The effect of 5-methoxytryptamine on golden hamster gonads is not a consequence of its acetylation into melatonin.
Radioimmunoassay and high performance liquid chromatography were used to determine if the gonadal atrophy induced by late afternoon injections of 5-methoxytryptamine (5-MT) in golden hamsters kept under long photoperiod could be due to the acetylation of this compound into melatonin. An increase in plasma concentrations of melatonin (10-13 nmol/l) was detected 15 min after injection of 130 nmol 5-MT. An injection of 4.3 nmol melatonin generated a similar plasma concentration of melatonin. 5-MT (130 nmol) and melatonin (4.3 nmol) were then injected daily in the late afternoon to golden hamsters kept under long photoperiod. After 8 weeks, 5-MT induced total testicular regression, while melatonin induced partial atrophy only. Thus under these experimental conditions, 5-MT had a physiological activity independent of that of melatonin.
Raynaud
F
F
CNRS URA 1332, Laboratoire de Zoologie, Université Louis Pasteur, Strasbourg, France.
Miguel
J L
JL
Vivien-Roels
B
B
Masson-Pévet
M
M
Pévet
P
P
D008735:5-Methoxytryptamine / Q000494:pharmacology*; D000107:Acetylation; D000818:Animals; D001284:Atrophy / Q000139:chemically induced; D006224:Cricetinae; D008027:Light; D008297:Male; D008550:Melatonin / Q000097:blood / Q000494:pharmacology; D008647:Mesocricetus; D009929:Organ Size; D012701:Serotonin / Q000494:pharmacology*; D013737:Testis / Q000187:drug effects* / Q000473:pathology
D012701:Serotonin; D008735:5-Methoxytryptamine; D008550:Melatonin