神经递质组胺主要在星形胶质细胞中失活吗？

Is neurotransmitter histamine predominantly inactivated in astrocytes?

作者信息

Rafałowska U, Waśkiewicz J, Albrecht J

机构信息

Department of Neurochemistry, Polish Academy of Sciences, Warsaw, Poland.

出版信息

Neurosci Lett. 1987 Sep 11;80(1):106-10. doi: 10.1016/0304-3940(87)90504-0.

DOI:10.1016/0304-3940(87)90504-0

PMID:2889175

Abstract

Rat synaptosomes and astroglia cell-enriched fraction were tested for the uptake of histamine (HA) and its precursor histidine, and the activities of the HA-synthesizing enzyme, histidine decarboxylase (HD) and HA-metabolizing enzyme, histamine methyltransferase (HMT). While histidine uptake was more active into synaptosomes than into astrocytes, only astrocytes were capable of a significant HA uptake. Kinetic analysis of the astrocytic HA uptake revealed a high affinity-low capacity system (Km = 5 X 10(-7) M, Vmax = 1.6 X 10(-12) mol.min-1 X mg-1) similar to the astroglial transport systems for other neurotransmitters. HMT was 70% more active in astrocytes than in synaptosomes, whereas HD activity was not different in these two preparations. The results indicate that astrocytes could be the major site of neurotransmitter HA inactivation.

摘要

对大鼠突触体和富含星形胶质细胞的组分进行了组胺（HA）及其前体组氨酸摄取的测试，以及HA合成酶组氨酸脱羧酶（HD）和HA代谢酶组胺甲基转移酶（HMT）的活性测试。虽然组氨酸进入突触体的摄取比进入星形胶质细胞更活跃，但只有星形胶质细胞能够大量摄取HA。对星形胶质细胞HA摄取的动力学分析显示，其为高亲和力 - 低容量系统（Km = 5×10（-7）M，Vmax = 1.6×10（-12）mol·min-1·mg-1），类似于其他神经递质的星形胶质细胞转运系统。HMT在星形胶质细胞中的活性比在突触体中高70%，而HD活性在这两种制剂中没有差异。结果表明，星形胶质细胞可能是神经递质HA失活的主要部位。