Effects of opioids on human serotonin transporters

Abstract The serotonin (5-hydroxtryptamine, 5-HT) system plays a role in analgesia and emesis. The aim of this study was to test whether opioids or ketamine inhibit the human 5-HT transporter and whether this increases free plasma 5-HT concentrations. HEK293 cells, stably transfected with the human 5-HT transporter cDNA, were incubated with morphine, hydromorphone, fentanyl, alfentanil, pethidine (meperidine), tramadol, ketamine, and the reference substance citalopram (specific 5-HT transporter inhibitor). The uptake of [3H]5-HT was measured by liquid scintillation counting. In a second series of experiments, study drugs were incubated with plasma of ten healthy blood donors and change of 5-HT plasma-concentrations were measured (ELISA). The end point was the inhibition of the 5-HT transporter by different analgesics either in HEK293 cells or in human platelets ex vivo. Tramadol, pethidine, and ketamine suppressed [3H]5-HT uptake dose-dependently with an $ IC_{50} $ of 1, 20.9, and 230 μM, respectively. These drugs also prevented 5-HT uptake in platelets with an increase in free plasma 5-HT. Free 5-HT concentrations in human plasma were increased by citalopram 1 μM, tramadol 20 μM, pethidine 30 μM, and ketamine 100 μM to 280 [248/312]%, 269 [188/349]%, and 149 [122/174]%, respectively, compared to controls without any co-incubation (means [95 % CI]; all p < 0.005). No change in both experimental settings was observed for the other opioids. Tramadol and pethidine inhibited the 5-HT transporter in HEK293 cells and platelets. This inhibition may contribute to serotonergic effects when these opioids are given in combination, e.g., with monoamine oxidase inhibitors or selective serotonin reuptake inhibitors..

Medienart:

E-Artikel

Erscheinungsjahr:

2014

Erschienen:

2014

Enthalten in:

Zur Gesamtaufnahme - volume:388

Enthalten in:

Naunyn-Schmiedeberg's archives of pharmacology - 388(2014), 1 vom: 22. Okt., Seite 43-49

Sprache:

Englisch

Beteiligte Personen:

Barann, M. [VerfasserIn]
Stamer, U. M. [VerfasserIn]
Lyutenska, M. [VerfasserIn]
Stüber, F. [VerfasserIn]
Bönisch, H. [VerfasserIn]
Urban, B. [VerfasserIn]

Links:

Volltext [lizenzpflichtig]

Themen:

Fentanyl
Ketamine
Meperidine
Morphine
Serotonin (5-hydroxtryptamine)
Tramadol

Anmerkungen:

© Springer-Verlag Berlin Heidelberg 2014

doi:

10.1007/s00210-014-1056-3

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

SPR001960601