[Anti-nociceptive effect of calcitonin on chronic pain associated with osteoporosis].
Calcitonin is widely used clinically for alleviating hyperalgesia as well as recovering bone mass associated with osteoporosis. However, it's analgesic mechanism is not clear, although involvement of serotonergic system is suggested. We investigated a mechanism of calcitonin actions using ovariectomized rats which exhibit hyperalgesia. Whole-cell patch-clamp recording was employed to test an effect of calcitonin on synaptic transmission in the dorsal horn. In normal rats, transmitter release from fine myelinated Adelta and unmyelinated C afferents was depressed by serotonin, while the effect of 5-HT on C afferents was disappeared in OVX rats. This elimination of the 5-HT action was reversed by administration of calcitonin.
Yoshimura
M
M
Department of Integrative Physiology, Graduate School of Medical Science Kyushu University.
Furue
H
H
Ito
A
A