Since there exist conflicting results with regard to the possible effect of aging on platelet [H-3]-imipramine binding, taken as a peripheral marker of the serotonin (5-HT) transporter, we reinvestigated this matter by comparing the binding of the more selective ligand [H-3]-paroxetine in 20 aged and 23 young subjects. The results showed that neither the maximum binding capacity nor the dissociation constant (K-d) were significantly different in the two groups. When the subjects were compared according to sex, the young females revealed a statistically significant lower K-d than the males, while the contrary was true for the aged females. The K-d was significantly and negatively correlated to age in males. In addition, a significant age x gender interaction was also observed. Therefore, the sex of a subject would seem to provoke significant age-related changes in the K-d of [H-3]-paroxetine binding to platelet membranes. This might indicate modifications in the 5-HT transporter that could form the basis of a sex-related difference in vulnerability to disorders, such as depression, where a dysfunction at this level is hypothesized. (C) 1998 Elsevier Science B.V.
Effect of aging and sex on the [H-3]-paroxetine binding to human platelets
ROSSI, ALESSANDRA;PALEGO, LIONELLA;GIANNACCINI, GINO;LUCACCHINI, ANTONIO;
1998-01-01
Abstract
Since there exist conflicting results with regard to the possible effect of aging on platelet [H-3]-imipramine binding, taken as a peripheral marker of the serotonin (5-HT) transporter, we reinvestigated this matter by comparing the binding of the more selective ligand [H-3]-paroxetine in 20 aged and 23 young subjects. The results showed that neither the maximum binding capacity nor the dissociation constant (K-d) were significantly different in the two groups. When the subjects were compared according to sex, the young females revealed a statistically significant lower K-d than the males, while the contrary was true for the aged females. The K-d was significantly and negatively correlated to age in males. In addition, a significant age x gender interaction was also observed. Therefore, the sex of a subject would seem to provoke significant age-related changes in the K-d of [H-3]-paroxetine binding to platelet membranes. This might indicate modifications in the 5-HT transporter that could form the basis of a sex-related difference in vulnerability to disorders, such as depression, where a dysfunction at this level is hypothesized. (C) 1998 Elsevier Science B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
