Effects of intrathecal administration of dexmedetomidine on morphine tolerance and inflammatory response in rats / 重庆医学
Chongqing Medicine
; (36): 4771-4773, 2017.
Article
в Zh
| WPRIM
| ID: wpr-664407
Ответственная библиотека:
WPRO
ABSTRACT
Objective To investigate the effects of intrathecal dexmedetomidine administration on the development of morphine tolerance and spinal inflammatory responses.Methods Thirty-three male SD rats weighing 180~200 g were randomly divided into 3 groups (n=11)Saline group (group NS),Morphine group (group M) and Dexmedetomidine group (group Dex).Animals of group NS were intrathecally injected with 10 tμL of saline daily for seven days;Animals in group M were intrathecally injected with 15 μg of morphine daily for seven days;Animals in group Dex were intrathecally injected with a mixture of 15μg morphine and 1.5 μg dexmedetomidine daily for seven days.At 1,3,5 and 7 day of intrathecal injection,hot water tail-flick test were used to evaluate analgesic response to thermal stimuli.After the last episode of behavioral test,Western blot analysis was applied to determine the protein levels of Iba-1 (microglial marker),IL-1β,TNF-a and phospho-p38MAPK (p-p38) in the spinal cord.In addition,microglia in the spinal cord was immuno-stained with anti-Iba-1 antibody and the densities of microglia were calculated.Results In group M and Dex,the values of maximal possible effect (MPE) in tail-flick test decreased gradually along with repeated morphine administration (P<0.05).Compared with group NS,the values of MPE in tail-flick test at 1,3,5 and 7 day of morphine tolerance were higher in group M (P<0.05).Compared with group M,the values of MPE in tail-flick test at 3,5 and 7 day of morphine tolerance were higher in group Dex (P<0.05).Compared with group NS,the spinal protein levels of Iba-1,IL-1L TNF-α and p-p38 as well as the density of Iba-1 positive cells in group M were increased (P<0.05).However,Compared with group M,the of Iba-1,IL-1β,TNF-α and p-p38 as well as the density of Iba-1 positive cells were decreased(P<0.05).Conclusion Intrathecal dexmedetomidine administration can attenuate morphine tolerance by inhibiting microglia-mediated inflammatory responses in the spinal cord.
Полный текст:
1
База данных:
WPRIM
Язык:
Zh
Журнал:
Chongqing Medicine
Год:
2017
Тип:
Article