Smoking was associated with increased platelet 5HT2A receptor density compared to nonsmokers (82.7 vs 40.0 fmol/mg protein; P<0.005) and increased GPIIb/IIIa receptor binding.
Observational (n=52)
Is smoking associated with increased platelet serotonin receptor density and platelet activation?
Smoking is associated with increased platelet serotonin receptor density and GPIIb/IIIa receptor binding, suggesting that serotonergic dysfunction may contribute to the development of cardiovascular disease in smokers.
Absolute Event Rate: 82.7% vs 40%
p-value: p=<0.005
This study sought to determine whether depressive symptoms and/or platelet serotonin receptor (5HT2A) density are associated with increased platelet activation (PA) found among smokers. Flow cytometric detection of PA was used to study 36 smokers and 16 nonsmokers, aged 18 to 48 years. Subjects were tested at baseline and after either smoking 2 cigarettes (smokers) or a similar resting interval (nonsmokers). Assessment of PA included both platelet secretion and fibrinogen receptor (GPIIb/IIIa) binding. Platelet 5HT2A receptor binding and saturation were tested using 3HLSD, and depressive symptoms were measured using the Beck Depression Inventory. Platelet 5HT2A receptor density was increased among smokers versus nonsmokers (82.7+/-67.7 versus 40.0+/-20.2 fmol/mg protein; P<0.005), and there was a dose-dependent relationship between receptor density and packs/d among smokers. Baseline wound-induced GPIIb/IIIa binding at 1 minute and GPIIb/IIIa binding in response to collagen stimulation in vitro was increased among smokers (P<0.05); there were no changes in PA among smokers after smoking, and platelet secretion was not elevated among smokers. Depressive symptoms were associated with 5HT2A receptor density among nonsmokers (P<0.005), but no such relationship was evident among smokers; PA was unrelated to 5HT2A receptor density in either group. The findings indicate that smoking is associated with increased platelet serotonin receptor density and with increased GPIIb/IIIa receptor binding, although these 2 factors are not related to each other or to depressive symptoms among smokers. Serotonergic dysfunction may be an important factor in the development of cardiovascular disease among smokers.
Markovitz et al. (Mon,) conducted a observational in Smoking (n=52). Smoking vs. Nonsmokers was evaluated on Platelet 5HT2A receptor density (p=<0.005). Smoking was associated with increased platelet 5HT2A receptor density compared to nonsmokers (82.7 vs 40.0 fmol/mg protein; P<0.005) and increased GPIIb/IIIa receptor binding.