Ricci A, Rossodivita A, Amenta F
Dipartimento di Scienze Cardiovascolari e Respiratorie, Università La Sapienza, Roma, Italy.
Naunyn Schmiedebergs Arch Pharmacol. 1991 Aug;344(2):259-61. doi: 10.1007/BF00167228.
The binding of the DA-2 receptor antagonist [3H]-spiroperidol, in the presence of appropriate concentrations of ketanserin to avoid the possible labelling of 5-HT-2 sites, was studied in sections of rat kidney using combined radioreceptor assay and light microscope autoradiography. [3H]-Spiroperidol was bound by sections of rat kidney in a manner consistent with the labelling of a single class of high affinity of DA-2 sites. Scatchard analysis of the binding isotherms showed a Kd value of 2.5 +/- 0.2 nmol/l and a Bmax value of 129.5 +/- 6.8 fmol/mg protein. Light microscope autoradiography, centered on the renal cortex, revealed the development of silver grains within cortical convoluted tubules. Silver grains were rather homogeneously distributed to both proximal and distal convoluted tubules, with no specific glomerular localization. These findings do not support the assumption of the existence of glomerular DA-2 receptors in the rat kidney.
在适当浓度的酮色林存在下，为避免5-HT-2位点可能的标记，使用联合放射受体测定法和光学显微镜放射自显影术，研究了DA-2受体拮抗剂[3H]-螺哌啶醇在大鼠肾脏切片中的结合情况。[3H]-螺哌啶醇与大鼠肾脏切片的结合方式与单一类高亲和力DA-2位点的标记一致。结合等温线的Scatchard分析显示，Kd值为2.5±0.2 nmol/l，Bmax值为129.5±6.8 fmol/mg蛋白质。以肾皮质为中心的光学显微镜放射自显影显示，皮质曲管内有银粒形成。银粒在近端和远端曲管中分布相当均匀，在肾小球中没有特定定位。这些发现不支持大鼠肾脏中存在肾小球DA-2受体的假设。
