Ovariectomy-induced hyperalgesia and antinociceptive effect of elcatonin, a synthetic eel calcitonin.
Using ovariectomized (OVX) rats in the tail-withdrawal nociceptive test, we examined OVX-induced hyperalgesia and the antinociceptive effect of subcutaneously administered elcatonin, a synthetic derivative of eel calcitonin ([Asu1.7] eel calcitonin). Because tail-withdrawal latency was significantly and continuously reduced and bone mineral density decreased in OVX rats compared with those of sham-operated rats, it was demonstrated that ovariectomy induced prolonged hyperalgesia and osteoporosis. After repeated administrations for 3 or 4 weeks, subcutaneously injected elcatonin increased the latency of the OVX rats in a dose-dependent manner, compared to the vehicle-treated OVX rats. At a dose of 20 U/kg/day, there were significant differences (p < 0.01) in the latency between the elcatonin- and vehicle-treated OVX rats. This effect of elcatonin was completely inhibited by p-chlorophenylalanine treatment, suggesting that the central serotonergic system may be involved in the elcatonin antinociception of OVX-induced hyperalgesia.
Shibata
K
K
Laboratory for Pharmacology, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd., Ohito, Shizuoka, Japan.
Takeda
M
M
Ito
A
A
Takeda
M
M
Sagai
H
H
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism; D015519:Bone Density / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D002116:Calcitonin / Q000031:analogs & derivatives* / Q000494:pharmacology; D004524:Eels; D005260:Female; D006930:Hyperalgesia / Q000209:etiology* / Q000503:physiopathology; D010052:Ovariectomy; D010147:Pain Measurement / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism; D013116:Spinal Cord / Q000187:drug effects / Q000378:metabolism
D000700:Analgesics; D015306:Biogenic Monoamines; D012701:Serotonin; D002116:Calcitonin; C012755:elcatonin