Inhibition of MAO activity, 3H-imipramine binding, 3H-paroxetine binding and 3H-5-HT uptake by human cerebrospinal fluid
Addition of small amount of human cerebrospinal fluid (CSF) inhibited both types of MAO in monkey brain mitochondria. The specific binding of 3H-paroxetine decreased remarkably with increasing CSF volumes, while 3H-imipramine binding was slightly inhibited. Scatchard analysis of 3H-paroxetine binding in the presence and absence of CSF indicated that the inhibitory effect was associated with a decreased Bmax without an appreciable change in Kd. Addition of CSF induced an inhibition of uncompetitive 3H-5-HT uptake to monkey cerebral membranes. These results indicate that the materials in human CSF inhibit 3H-paroxetine binding, and modulate the uptake system for 5-HT.
KeywordsScatchard Analysis Serotonin Uptake Monkey Brain Paroxetine Binding Imipramine Binding
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