[The effect of ginkgo biloba on hypoxic pulmonary hypertension and the role of protein kinase C].
OBJECTIVE
To elucidate whether the mechanism of relieving hypoxic hypertension by ginkgo biloba involves attenuation of the function of protein kinase C(PKC) signal channel.


METHODS
1. Wistar rats were randomly divided into control(C), hypoxic(H) and ginkgo biloba treatment(GB + H) (200 mg.kg-1.d-1, orally) groups (n = 7). Each rat was first measured mean pulmonary arterial pressure (mPAP), mean systemic arterial pressure (mSAP) and the ratio of the weight of right ventricle to that of left ventricle plus septum [RV/(LV + S)], than two main pulmonary artery rings were isolated to exposed to PDBu(a specific activator of PKC) to observe the time-response curve and the dose-response curve in response to 500 nmol/L PDBu and 10-11,000 nmol/L PDBu respectively to evaluate the function of protein kinase C signal channel. 2. Intrapulmonary artery rings of human(IARH) from pneumolobectomy were randomly divided into PDBu, RO318220 (inhibitor of PKC) + PDBu and ginkgolide B(BN52021) + PDBu groups(n = 6), the IARH of three groups were exposed to 1-25 nmol/L PDBu to achieve dose-response curves respectively.


RESULTS
(1) mPAP, RV/(LV + S) of the H group were greater than those of C and GB + H groups respectively (P < 0.05). mPAP of GB + H group was greater than that of C group (P < 0.05). In PA experiments, the function of protein kinase C of H group was higher than those of C and GB + H groups respectively(P < 0.05). (2) In IARH experiments, the function of protein kinase C of PDBu group was higher than those of RO318220 + PDBu and BN52021 + PDBu groups respectively(P < 0.05).


CONCLUSIONS
Ginkgo biloba can reduce chronic hypoxic pulmonary hypertension and relieve the hypertrophy of right ventricle, which is partly related to attenuation of the function of PKC signal channel.
Yang
H
H
Respiratory Department, Tongji Hospital, Tongji Medical University, Wuhan 430030, China.
Xu
Y
Y
Zhang
Z
Z
D000818:Animals; D004224:Diterpenes; D020441:Ginkgo biloba / Q000737:chemistry*; D046934:Ginkgolides; D006976:Hypertension, Pulmonary / Q000188:drug therapy*; D000860:Hypoxia / Q000150:complications*; D007783:Lactones / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008517:Phytotherapy; D011493:Protein Kinase C / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; C045856:ginkgolide B; D011493:Protein Kinase C