摘要
Behaviouzal studies suggested that cerebral angiotensin Ⅱ (AⅡ) plays an important role in the development of tolerance to electroacupuncture (EA) analgesia. Observations made in this study revealed an increase in AⅡ immunoreactivity (AⅡ-it) in both CSF and brain as well as an increase in the cerebral content of AⅠ-ir in rats rendered tolerant to EA. The extracts of brain from rats receiving EA for 1h and 3h were subjected to gel filtration and the elution profile was compared with that of normal brain extract. There was a marked right shift of the AⅡ peak from the large molecule precursor to the small molecule AⅡ-ir.The latter peak showed the same retention time in HPLC system as that of AⅡ. The results suggest that the acceleration of the synthesis and release of AⅡ during s Iong-term EA stimulation might constitute one of the mechanisms for EA tolerance.
Behaviouzal studies suggested that cerebral angiotensin Ⅱ (AⅡ) plays an important role in the development of tolerance to electroacupuncture (EA) analgesia. Observations made in this study revealed an increase in AⅡ immunoreactivity (AⅡ-it) in both CSF and brain as well as an increase in the cerebral content of AⅠ-ir in rats rendered tolerant to EA. The extracts of brain from rats receiving EA for 1h and 3h were subjected to gel filtration and the elution profile was compared with that of normal brain extract. There was a marked right shift of the AⅡ peak from the large molecule precursor to the small molecule AⅡ-ir.The latter peak showed the same retention time in HPLC system as that of AⅡ. The results suggest that the acceleration of the synthesis and release of AⅡ during s Iong-term EA stimulation might constitute one of the mechanisms for EA tolerance.
基金
Proiect supported by the National Natural Science Foundation of China, and a grant from NIDA, USA (DA 03983).