Neuroendocrine effects of citalopram, a selective serotonin re-uptake inhibitor, during lifespan in humans.
OBJECTIVE
Serotonergic system contributes to the regulation of hypothalamus-pituitary-adrenal axis. In humans, serotonergic agonists increase PRL, ACTH, and cortisol, while serotonin (5HT) influence on GH is controversial. Central 5HT activity and neuroendocrine function change during lifespan.


METHODS
To clarify the neuroendocrine response to 5HT across lifespan, we assessed ACTH, cortisol, DHEA, PRL, and GH responses to citalopram (CT) in young adults (YA) (no.=12, 29.2±1.7 yr mean±SEM), middle aged (MA) (no.=12, 54.3±0.9 yr), and elderly (ES) (no.=12, 69.3±0.9 yr) males. All the subjects received placebo (saline iv over 120 min) or CT (20 mg iv over 120 min). Blood samples were taken every 15 min up to 240 min.


RESULTS
During placebo, ACTH, cortisol, GH, and PRL were similar in all groups while DHEA showed an age-dependent reduction from middle age (p<0.001). During CT, ACTH, and cortisol were higher than during placebo in YA (p<0.05) and even more in MA (p<0.01 vs placebo, p<0.05 vs YA); in ES, the increase of both ACTH and cortisol (p<0.05 vs placebo) was lower than in MA (p<0.05) and higher than in YA (p<0.05 for cortisol only). No changes were observed for DHEA, GH, and PRL in any group.


CONCLUSIONS
Corticotrope response to CT is age-dependent in normal men, being amplified starting from middle age, suggesting precocious changes in the serotonergic neuroendocrine control during lifespan. CT is a useful tool to evaluate the age-dependent serotonergic function in humans.
Berardelli
R
R
Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Turin, Corso Dogliotti 14, Turin, Italy.
Margarito
E
E
Ghiggia
F
F
Picu
A
A
Balbo
M
M
Bonelli
L
L
Giordano
R
R
Karamouzis
I
I
Bo
M
M
Ghigo
E
E
Arvat
E
E
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D000368:Aged; D000375:Aging / Q000097:blood / Q000187:drug effects / Q000502:physiology*; D015283:Citalopram / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D003687:Dehydroepiandrosterone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009490:Neurosecretory Systems / Q000187:drug effects* / Q000502:physiology; D010919:Placebos; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology; D013997:Time Factors
D000324:Adrenocorticotropic Hormone; D015283:Citalopram; D003687:Dehydroepiandrosterone; D006854:Hydrocortisone; D010919:Placebos; D017367:Selective Serotonin Reuptake Inhibitors