No abstract

In this study the effect of bendiocarb on the rabbit testicular structure and spermatozoa motility was investigated. For testicular structure evaluation the animals were fed with bendiocarb tablets daily at a dose of 5 mg/kg of body weight for 13 days. The relative volume of the germinal epithelium, interstitium and lumen was measured. The testicular structure evaluation showed decreased relative volume of germinal epithelium in both experimental groups in comparison with the control group. The relative volume of the interstitium was increased in both experimental groups. An increase of the relative volume of the lumen was registered also in both experimental groups. Qualitative analysis detected a dilatation of blood vessels in the interstitium, undulation of the basal membrane and some empty spaces in the germinal epithelium after bendiocarb administration. The spermatozoa motility was evaluated by the computer assisted semen analyzer (CASA) method in various time intervals (0-180 minutes) and the bendiocarb concentration in the culture medium added to experimental groups varied from 0.054 to 0.268 mg/mL. Spermatozoa motility and progressive motility significantly decreased with increased bendiocarb administration and with extending the period of incubation. For other fine motility parameters, a decrease dependent on the time of incubation and on the bendiocarb concentration almost in all experimental groups in comparison to the control was detected. These results clearly suggest that in vitro also in vivo bendiocarb administration decrease male fertility.

The present study was aimed at investigating the effect of nickel chloride (NiCl2) on secretion of progesterone (P), ultrastructure and apoptosis in porcine granulosa cells. NiCl2 was added to the cells to achieve a Ni(2+) concentration of 62.5, 125, 250, 500 and 1,000 μmol/L. A control group contained no NiCl2 addition. Quantification of P was performed directly from aliquots of the media from control and treated porcine granulosa cells after 48 h of culture using radioimmunoassay. Quantification of apoptotic cells was performed using terminal deoxynucleotidyl transferase dUTP nick end labelling assay, and ultrastructural changes were analyzed using transmission electron microscopy. A concentration-dependent depletion of P production was observed significantly for 1,000 μmol/L NiCl2. The percentage of apoptotic cells was increased in all experimental groups significantly only after addition of 1,000 μmol/L NiCl2. After addition of ≥250 μmol/L NiCl2, a higher incidence of euchromatin was observed. Also, lipid droplets and vacuoles in the cytoplasm increased after addition of ≥250 μmol/L NiCl2. NiCl2 induced the decrease in numbers of mitochondria and smooth endoplasmic reticulum after treatment with ≥500 μmol/L NiCl2. Our findings suggest a negative effect of NiCl2 on steroidogenesis and apoptosis as well as ultrastructure of porcine granulosa cells.

ABSTRACT:The aim of this in vitro study was to determine the effect of lead chloride (PbCl 2 ) on rabbit spermatozoa motility and morphology. Lead concentrations in the medium ranged between 0.45 and 11.17 μg/ml; incubation time was 240 min (analyzed immediately after Pb addition followed by 30, 60, 120, 180, and 240 min), and temperatures of the culture environment were 22°C (laboratory), 4°C (refrigerator), and 37°C (incubator). Results were compared with a control group without Pb addition. After 30 min of culture at 22°C, a negative effect of Pb was noted as spermatozoa motility significantly decreased in groups with higher concentrations. After 120 and 240 min, a dose-dependent effect on spermatozoa motility was noted. At 4°C, spermatozoa motility analysis detected no significant differences between any of the experimental groups and control. At 37°C, a negative effect of Pb incubation on motility was detected at Times 30, 60, 120, 180, and 240 in groups with high concentrations. At Times 120, 180, and 240 a significant decrease in spermatozoa motility was also noted in all experimental groups in comparison to control. The analysis of pathological spermatozoa at Time 240 revealed an increasing trend of morphological abnormalities after incubation with Pb. Across three temperature regimes an increase of morphological changes was noted, particularly in the group with the highest Pb concentration. The predominant morphological abnormalities were knob twisted flagellum, flagellum ball, separated flagellum, and broken flagellum. Knob twisted flagella represented the most frequent pathological changes in the experimental group with the highest Pb concentration. Results suggest that the inhibitory effect of Pb on spermatozoa motility parameters depends on the concentration, incubation time, as well as environmental temperature during incubation. Furthermore, a negative effect of Pb in vitro on spermatozoa morphology indicates possible reproductive problems under in vivo conditions, too.

In this study distribution of nickel as a risk factor of environment in testis and its effects on the testicular structure in experimental animals and effect on spermatozoa was analyzed. In this study the effect of Ni on the testicular structure after an experimental intraperitoneal (i.p.) administration, concentration of nickel in semen of different animal species and the effect of in vitro spermatozoa incubation with nickel on the spermatozoa motility and membrane changes is reported. Our findings clearly suggest a negative effect of nickel on the structure as well as on the function of seminiferous epithelium. In experimental groups with nickel a significant (p<0.001) decrease of germinal epithelium in comparison with control group was observed. The analysis of nickel showed that the concentration of this element in stallion semen was 0.20 mg/kg, in bull 0.12 mg/kg, ram 0.31 mg/kg, boar 0.06 mg/kg and in fox semen 0.36 mg/kg. Concentrations from 125 μM Ni/ml in various time periods of culture stimulate spermatozoa motility after 30 minutes (p<0.001), but later inhibit spermatozoa motility. After a culture of spermatozoa with addition of 125 µM Ni/ml and 240 minutes a typical Annexin-V fluorescence reaction was detected. Fluorescence was detected in mitochondrial segment of bovine spermatozoa. In spermatozoa exposed to higher nickel concentration the Annexin-V positive reaction was detected also on the spermatozoa head membrane. Nickel in very low concentrations (7.8 μM Ni/ml) stimulates the spermatozoa motility but in higher concentrations (>250 μM Ni/ml) cause decrease of spermatozoa motility in vitro.