title: Effects of Estrogen Receptor Modulators on Morphine Induced Sensitization in Mice Memory.
abstract: OBJECTIVE
  In this study, the effects of estradiol valerate and raloxifenea selective estrogen receptor modulator; (SERM) on morphine induced sensitization were examined in mice memory, according to the step-down passive avoidance task.
  
  
  METHODS
  The mice received morphine or estradiol and raloxifene for three days alone or in combination with morphine. After a drug free period of 5 days, the subjects received saline or morphine as pre- training treatments followed by a pre-test saline administration. The memory retrieval was evaluated using step-down passive avoidance test both on the training and test day.
  
  
  RESULTS
  The results illustrated that the three- day administration of morphine induced sensitization through the enhancement of memory retrieval (morphine induced sensitization in mice memory). Both the three- day administration of estradiol valerate alone and with morphine (5 mg/kg) restored memory. On the other hand, the three- day administration of raloxifene had no effect on memory retrieval alone, but declined morphine induced sensitization in mice memory.
  
  
  CONCLUSIONS
  The results of the study indicated that there is an interaction between estrogen receptor modulators and morphine induced sensitization in mice memory.
authors.affiliation: Department of Pharmacology and Toxicology, School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran.
authors.forename: Mahdieh
authors.initials: M
authors.lastname: Anoush
authors.affiliation: Department of Pharmacology and Toxicology, School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Jani
authors.affiliation: Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Moosa
authors.initials: M
authors.lastname: Sahebgharani
authors.affiliation: Department of Physiology and Pharmacology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Jafari
keywords: Estradiol Valerate; Memory; Opioids; Raloxifene; Sensitization; Step-Down