title: Expression of aquaporin proteins in vagina of diabetes mellitus rats.
abstract: BACKGROUND
  Aquaporins (AQPs) are membrane proteins that facilitate water movement across biological membranes. Vaginal lubrication may be mediated by blood flow and other potential mechanisms related to transudation of fluid. The most common female sexual dysfunction in diabetes is inadequate vaginal lubrication.
  
  
  OBJECTIVE
  To investigate the expression of AQP1-3 in vaginal tissue of diabetes mellitus rats.
  
  
  METHODS
  Female Sprague-Dawley rats (N = 20) were randomly divided into group A (12-week-old nondiabetic control, N = 5), group B (16-week-old nondiabetes control, N = 5), group C (12-week-old diabetes mellitus rats, N = 5), and group D (16-week-old diabetes mellitus rats, N = 5). Vaginal fluid was measured by fluid weight absorbed by cotton swabs after pelvic nerve electrostimulation and anterior vaginal tissue was dissected for determining the expression of AQP1-3 by immunohistochemical study and Western blot.
  
  
  METHODS
  The expression of AQP1-3 was determined in the vagina of diabetes mellitus rats by Western blot.
  
  
  RESULTS
  There are no significant differences in serum estradiol concentrations of rats among these groups (P > 0.05). Vaginal fluid was significantly lower in group C (2.7 ± 0.67 mg) and group D (2.5 ± 1.03 mg) than in group A (5.74 ± 1.23 mg) and group B (5.5 ± 1.08 mg) (P < 0.05), respectively. The protein expressions of AQP1-3 were significantly lower in group C (43.40 ± 4.83, 60.60 ± 12.80, and 59.60 ± 6.95) and group D (20.81 ± 2.86, 47.80 ± 11.43, and 54.20 ± 5.26) than in group A (116.62 ± 3.21, 110.81 ± 8.044, and 108.80 ± 4.97) and group B (122.12 ± 14.54, 111.21 ± 15.07, and 106.40 ± 4.16) (P < 0.05), respectively.
  
  
  CONCLUSIONS
  Decreased vaginal fluid in diabetes mellitus rats after electrostimulation may be partly due to estrogen-independent decreases of AQP1-3 in vaginal tissue.
authors.affiliation: Department of Cardiovascular Disease, Affiliated Hospital, Luzhou Medical College, Luzhou, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Pei
authors.forename: Jun
authors.initials: J
authors.lastname: Jiang
authors.forename: Rui
authors.initials: R
authors.lastname: Jiang
authors.forename: Fang
authors.initials: F
authors.lastname: Ouyang
authors.forename: Haifan
authors.initials: H
authors.lastname: Yang
authors.forename: Yong
authors.initials: Y
authors.lastname: Cheng
authors.forename: Zhongcai
authors.initials: Z
authors.lastname: Fan
mesh_terms: D000818:Animals; D051398:Aquaporin 1 / Q000032:analysis*; D051399:Aquaporin 2 / Q000032:analysis*; D051400:Aquaporin 3 / Q000032:analysis*; D015153:Blotting, Western; D003921:Diabetes Mellitus, Experimental / Q000473:pathology*; D004558:Electric Stimulation; D005260:Female; D007124:Immunoenzyme Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D014621:Vagina / Q000378:metabolism / Q000473:pathology*
chemical_list: C496022:Aqp1 protein, rat; C496025:Aqp2 protein, rat; C496029:Aqp3 protein, rat; D051399:Aquaporin 2; D051398:Aquaporin 1; D051400:Aquaporin 3