title: [The concentration of HO-2 and CO in rat penile tissue of different ages].
abstract: OBJECTIVE
  To compare the distribution of heme oxygenase-2 and concentration of carbon monoxide in rat penile tissue of 8, 16 and 24 months and investigate the relationship between the system of HO-2/CO and aging.
  
  
  METHODS
  Using SABC immunohistochemistry staining, image analysis system and the method of carboxyhemoglobin standard curve, the distribution of heme oxygenase-2 and concentration of carbon monoxide in different month rat penile tissues were investigated.
  
  
  RESULTS
  The penile arteries were surrounded by HO-2 positive cells, which were also seen in the trabecular meshwork of smooth muscle. Compared with other part of penile, the penile arteries adventitia and the endothelial cells of cavernous exhibited darker staining. With the increasing of rat's living month the staining of penile tissues turned faint and the concentration of carbon monoxide in tissue decreased( P < 0.05 ). The imaging analysis system showed that the older the rat was the less HO-2 positive compositions contained (P < 0.05).
  
  
  CONCLUSIONS
  With aging the decreasing concentration of HO-2 leads to the downfgt-regulation in rat penile tissue.
authors.affiliation: Tianjin Institute of Urology, Tianjin 300211, China. dragon-hu@hotmail.com
authors.forename: Hai-Long
authors.initials: HL
authors.lastname: Hu
authors.forename: Rui-Fa
authors.initials: RF
authors.lastname: Han
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D002248:Carbon Monoxide / Q000032:analysis / Q000378:metabolism*; D015536:Down-Regulation; D006419:Heme Oxygenase (Decyclizing) / Q000032:analysis / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D010413:Penis / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013194:Staining and Labeling
chemical_list: D002248:Carbon Monoxide; D006419:Heme Oxygenase (Decyclizing); C105245:heme oxygenase-2