title: [Effects of SNP and L-NAME on spermatogenesis in rats].
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  Enhancing ectogenous NO will suppress spermatogenesis while inhibiting NO productive pathway will promote it.
authors.affiliation: Department of Histology and Embryology, Nanhua University, Hengyang, Hunan 421001, China.
authors.forename: Meixiang
authors.initials: M
authors.lastname: Li
authors.forename: Liping
authors.initials: L
authors.lastname: He
authors.forename: Yuanjie
authors.initials: Y
authors.lastname: Xie
authors.forename: Nan
authors.initials: N
authors.lastname: Wen
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Zhang
authors.forename: Yueshun
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000818:Animals; D004247:DNA / Q000032:analysis; D005434:Flow Cytometry; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D009569:Nitric Oxide / Q000502:physiology; D009599:Nitroprusside / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013091:Spermatogenesis / Q000187:drug effects*
chemical_list: D009599:Nitroprusside; D009569:Nitric Oxide; D004247:DNA; D019331:NG-Nitroarginine Methyl Ester