Taylor D P, Pert C B
Proc Natl Acad Sci U S A. 1979 Feb;76(2):660-4. doi: 10.1073/pnas.76.2.660.
The binding of radiolabeled vasoactive intestinal polypeptide (VIP) to rat brain membranes was investigated. Specific binding of 125I-labeled VIP was reversible and saturable (Bmax = 2.2 pmol/g of wet tissue). Brain membranes exhibited a high affinity for 125I-labeled VIP (KD = 1 nM) at a single class of noninteracting sites. Binding of 125I-labeled VIP paralleled its immunohistochemical localization, being enriched in cerebral cortex, hippocampus, striatum, and thalamus, with the notable exception of the hypothalamus, which had low levels of binding. The density of sites was greater in synaptosomal fractions relative to mitochondrial or nuclear fractions. Secretin and partial sequences of it and VIP inhibited binding to brain membranes with an order of potency similar to that found in other systems. The findings suggest the existence of a unique new class of brain receptors.
研究了放射性标记的血管活性肠肽(VIP)与大鼠脑膜的结合情况。125I标记的VIP的特异性结合是可逆的且具有饱和性(Bmax = 2.2 pmol/克湿组织)。脑膜在单一类非相互作用位点对125I标记的VIP表现出高亲和力(KD = 1 nM)。125I标记的VIP的结合与其免疫组织化学定位平行,在大脑皮层、海马体、纹状体和丘脑富集,下丘脑是显著例外,其结合水平较低。相对于线粒体或核部分,突触体部分的位点密度更大。促胰液素及其部分序列以及VIP以与其他系统中发现的效力顺序相似的方式抑制与脑膜的结合。这些发现提示存在一类独特的新型脑受体。