[Rat kidney mitochondrial damage induced by acute cadmium administration].

OBJECTIVE: To evaluate effect of acute cadmium administration on mitochondria from rat kidney. METHODS: 24 male Sprague-Dawley (SD) rats were randomly divided into four groups. Four groups of rats were injected with saline, 0.6, 1.2, and 1.8 mg/kg weight subcutaneously, once daily, for 5 days, respectively. Ultrastructural change of rat kidney mitochondria was observed, and respiration function, membrane potential, mitochondria swelling, and superoxide level were determined. RESULTS: Ultrastructural changes included matrix vacuolation, swelling and condensation of mitochondria. In group of 1.8 mg/kg body weight, the oxygen consumption rate during state 3 respiration [(6.25 +/- 0.61) nmol/L O2 x min(-1) x mg(-1)] and RCR value (2.45 +/- 0.23) were significantly lower than those of control group [(9.66 +/- 1.16) nmol/L O2 x min(-1) x mg(-1)] (P < 0.05), indicating respiration inhibition. The membrane potential and superoxide level of the same group were 85.89% +/- 3.82% and 116.33% +/- 3.06% of control values (P < 0.05), respectively. CONCLUSIONS: Acute cadmium administration can cause rat kidney mitochondrial damage in a dose-effect manner, including inhibition of respiration, dissipation of membrane potential, swelling of mitochondria matrix. Such damage might be related to the increase of mitochondrial free radical.

[Preparation of five ginkgolic acid monomers and their molluscicidal effects against Oncomelania hupensis].

OBJECTIVE: To investigate the molluscicidal activities of the ginkgolic acid(GA) monomers isolated and purified from GAs. METHODS: Five monomers of GAs from the sarcotesta of Ginkgo biloba. were extracted by petrol ether, separated by silica gel column chromatography, purified by semi-prepared reversed-phased HPLC, and identified by LC-MS analysis. The molluscicidal activities of GAs and their monomers against Oncomelania hupensis were determined as referring to the WHO guidelines for laboratory molluscicidal test. RESULTS: The five purified ginkgolic acid monomers were GA(13:0), GA(15:0), GA(15:1), GA(17:1) and GA(17:2), with a side chain of 13, 15, 17 alkyl or ethylenic radicals res pectively on their benzene loop. The five monomer proportions to the total GAs were 17.6%, 3.2%, 52.3%, 23.3% and 3.6% respectively. The order of molluscicidal activities for the five monomers was as follows: GA(13:0)>GA(15:1)>GA(15:0)>GA(17:1)>GA(17:2), and their LC50 for snails was 20.79 mg/L, 22.28 mg/L, 33.76 mg/L, 51.89 mg/L, and 59.10 mg/L respectively after immersion for 24 hours. Two monomers, GA(13:0), and GA(15:1) inhibited the snails' climbing up significantly. CONCLUSION: The molluscicidal activities of GAs may be dependent on the monomer's structure with different number of carbon molecules and double-bonds on the side carbon-chain. The two monomers, GA(13:0) and GA(15:1), are mainly responsible for the molluscicidal activities of GAs and both effectively inhibit snails' climbing up as well. GA(15:0) also shows certain molluscicidal activity.