Differential effects of the novel antidepressant tianeptine on L-5-hydroxytryptophan (5-HTP)-elicited corticosterone release and body weight loss.
Biochemical and behavioural experiments have indicated that the novel antidepressant tianeptine stimulates 5-hydroxytryptamine (5-HT) reuptake. The present study has explored the influence of acute tianeptine pretreatment upon corticosterone release and body weight loss following L-5-hydroxytryptophan (5-HTP) administration in conscious rats. Administration of 5-HTP (20 mg/kg i.v.) increased plasma corticosterone levels to a similar extent in rats pretreated either with saline or tianeptine (10 mg/kg i.p., 60 min beforehand). Besides, prior administration of benserazide (50 mg/kg i.p., 30 min beforehand), an inhibitor of peripheral aromatic L-amino acid decarboxylase, prevented 5-HTP-induced corticosterone release in both saline- and tianeptine-pretreated rats. However, combined administration of benserazide and 5-HTP decreased overnight body weight in saline-, but not in tianeptine-pretreated rats. These results suggest that tianeptine preferentially activates 5-HT reuptake in central serotonergic neurones.
Broqua
P
P
Laboratoire de Pharmacologie, Groupe de Neuropharmacologie, CNRS, CHU Necker-EM, Paris, France.
Baudrie
V
V
Chaouloff
F
F
D006916:5-Hydroxytryptophan / Q000494:pharmacology*; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D001545:Benserazide / Q000494:pharmacology; D001835:Body Weight / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013841:Thiazepines / Q000494:pharmacology*
D000928:Antidepressive Agents; D013841:Thiazepines; C050504:tianeptine; D001545:Benserazide; D006916:5-Hydroxytryptophan; D003345:Corticosterone