ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: Kinetic studies showed that under appropriate conditions, [3H]clonidine binds to two distinct receptor sites in calf cortex membranes. At 23°C, binding was obtained at a low-affinity site (dissociation constant, KD= 5.4 nm) and a high-affinity site (KD= 1.1 nm). In contrast, at 0°C, selective binding occurred to the low-affinity site only. Consequently, at 0°C, it was possible to evaluate the interaction of drugs with the low-affinity receptor directly. On the other hand, competition with the high-affinity receptor could be ascertained by generating displacement curves representing the differential between specific binding values obtained at 23 and 0°C. Guanine nucleotides selectively decreased binding to the high-affinity site without apparent influence on the low-affinity [3H]clonidine binding. The activities of various pharmacological agents at the low- and high-affinity clonidine receptors are discussed and compared with WB-4101 binding data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1981.tb05292.x
