Effects of SNP and L-NAME on spermatogenesis in rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To observe the effects of nitric oxide(NO) on the DNA ploidy of germ cells and to evaluate the role of NO in modulating spermatogenesis by using SNP, a donor of NO and N-nitro-l-arginine-mythel-ester(L-NAME), an inhibitor of nitric oxide synthese(NOS) in rats physically in vivo.</p><p><b>METHODS</b>Forty adult male, Sprague-Dawley rats (60-70 days) were divided into four groups, and injected ultraperitoneally with one of the following agents (once a day, for 12 days): SNP, L-NAME and SNP + L-NAME with normal saline. Two hours after the last injection the rats were sacrificed. The sera were collected and stored at -70 degrees C for subsequent hormone assay. The concentration of serum testosterone was measured by radioimmunoassay. Serum NOx- (nitrite/nitrate) concentration was measured by Greiss method. DNA of spermatogenic cells was detected by flow cytometry(FCM), and the percentage of 1c, 2c and 4c germ cells calculated.</p><p><b>RESULTS</b>In the SNP treatment group, the serum concentration of NOx- was higher, testosterone concentration was lower and the number of 1c cells was smaller compared with the control group. However, in rats treated with L-NAME, the concentration of NOx- was significantly lower, testosterone concentration was higher and the number of 1c cells was larger compared with the control group(P < 0.01). No changes were observed in the SNP + L-NAME group.</p><p><b>CONCLUSION</b>Enhancing ectogenous NO will suppress spermatogenesis while inhibiting NO productive pathway will promote it.</p>

The effect and mechanism of caveolin-1 upregulation on the proliferation of MGC803 cell line / 中国医师杂志

Objective To study the effect of caveolin-1 gene expression on the proliferation of human gastric adenocarcinoma cells,and to explore the possibility for its future usage in gene therapy.Methods The full-length caveolin-1 gene was stably transfected into the MGC803 cell line by lipofectin.The Pcl neo vector was transfected at the same time as mock control.The expression of caveolin-1 was detected by Western blot in both the caveolin-1 gene transfected MGC803 cells and the controls.The cell cycle was analyzed by flow cytometry.Results After transfected with caveolin-1,MGC803 cells significantly up-regulated the expression of caveolin 1 and extended their doubling time.The cell proliferation was inhibited and the cell cycle was arrested in the G_0/G_1 phase.Conclusion Caveolin-1 can inhibit the proliferation of MGC803 cells and induce cell cycle arrest in G_0/G_1 phase.

EFFECT OF SODIUM NITROPRUSSIDE AND N-NITRO-L-ARGININE-MYTHEL-ESTER ON APOPTOSIS OF SPERMATOGENIC CELLS IN RAT TESTIS / 解剖学报

Objective To evaluate the effect of sodium nitroprusside(SNP)and N-nitro-l-arginine-mythel-ester (L-NAME) on apoptosis of spermatogenic cells in rats. Methods Fourty adult male Sprague-Dawley rats (60-70days) were divided into four groups.Each group was injected intraperitoneally with one of the following agents, once a day, for 12 days: 1. SNP; 2.L-NAME;3.SNL+L-NAME;4.Normal saline NS group.Two hours after the last time injection the rats were sacrificed.TUNEL staining and flow cytometry analysis were used to detect the apoptosis of spermatogenic cells. Results Sub-monoploid and apoptosis index (AI) in SNP group was significantly higher than that of NS group and sub-monoploid and apoptosis index (AI) in L-NAME group were significantly lower than that of NS group by FCM and TUNEL (P0.5) was found.Conclusion SNP can accelerate the apoptosis of spermatogenic cells and L-NAME can inhibite the apoptosis of spermatogenic cells,The effect of SNP and L-NAME on apoptosis of spermatogenic cells probably occurs through the action of nitric oxide.