Donlon M, Hunt W A, Catravas G N, Kaliner M
Life Sci. 1982 Aug 2;31(5):411-6. doi: 10.1016/0024-3205(82)90325-3.
Beta-adrenergic receptors were characterized by measuring the specific binding of 3H-dihydroalprenolol (DHA) on intact isolated rat peritoneal mast cells (RPMC) and on perigranular membranes derived from purified RPMC granules. The specific binding of 3H-DHA reaches an equilibrium within 30 min at 5 degrees C and is linear with cell number. Scatchard analysis reveals two populations of binding sites on intact cells: with KD = 10.6 +/- 2.6 and 129 +/- 4.7 nM and Bmax of 186 +/- 38 and 1200 +/- 415 fmol/10(6) cells, respectively. Each cell contains 120 X 10(3) high-affinity binding sites and 720 X 10(3) low-affinity binding sites. There appears to be neither alpha-adrenergic nor muscarinic cholinergic receptors on the RPMC. Specific binding of 3H-DHA also occurred to isolated granules with perigranular membranes. The binding was saturable with a single population of binding sites with an affinity (KD) of 7.0 +/- 0.45 nM. Maximum binding (Bmax) was calculated at 56.6 +/- 1.9 fmol/10(9) granules. Subfractionation of granule components demonstrated that the specific binding sites appear to be localized exclusively on the perigranular membrane.
通过测量³H - 二氢阿普洛尔（DHA）在完整分离的大鼠腹膜肥大细胞（RPMC）以及从纯化的RPMC颗粒衍生的颗粒周膜上的特异性结合来表征β - 肾上腺素能受体。³H - DHA的特异性结合在5℃下30分钟内达到平衡，并且与细胞数量呈线性关系。Scatchard分析显示完整细胞上有两类结合位点：KD分别为10.6±2.6和129±4.7 nM，Bmax分别为186±38和1200±415 fmol/10⁶个细胞。每个细胞含有120×10³个高亲和力结合位点和720×10³个低亲和力结合位点。RPMC上似乎既没有α - 肾上腺素能受体也没有毒蕈碱胆碱能受体。³H - DHA与带有颗粒周膜的分离颗粒也发生特异性结合。这种结合具有饱和性，有一类结合位点，亲和力（KD）为7.0±0.45 nM。最大结合量（Bmax）计算为56.6±1.9 fmol/10⁹个颗粒。颗粒成分的亚分级显示特异性结合位点似乎仅定位在颗粒周膜上。
