光结果不稳定,分布区域不明显的特点,本研究在改进现有MC4R免疫荧光试验方法基础上,对MC4R在绵羊下丘脑的分布区域进行了观察。结果显示,分别经过4%多聚甲醛长时间固定(6 d),Triton X-100(pH≈8.68)长时间通透(2 d),以及3%过氧化氢和0.2 mol/L甘氨酸+0.3%SDS+20%甲醇的预处理后,可以获得稳定且饱满的MC4R免疫荧光结果。MC4R主要分布在绵羊下丘脑的室旁核(arcuate nucleus,ARC)区域,但在弓状核区域并无类似分布。
Melancholic 4 receptor(MC4 R) is a key receptor involved in energy regulation in the hypothalamus and is widely concerned in bodily energy metabolism.At present,the distribution of this receptor in sheep hypothalamus is unclear.Owing to MC4 R immunofluorescences were unstable and there is not sufficient evidence to prove the distribution area.Here,based on the improvement of the MC4 R immunofluorescence assay,we identified the distribution of MC4 R in the hypothalamus of sheep,through using,long-time external fixation(6 days),TritonX-100(pH≈8.68) for 4 days,and progressing the pretreatment with 3% hydrogen peroxide and 0.2 mol/L glycine + 0.3% SDS + 20% methanol.MC4 R immunofluorescence results can be stably obtained,and is mainly distributed in the paraventricular nucleus of hypothalamus(PVH) of sheep and does not show a concentrated distribution in the arcuate nucleus(ARC) neucleus.
引文
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