Liquid chromatography-electrospray linear ion trap mass spectrometry analysis of targeted neuropeptides in @entity10501 (-/-) XXXX spinal cords reveals significant lower concentration of opioid peptides.

@entity1 @entity9766 @entity19 @entity10501 @entity158 @entity12819 @entity4756
UNASSIGNED: @entity4756 and opioid peptides play a central role in @entity158 transmission, modulation and inhibition. The treatment of @entity158 is very important in medicine and many studies using @entity9766 antagonists failed to show significant analgesic effects in @entity1 . Recent investigations suggest that both pronociceptive tachykinins and the analgesic opioid systems are important for normal @entity158 sensation. The analysis of opioid peptides in @entity10501 (-/-) spinal cord tissues offers a great opportunity to verify the influence of the tachykinin system on specific opioid peptides. The objectives of this study were to develop an HPLC-MS/MRM assay to quantify targeted peptides in spinal cord tissues. Secondly, we wanted to verify if the @entity10501 (-/-) @entity19 endogenous opioid system is hampered and therefore affects significantly the @entity158 modulatory pathways. Targeted neuropeptides were analyzed by high performance liquid chromatography linear ion trap mass spectrometry. Our results reveal that EM-2, Leu-Enk and Dyn A were down-regulated in @entity10501 (-/-) spinal cord tissues. Interestingly, Dyn A was almost 3 fold down-regulated (p<0.0001). No significant concentration differences were observed in @entity19 @entity10501 (-/-) spinal cords for Met-Enk and @entity12819 . The analysis of @entity10501 (-/-) @entity19 spinal cords revealed noteworthy decreases of EM-2, Leu-Enk and Dyn A concentrations which strongly suggest a significant impact on the endogenous @entity158 -relieving mechanisms. These observations may have insightful impact on future analgesic drug developments and therapeutic strategies.
