Heterogeneity between rat and calf peripheral-type benzodiazepine binding sites: differential sensitivity to Triton X-100.
The effect of various detergents treatment on the specific binding of [3H]PK 11195 (2nM) to peripheral-type benzodiazepine binding sites (PBS) in calf and rat kidney, adrenal gland, and cerebral cortex membranes was studied. At a concentration of 0.025%, Triton X-100 increased [3H]PK 11195 specific binding to calf kidney, adrenal gland, and cerebral cortex membranes by 20-40%. At the same concentration, Triton X-100 scarcely affected specific binding of [3H]PK 11195 to rat cerebral cortex but decreased binding to rat kidney and adrenal gland membranes by 20-30%. At a concentration of 0.05% of Triton X-100, [3H]PK 11195 specific binding to calf kidney, adrenal gland, and cerebral cortex membranes was increased by 10-20%; whereas [3H]PK 11195 specific binding to rat kidney, adrenal gland, and cerebral cortex membranes was decreased by more than 40%. The increase in [3H]PK 11195 specific binding to calf kidney membranes following Triton X-100 (0.05%) treatment was apparently due to an increase in the binding affinity of PBS, since the density remained unaltered; whereas, the decrease in [3H]PK 11195 specific binding to rat kidney membranes was due to a decrease in both binding affinity and density of PBS. On the other hand, the detergents 3- [(3- cholamidopropyl)- dimethylammonio] - 1 - propane sulfonate (CHAPS), Tween 20, deoxycholic acid, and digitonin have a similar effect on [3H]PK 11195 specific binding to PBS in both calf and rat kidney membranes.
Awad
M
M
Rappaport Family Institute for Research in the Medical Sciences, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa.
Gavish
M
M
D000311:Adrenal Glands / Q000187:drug effects; D000818:Animals; D002417:Cattle; D002540:Cerebral Cortex / Q000187:drug effects; D003902:Detergents; D007546:Isoquinolines / Q000378:metabolism; D007668:Kidney / Q000187:drug effects; D008297:Male; D017830:Octoxynol; D009928:Organ Specificity; D011092:Polyethylene Glycols; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000187:drug effects*; D013045:Species Specificity; D013501:Surface-Active Agents
D003902:Detergents; D007546:Isoquinolines; D011963:Receptors, GABA-A; D013501:Surface-Active Agents; D011092:Polyethylene Glycols; D017830:Octoxynol; C037850:PK 11195