title: [Expression of nNOS and ultrastructural changes in the penile tissue of rats with prolactinoma-induced erectile dysfunction].
abstract: OBJECTIVE
  To study the expression of nNOS and ultrastructural changes in the penile tissue of rats with prolactinoma-induced erectile dysfunction (ED).
  
  
  METHODS
  We established the model of prolactinoma in 20 male Westar rats by peritoneal injection of diethylstilbestrol (DES) and treated the control rats with normal saline (n = 10) or sterilized arachis oil (n = 10). After 8 weeks, we performed the apomorphine test and measured the weight of the pituitary gland and the levels of serum prolactin (PRL) and testosterone (T) to confirm the successful construction of the prolactinoma-induced ED model. Then we determined the expression of nNOS in the penile tissue by immunohistochemistry and examined the ultrastructural changes of the penile cavernosum under the transmission electron microscope.
  
  
  RESULTS
  The prolactinoma-induced ED model was successfully established in 15 rats. The weight of the pituitary gland was significantly increased in the rats treated with DES as compared with the normal saline and sterilized arachis oil controls ([46.7 ± 15.5] vs [11.7 ± 2.4] and [12.4 ± 2.3] mg, both P < 0.05). The level of serum PRL was markedly higher while that of T remarkably lower in the former than in the latter two groups ([1,744.9 ± 304.5] vs [11.5 ± 2.4] and [10.6 ± 1.9] ng/ml, both P < 0.0l; [1.54 ± 0.46] vs [3.11 ± 1.08] and [3.04 ± 1.11] ng/ml, both P < 0.05). The rate of penile erection was significantly reduced in the prolactinoma-induced ED model rats in comparison with the normal saline and arachis oil controls (16.7% vs 100% and 87.5%, both P < 0.05), and so was the expression of nNOS in the penile tissue (0.024 ± 0.011 vs 0.066 ± 0.019 and 0.058 ± 0.021, both P < 0.05). Transmission electron microscopy manifested significant ultrastructural changes in the endothelial and smooth muscle cells of the cavernous tissue in the prolactinoma-induced ED models.
  
  
  CONCLUSIONS
  The ultrastructural changes of the penile cavernous tissue and the reduced expression of nNOS in penile tissue may be the most important mechanisms of prolactinoma-induced ED in rats.
authors.forename: Bo-wen
authors.initials: BW
authors.lastname: Weng
authors.forename: Si-chuan
authors.initials: SC
authors.lastname: Hou
authors.forename: Hai
authors.initials: H
authors.lastname: Zhu
authors.forename: Luo
authors.initials: L
authors.lastname: Xu
authors.forename: Xiao
authors.initials: X
authors.lastname: Luan
authors.forename: Hai-yan
authors.initials: HY
authors.lastname: Qi
authors.forename: Wei-min
authors.initials: WM
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Li-jiang
authors.initials: LJ
authors.lastname: Sun
mesh_terms: D000818:Animals; D001058:Apomorphine; D002273:Carcinogens; D004054:Diethylstilbestrol; D007172:Erectile Dysfunction / Q000209:etiology*; D006801:Humans; D008297:Male; D032389:Myocytes, Smooth Muscle / Q000648:ultrastructure; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D009929:Organ Size; D010410:Penile Erection; D010413:Penis / Q000201:enzymology* / Q000648:ultrastructure; D010911:Pituitary Neoplasms / Q000139:chemically induced / Q000150:complications*; D011388:Prolactin / Q000097:blood; D015175:Prolactinoma / Q000139:chemically induced / Q000150:complications*; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000097:blood
chemical_list: D002273:Carcinogens; D013739:Testosterone; D004054:Diethylstilbestrol; D011388:Prolactin; C496320:NOS1 protein, human; D052248:Nitric Oxide Synthase Type I; D001058:Apomorphine