title: [Nicotine- and tar-free cigarette smoke extract reduces the penile erectile function of rats].
abstract: OBJECTIVE
  To evaluate the impact of nicotine- and tar-free cigarette smoke extract (fCSE) on the serum testosterone (T) level and erectile function of male rats.
  
  
  METHODS
  We randomized 30 male SD rats to three groups of equal number to receive subcutaneous injection of PBS (1.0 ml / 300 g body weight per day), fCSE (1.0 ml/300 g body weight per day), and reduced glutathione hormone (GSH, 200 mg per kg body weight per day) in addition to fCSE (fCSE + GSH), respectively, all for 8 weeks. Then we evaluated the erectile function of the rats by measuring the maximal intracavernous pressure (MICP), mean arterial pressure (MAP), ICP/MAP ratio, time of stimulation to MICP (Tmax), and cavernosal filling fate (CFR). We determined the serum T level, the activities of superoxide dismutase (SOD) , malondialdehyde (MDA), and nitric oxide synthase (NOS) in the cavernosal tissue, and also observed the morphological changes of the corpus cavernosum.
  
  
  RESULTS
  Compared with the controls, the rats of the fCSE group showed obvious decreases in the levels of serum T ([5.37 ± 1.43] vs [3.22 ± 1.11] μg/L), NOS ([2.90 ± 0.27] vs [1.67 ± 0.18] U/mg) , and SOD ([18.41 ± 1.09] vs [13.36 ± 1.18] U/mg prot) and erectile function-related indexes MICP ([85.92 ± 6.36] vs [58.99 ± 10.76] mmHg), MICP/MAP (0.86 ± 0.09 vs [0.56 ± 0.08]), and CFR (2.14 ± 0.44 vs 0.89 ± 0.44), but markedly increased Tmax ([29.90 ± 5.78] vs [42.90 ± 8.56]s), with a positive correlation between the serum T level and CFR (r = 0. 364, P < 0.05). Masson staining revealed a lower ratio of the corpus cavernosum smooth muscle tissue to collagen fiber in the fCSE group (0.27 ± 0.04) than in the control (0.98 ± 0.12). Compared with the fCSE group, the fCSE + GSH group exhibited significantly improved MICP ([58.99 ± 10.76 ] vs [77.95 ± 7.71] mmHg), MICP/MAP (0.56 ± 0.08 vs 0.77 ± 0.09), and CFR (0.89 ± 0.44] vs 1.76 ± 0.42) and shortened Tmax ([42.90 ± 8.56 ] vs [32.10 ± 5.84 ] s). The ratio of the corpus cavernosum smooth muscle tissue to collagen fiber was higher in the fCSE + GSH than in the fCSE group (0.77 ± 0.09 vs 0.27 ± 0.04) but still lower than in the control (0.98 ± 0.12).
  
  
  CONCLUSIONS
  Nicotine- and tar-free cigarette smoke extract reduces the serum T level and erectile function of rats, which is related to oxidative stress. Antioxidant therapy can improve erectile function but has a limited value for morphological protection of the penile tissue.
authors.forename: Shu-chao
authors.initials: SC
authors.lastname: Liu
authors.forename: Tian-peng
authors.initials: TP
authors.lastname: Wu
authors.forename: Qi-xin
authors.initials: QX
authors.lastname: Duan
authors.forename: Ling-qi
authors.initials: LQ
authors.lastname: Liu
authors.forename: Chao
authors.initials: C
authors.lastname: Song
authors.forename: Wen-biao
authors.initials: WB
authors.lastname: Liao
authors.forename: Si-xing
authors.initials: SX
authors.lastname: Yang
mesh_terms: D000818:Animals; D007172:Erectile Dysfunction / Q000139:chemically induced*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009130:Muscle, Smooth / Q000473:pathology; D009538:Nicotine; D019001:Nitric Oxide Synthase / Q000378:metabolism; D010410:Penile Erection / Q000187:drug effects*; D010413:Penis / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012906:Smoke / Q000009:adverse effects*; D013482:Superoxide Dismutase / Q000378:metabolism; D013638:Tars; D014026:Nicotiana / Q000009:adverse effects*
chemical_list: D012906:Smoke; D013638:Tars; C024746:tobacco tar; D008315:Malondialdehyde; D009538:Nicotine; D019001:Nitric Oxide Synthase; D013482:Superoxide Dismutase