Abstract
The binding of [3H]dopamine to platelet membranes has been examined in an attempt to identify the putative dopamine uptake mechanism of the platelet. [3H]Dopamine has been shown to bind to a 42000 Da glycoprotein in platelet membrane with high affinity (K(d) = 22.6 nM) and binding of [3H]dopamine was competed for by dopamine, molecules with catechol moieties, 5-hydroxytryptamine, GSH and ascorbic acid. Differences in pharmacological profile and molecular mass suggest that [3H]dopamine does not bind to a known receptor, a neuronal-type dopamine transporter or the platelet 5-hydroxytryptamine-uptake site. It is proposed that this novel binding site for dopamine, which has been purified 1000-fold from particulate platelet membrane, is likely to be a component of the dopamine-uptake mechanism of the human platelet.
Original language | English |
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Pages (from-to) | 45-50 |
Number of pages | 6 |
Journal | Biochemical Journal |
Volume | 287 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Jan 1992 |
Externally published | Yes |