Related Experiment Videos
Nociceptin (1 - 7) antagonizes nociceptin-induced hyperalgesia in mice
T Sakurada1, S Sakurada, S Katsuyama
1Department of Biochemistry, Daiichi College of Pharmaceutical Sciences, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511, Japan.
British Journal of Pharmacology
|November 11, 1999
Summary
Nociceptin administration caused hyperalgesia in mice. However, its N-terminal fragment, nociceptin (1-7), reduced this effect, suggesting endogenous fragments modulate nociceptin
Area of Science:
- Neuroscience
- Pharmacology
- Pain Research
Background:
- Nociceptin is a key peptide in pain modulation.
- The role of nociceptin's N-terminal fragments in spinal cord pain signaling is not fully understood.
Purpose of the Study:
- To investigate the effects of nociceptin and its N-terminal fragment, nociceptin (1-7), on nociception in mice.
- To determine if nociceptin (1-7) modulates nociceptin-induced hyperalgesia.
Main Methods:
- Intrathecal administration of nociceptin and nociceptin (1-7) into conscious mice.
- Measurement of nociceptive thermal threshold using tail-flick and paw-withdrawal tests.
- Co-administration of nociceptin and nociceptin (1-7) to assess modulatory effects.
Main Results:
- Nociceptin (3.0 fmol) significantly reduced the nociceptive thermal threshold, inducing hyperalgesia.
- Nociceptin (1-7) alone had no significant effect on nociception.
- Co-administration of nociceptin (1-7) significantly reduced nociceptin-induced hyperalgesia.
- High-dose nociceptin-induced analgesia was not antagonized by nociceptin (1-7).
Conclusions:
- Endogenously formed N-terminal fragments of nociceptin may play a role in modulating nociceptin's hyperalgesic actions within the spinal cord.
- This suggests a complex regulatory mechanism for nociceptin signaling in pain pathways.