Differential effects of some transition metal cations on the binding of β-carboline-3-carboxylate and diazepam
The interaction of benzodiazepines and β-carbolines with metal cations was investigated. Among numerous transition metal cations, only three, Co2+, Ni2+ and Zn2+, specifically inhibited the binding of [3H]β-carboline-3-carboxylate ethyl ester (β-CCE). The effects of these cations on [3H]β-CCE binding were exactly opposite to those on [3H]diazepam binding. The effects of these cations was not dependent on lipid peroxidation. The differential effect of these cations may reflect a general difference in the way agonists and antagonists bind to the benzodiazepine receptor.
KeywordsLipid Ester Ethyl Lipid Peroxidation Diazepam
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