title: Bisphenol A, Dichlorodiphenyltrichloroethane (DDT) and Vinclozolin Affect ex-vivo Uterine Contraction in Rats via Uterotonin (Prostaglandin F2α, Acetylcholine and Oxytocin) Related Pathways.
abstract: Bisphenol-A (BPA), dichrolodiphenyltrichloroethane (DDT) and vinclozolin were found able to induce abnormal uterine contraction. The mechanisms involved remains unclear. We hypothesized that the effect of these compounds were mediated via the uterotonin pathways. Therefore, in this study, effects of BPA, vinclozolin and DDT-only and in combination with uterotonins (PGF-2α, acetylcholine and oxytocin) on the force and pattern of uterine contraction were observed.
  
  
  METHODS
  Uteri were harvested from intact adult female rats 24 hours after a single injection (1 mg/kg/b.w) of estrogen to synchronize their oestrous cycle. The uterine horns were subjected for ex-vivo contraction studies in an organ bath connected to Powerlab data acquisition system. Different doses of BPA, vinclozolin and DDT were added into the bathing solution and changes in the pattern and strength of uterine contraction were recorded. Further, increasing doses of uterotonins were concomitantly administered with these compounds and changes in the force and pattern of contraction were observed.
  
  
  RESULTS
  In the absence of uterotonins, uterine contractile force decreased with increasing doses of BPA and DDT. However, vinclozolin induced sharp increase in the contractile forces which then gradually decrease. Administration of BPA, DDT and vinclozolin alone reduced the force of uterine contraction following stimulation of contraction by uterotonins. However, BPA, vinclozolin or DDT effects were relieved upon co-administration with uterotonins at increasing doses.
  
  
  CONCLUSIONS
  The antagonizing effect of uterotonins on BPA, vinclozolin and DDT actions could explain the mechanism underlying the adverse effect of these compounds on uterine contraction.
authors.affiliation: 1. Department of Physiology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia;
authors.forename: Naguib
authors.initials: N
authors.lastname: Salleh
authors.affiliation: 1. Department of Physiology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia; ; 2. Department of Biomedical Science, Faculty of Health and Life Sciences, Management and Science University, Shah Alam, 40100 Selangor Darul Ehsan, Malaysia.
authors.forename: Nelli
authors.initials: N
authors.lastname: Giribabu
authors.affiliation: 1. Department of Physiology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia;
authors.forename: Angeline Oh Mei
authors.initials: AO
authors.lastname: Feng
authors.affiliation: 1. Department of Physiology, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia;
authors.forename: Kyaimon
authors.initials: K
authors.lastname: Myint
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D003634:DDT / Q000494:pharmacology*; D015237:Dinoprost / Q000494:pharmacology*; D005260:Female; D010080:Oxazoles / Q000494:pharmacology*; D010121:Oxytocin / Q000494:pharmacology*; D010636:Phenols / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction; D014590:Uterine Contraction / Q000187:drug effects*; D000098826:Bisphenol A Compounds
chemical_list: D000109:Acetylcholine; D001559:Benzhydryl Compounds; D002118:Calcium; D003634:DDT; D015237:Dinoprost; D010080:Oxazoles; D010121:Oxytocin; D010636:Phenols; C025643:vinclozolin; C006780:bisphenol A; D000098826:Bisphenol A Compounds
keywords: DDT; bisphenol A; uterine contractility; uterotonins.; vinclozolin