| Object: To investigate distribution and immunodensity changes of nitric oxide synthase(NOS), substance P(SP) ,calcitonin gene-related peptide(CGRP) in the superficial dorsal horn , laminae I - II, under two conditions (shame injury, injury), at different times(4,7,14,28d),and to explore the mechanism of chronic neuropathic pain.Methodes: SD rat chronic constriction injury (CCI) hyperalgesia model was used as the chronic neuropathic pain model . NADPH-diaphorase histochemistry to investigate the immunodensities of NOS, histocytochemistry to investigated the immunodensities of SP and CGRP, On the days 4,7,14,28 after CCI operation in experimental control group and chronic neuropathic pain group.Results:1 .Experimental control groups: NOS immunodensities in the dorsal horn ipsilateral to injury little decreased and SP,CGRP immunodensities little increased at day 4. Compared with controlateral to injury in the same group, there is a significant difference (P<0.05) and there is not a significant difference at days 7,14,28 respectively.2.Chronic neuropathic pain groups: NOS immunodensities decreased maximally at day 7 post-injury. Compared with experimental control group, there is a significant difference (P<0.01). This decline persisted at day 28 in the dorsal horn ipsilateral they compared with experimental control group,there is a significant difference (P<0.01). SP,CGRP immunodensities increased maximally at 4 days post-injury. Compared with experimental control group, there is a significant difference (P<0.01).Then they decreased gradually to day 28. But they still higher than experimental control groups, there is a significant difference (P<0.05)Conclusions:The hyperalgesia is concomitant with the increase of SP and CGRP immunodensities in dorsal horn ipsilateral to injury. And the decrease of NOS immunodensities is not concomitant with the hyperalgesia .The hyperalgesia is related with the changes of NOS,SP,CGRP during the chronic neuropathic pain.
|
PDF Full Text Request