Correlation between platelet alpha(2)-adrenoreceptors and symptom severity in major depression.
BACKGROUND
Abnormalities in different parameters of the norepinephrine system have been widely described in major depression. The presence of alpha(2)-adrenoreceptors in blood platelets, similar to those in the brain, prompted us to evaluate them in depressed patients, as compared with healthy controls.


METHODS
Fifteen outpatients affected by major depression, according to DSM IV criteria, and 15 comparable healthy control subjects, were included in the study. The alpha(2)-adrenoreceptors were measured by means of the specific binding of [(3)H]rauwolscine, a highly selective antagonist for this receptor subtype. The severity of depression was assessed by means of the Hamilton Rating Scale for Depression (HRSD).


RESULTS
The results did not show any difference in [(3)H]rauwolscine binding parameters (B(max) and K(d)) between patients and controls. However, in the patients, a significant and positive correlation between B(max), which measures the density of the receptors, and HRSD total score was detected.


CONCLUSIONS
Therefore, although no change in alpha(2)-adrenoreceptors seems to occur in major depression, the density of these receptors would seem to be related to the severity of depressive symptoms.
Marazziti
D
D
Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, University of Pisa, Italy. dmarazzi@psico.med.unipi.it
Baroni
S
S
Masala
I
I
Di Nasso
E
E
Giannaccini
G
G
Betti
L
L
Lucacchini
A
A
Cassano
G B
GB
D000328:Adult; D001792:Blood Platelets / Q000378:metabolism*; D003866:Depressive Disorder / Q000097:blood*; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D011869:Radioligand Assay; D018341:Receptors, Adrenergic, alpha-2 / Q000097:blood*; D015016:Yohimbine / Q000378:metabolism*
D018341:Receptors, Adrenergic, alpha-2; D015016:Yohimbine