Abstract:

Objective 　To discuss the effects of tyrosine hydroxylase (TH) in the occurrence and development of high altitude hypertension by observing the changes of the ultramicrostructure of the sympathetic nerve cells and the expression TH in superior cervical ganglion of rats.　Methods　WKY rats were randomly divided to be raised at plain or in the altitude chambers imitating the environment at 5000 m for 1 d, 3 d and 7 d, respectively. Electron microscopy was used to examine the changes of the ultramicrostructure of the sympathetic nerve cells. Real-time PCR and Western blot method were used to examine the mRNA and protein expression of TH.　Results　The blood pressure of hypoxia rats was obviously higher than C group（P<0.05）;the results of Real-time PCR and Western blot showed that mRNA and protein expression of TH in superior cervical ganglion of H1 and H3 groups were lower than C group（P<0.05）, but the expression in H7 group were higher than C group. The results of electron microscopy showed that the morphology of sympathetic nerve cells, quantity and structure of cell organelle were changed in the circumstance of plateau.　Conclusions   TH may participate in the occurrence of high altitude hypertension through certain complex mechanisms.

Key words: Plateau, Hypoxia, Sympathetic ganglion, TH