Experimental varicocele was induced by partial ligation of the left renal vein in rats, and the effect of thymosin (fraction 5), a hormone secreted by the thymus, on the level of cyclic nucleotides was investigated. The levels of cAMP and cGMP in plasma and testicular tissue were estimated using radioimmunoassay techniques. The results showed that the level of cAMP in bilateral testicular tissues in rats with experimental varicocele decreased considerably, especially in the left testicular tissue as compared with that in the control group (P<0.05). 4 weeks after thymosin administration (0.5 mg/rat, twice a week), the level of cAMP in bilateral testicular tissues rose significantly, as compared with that in the experimental varicocele group (P<0.01). These findings indicate that there exists imbalance in the metabolism of cyclic nucleotides in rats with experimental varicocele. This suggests that the abnormal level of cyclic nucleotides is one of the causes of infertility with varicocele. Since thymosin participates in the metabolism and regulation of cyclic nucleotides, it may have a direct or an indirect effect on the growth and function of reproductive cells.
An oxine modified electrode is prepared qn the basis of carbon paste. The process is rapid and simple. The catalytic stripping voltammetric characteristic of Cu (II) on the modified electrode was studied and the method has been applied to the determination of trace Cu (II), and there was good linear relationship between the concentration of Cu (II) and the peak height in the concentration range of 1.5 x 10−9−1.5 × 10−6 mol/L for Cu (II). We have detected the copper content of human hair and blood with satisfactory results. Moreover, the reaction mechanism of the modified electrode was discussed. It was found that the improvement of sensitivity and selection of the modified electrode was dependent of the complex adsorbing property of the electrode surface and the sensitive catalytic hydrogen wave produce.