Sex differences and the effects of estrogen on cell proliferation, cell death and behaviour due to acute and repeated predator odour stress in adult rats
department or school: Medicine, Faculty of
data provider: DSpace
degree campus: UBCV
creator: Falconer, Erin Michelle
issued: 2009-08-20T21:14:40Z
issued: 2002
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Possible sex differences in response to predator odour exposure were examined in adult rats. The first study measured behaviour, cell proliferation, and survival in the dentate gyrus of adult males and females in response to acute and repeated trimethyl thiazoline (TMT, the main component of fox feces) or control odour exposure. Rats were injected with one of the cell synthesis markers bromodeoxyuridine (BrdU) or [³H] thymidine and perfused 24 hours (cell proliferation) after an acute TMT exposure or after 5 days (cell survival) of repeated TMT exposure. After acute exposure, cell proliferation and death were suppressed in TMT-exposed males compared to control males, but not in females. Repeated TMT exposure in males increased cell death and increased the survival of new cells born on Day 1 of exposure. Males initially expressed more defensive behaviours in response to TMT but this expression habituated after repeated TMT exposure. This habituation was concurrent with enhanced new cell survival, possibly indicating that learning enhanced new cell survival. In a second study, we assessed whether ovarian hormones altered the response to acute TMT exposure in females. Ovariectomized (OVX) females were given either a high dose of estradiol (EB) or a low dose of estradiol and progesterone followed by a high dose of estradiol (EB-P). TMT exposure did not affect cell proliferation in any group. However, hormone treatment affected the behavioural, hormonal, and cell death response to TMT. EB increased cell proliferation and decreased defensive behaviour whereas EB-P decreased cell proliferation and increased defensive behaviour. Thus, we demonstrated that pre-treatment with a low dose of estradiol and progesterone profoundly affected the behavioural and cellular response to later administration of estradiol. Taken together, acute TMT exposure suppressed both cell proliferation and death while repeated TMT exposure enhanced new cell survival and cell death in males. However,…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/12461
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note: SEX DIFFERENCES AND THE EFFECTS OF ESTROGEN ON CELL PROLIFERATION, CELL DEATH AND BEHAVIOUR DUE TO ACUTE AND REPEATED PREDATOR ODOUR STRESS IN ADULT RATS by ERIN MICHELLE FALCONER B. Sc., The University of British Columbia, 1999 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE STUDIES (Neuroscience Programme) We accept this thesi/as conibpfiing to the required standard THE UNIVERSITY OF BRITISH COLUMBIA April 2002 © Erin Michelle Falconer, 2002 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Dejaartmenf^f G, Muu^rt- PtoG/Z/frin //V dLuicJ>SC\ isvcl The University of British Columbia Vancouver, Canada Date /h/M . DE-6 (2/88) 11 Abstract Possible sex differences in response to predator odour exposure were examined in adult rats. The first study measured behaviour, cell proliferation, and survival in the dentate gyrus of adult males and females in response to acute and repeated trimethyl thiazoline (TMT, the main component of fox feces) or control odour exposure. Rats were injected with one of the cell synthesis markers bromodeoxyuridine (BrdU) or [ H] thymidine and perfused 24 hours (cell proliferation) after an acute TMT exposure or after 5 days (cell survival) of repeated TMT exposure. After acute exposure, cell proliferation and death were suppressed in TMT-exposed males compared to control males, but not in females. Repeated TMT exposure in males increased cell death and increased the survival of new cells born on Day 1 of exposure. Ma…
has type: Thesis/Dissertation
date issued: 2002-11
is shown at: 10.14288/1.0090400
language: eng
degree discipline: Neuroscience
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/12461