Significant correlation between 14C-5-HT uptake by and 3H-paroxetine binding to platelets from healthy volunteers.
The lack of correlation between 5-HT uptake by platelets and the ability of platelet membrane to bind antidepressant drugs, particularly imipramine, has been reported. However, more recently it has been suggested that 3H-paroxetine could be a better drug with which to study the platelet 5-HT uptake mechanism in disease states. We have therefore compared the ability of platelet-rich plasma (PRP) from normal individuals to take up 5-HT with the ability of platelet membranes to bind paroxetine. A significant correlation was apparent between the Vmax of 14C-5-HT uptake by PRP and the Bmax of 3H-paroxetine binding to platelet membrane from 30 individuals (r = 0.6468, p = 0.0001). Furthermore, this correlation was highly significant in the 20 female (r = 0.7768, p = 0.00006) but not in the 10 male volunteers. There was also a significant association between Vmax and Bmax and the month of blood sampling but this did not totally account for the correlation between Vmax and Bmax. The simultaneous measurement of 5-HT uptake by PRP and paroxetine binding to platelet membranes from both depressed patients and matched controls should be carried out to confirm and extend these findings.
Maguire
K
K
Department of Psychiatry, University of Melbourne, Victoria, Australia.
Tuckwell
V
V
Pereira
A
A
Dean
B
B
Singh
B
B
D000328:Adult; D001792:Blood Platelets / Q000378:metabolism*; D002250:Carbon Radioisotopes; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D017374:Paroxetine / Q000097:blood*; D011869:Radioligand Assay; D012016:Reference Values; D012701:Serotonin / Q000097:blood*; D014316:Tritium
D002250:Carbon Radioisotopes; D014316:Tritium; D012701:Serotonin; D017374:Paroxetine