title: Long-term effects of ageing and ovariectomy on aversive and recognition memory and DNA damage in the hippocampus of female rats.
abstract: OBJECTIVE
  This study investigated the influence of ageing - in particular the decrease of gonadal hormone levels during the ageing process - on the memory and the levels of DNA damage in the hippocampus of female rats.
  
  
  METHODS
  Three groups of female Wistar rats were investigated: Group I consisted of non-ovariectomised, adult animals (6 months old); Group II consisted of non-ovariectomised, aged animals (18 months old); and Group III consisted of ovariectomised, aged animals (18 months old). The memory of the animals in these groups was examined via novel object recognition and inhibitory avoidance tests. The hippocampus tissue samples of all animals were obtained via biopsy and used to quantify the DNA damage using a Comet Assay.
  
  
  RESULTS
  According to our findings, the process of ageing results in a change during the behavioural tests. To prevent genotoxic damage to the hippocampus caused by the ageing process, lowered hormone levels seem to be part of a protective biochemical mechanism in the body of rats. Animals that were previously submitted to an ovariectomy adapted better to these lower levels of hormones.
  
  
  CONCLUSIONS
  Our results indicate that ovariectomy can provide beneficial long-term effects on the memory. However, this could be specific to the kind of memory examined, as the aversive memory deficits caused by ageing were not affected by ovariectomy.
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology (LABIM), Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Daniela Dimer
authors.initials: DD
authors.lastname: Leffa
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology (LABIM), Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Adriani Paganini
authors.initials: AP
authors.lastname: Damiani
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology (LABIM), Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Daiane Dal Col
authors.initials: DD
authors.lastname: Damazio
authors.affiliation: 2 Laboratory of Neuroscience, Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Naiana Pereira
authors.initials: NP
authors.lastname: Guerra
authors.affiliation: 2 Laboratory of Neuroscience, Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Morgana
authors.initials: M
authors.lastname: Moretti
authors.affiliation: 2 Laboratory of Neuroscience, Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Geovana Gomes da Silva
authors.initials: GG
authors.lastname: de Brito
authors.affiliation: 2 Laboratory of Neuroscience, Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Carina Rodrigues
authors.initials: CR
authors.lastname: Boeck
authors.affiliation: 3 Laboratory of Behavioural Pharmacology, Postgraduate Programme of Behavioural Neuroscience, Centre for Biosciences, University Campus, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
authors.forename: Elaine Cristina
authors.initials: EC
authors.lastname: Gavioli
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology (LABIM), Postgraduate Programme of Health Sciences, Department of Health Sciences, University of Southern Santa Catarina, Criciúma, SC, Brazil.
authors.forename: Vanessa Moraes
authors.initials: VM
authors.lastname: de Andrade
mesh_terms: D000375:Aging / Q000235:genetics / Q000502:physiology* / Q000523:psychology; D000818:Animals; D004249:DNA Damage; D004958:Estradiol / Q000097:blood; D005260:Female; D006624:Hippocampus / Q000502:physiology*; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000502:physiology*
chemical_list: D004958:Estradiol