Mitogenic effect of serotonin in human small cell lung carcinoma cells via both 5-HT1A and 5-HT1D receptors.
We have recently shown that the mitogenic effect of serotonin (5-hydroxytryptamine, 5-HT) on human small lung carcinoma (SCLC) cells is at least partly due to stimulation of a 5-HT1D receptor type. We now report that the 5-HT1A receptor agonist R(+)-8-hydroxy-2-(di-n- propylamino)tetralin (8-OH-DPAT) is also capable of stimulating [3H]thymidine incorporation into SCLC GLC-8 cells, although with lower efficacy than 5-HT. The simultaneous administration of maximal doses of 8-OH-DPAT and the 5-HT1D receptor agonist sumatriptan reproduced the maximal [3H]thymidine incorporation observed with 5-HT alone. The 5-HT1A receptor antagonists spiperone and SDZ 216-525 completely abolished the effect of 8-OH-DPAT (IC50 30 nM for both drugs) behaving as pure antagonists. Accordingly, the two drugs partially inhibited the mitogenic effect of 5-HT. These data indicate that the mitogenic effect of 5-HT in SCLC cells involves both 5-HT1A and 5-HT1D receptor types.
Cattaneo
M G
MG
Department of Medical Pharmacology, University of Milan, Italy.
Fesce
R
R
Vicentini
L M
LM
D018288:Carcinoma, Small Cell / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism*; D008934:Mitogens; D011985:Receptors, Serotonin / Q000187:drug effects*; D012701:Serotonin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D008934:Mitogens; D011985:Receptors, Serotonin; D012701:Serotonin