The present study was to investigate whether metallothionein(MT)was involved in sensitivity of testis to cadmium (Cd) and protection of rats from Cd-induced testis damages.The rats were treated by intraperitoneal injection with 0.2,0.4,and 0.8mgCd/kg BW for 7days.The atomic absorption spectrophotometry and cadmium hemoglobin affinity assay were applied to evaluate the contents of Cd and MT in testis and liver.The testis glutathione(GSH),malondialdehyde(MDA)and daily sperm production were measured.There were substantial increases of both Cd and MT in the liver after Cd exposure.The testis Cd and MT contents were lower than those in the corresponding liver in Cd-exposed rats.Low doses of Cd (0.2and0.4 mg/kgBW) induced MT in testis,while a significant decline of MT was found in rats treated with 0.8mgCd/kgBW. By a concomitant decrease of MT,there was an obvious increase of MDA and marked decreases of GSH,daily sperm production in rats treated with 0.8mgCd/kgBW.These findings suggested MT was more difficult to be induced in the testis than in the liver by Cd,which might account for the high susceptibility of testis to Cd.MT, increased by a low dose of Cd,played an important role in protecting testis against Cd toxicity by sequestering and antioxidating.

Carbaryl, one of the most important insecticides,is widely produced and used. To explore carbaryl-induced genotoxic effects of spermatozoa, particularly DNA damage and chromosome aberrations(CA),we firstly examined conventional semen parameters, the progression and motion parameters of the spermatozoa among 16 carbaryl-exposed workers and 30 internal and external control individuals.Sperm DNA damage represented as positive percentage of DNA fragmentation was detected by a modified terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay.Then numerical CA of chromosome X,Y and 18 were investigated by multicolor fluorescence in situ hybridization (FISH). The results showed significant differences in the percentage of sperm abnormality between carbaryl-exposed group and the external control group (P=0.008). Mean (

Aims: To determine sperm nuclear DNA integrity and to investigate the relation between fenvalerate(FE)exposure and spermatozoa DNA damage. Methods: Sperm DNA fragmentation was detected by a modified alkaline single cell gel electrophoresis (Comet) assay and a terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL) assay. The olive tail moment (OTM) and percentage tail DNA were measured by the Comet assay, and cell positive percentage was measured by the TUNEL assay for DNA damage evaluation. Results: he DNA integrity of spermatozoa of external and internal control groups were both significantly greater than that of the FE exposed group. The median value of tail DNA percentage in the exposure group was 11.30, which was significantly higher than 5.60 in the internal control group and 5.10 in the external control group. The median value of OTM was 3.80 in the exposure group, significantly higher than 1.50 in the internal control group and 2.00 in the external control group.Mean cell positive was 31.2% in the exposure group, significantly higher than 17.4% in the internal control and 19.6% in the external control groups.Cell positive (%) was significantly correlated with tail DNA percentage and with OTM of whole subjects (n=63). Conclusions:Results showed that occupational FE exposure is associated with an increase in sperm DNA damage.A combination of the Comet and TUNEL assays would offer more comprehensive information for a better understanding of sperm DNA damage,and the biological significance of sperm DNA damage in sperm function and male infertility.

Fenvalerate,a synthetic pyrethroid,is widely used in agriculture and other domestic applications in China.Recently,Fenvalerate has been suspected to be one of the endocrine-disrupting chemicals(EDC).In this study, we investigated the effects of fenvalerate on follicle-stimulating hormone(FSH)-stimulated progesterone (P4) production by human ovarian luteinizing-granulosa cells (hGLCs). After 24 h incubation,fenvalerate inhibited FSH-stimulated P4 production.At the same time, FSH-stimulated cAMP also decreased.Due to calcium and Ca2+-calmodulin (CaM) system involving gonadotropin-stimulated steroidogenesis by granulosa cells,we then evaluated the effects of fenvalerate on trifluoperazine (TFP)-and verapamil-driven FSH-stimulated P4 production.The results showed that calcium or calmodulin might play a role in fenvalerate-induced alterations in FSH-stimulated P4 biosysthesis.Then,the effects of fenvalerate on calcium homeostasis in hGLCs were studied. The result showed that 5μM fenvalerate induced a slow increase in[Ca2+] in hGLCs by using a fluorescent Ca2+ indicator fluo-3/AM. The changes in total concentration of CaM in hGLCs induced by fenvalerate were evaluated by a method of immunofluorescence. There is a significant increase in all treated groups.In summary, fenvalerate could inhibit FSH-stimulated P4 production. Also, fenvalerate interferes with calcium homeostasis in hGLCs. The effects of fenvalerate on FSH-stimulated ovarian steroidogenesis may be mediated partly through calcium signal.

Fenvalerate,a synthetic pyrethroid insecticide,is widely produced and used worldwide.To explore fenvalerate-induced genotoxic effects, particularly numerical chromosome aberration (CA),we firstly examined conventional semen parameters, the progression and motion parameters of the spermatozoa among 12 fenvalerate-exposed workers and 30 donors of the internal and external control groups.Then numerical CA of chromosome X,Y and 18 were investigated by multicolor fluorescence in situ hybridization (FISH).The results showed the significant differences in the percentage of sperm abnormality between fenvalerate-exposed group and the external control group (P=0.024).In aneuploid parameters,the frequency (mean