Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Impacts of synthetic oestrogen and antioestrogen treatments on courtship and mating behaviours in male guppies (Poecilia reticulata)
Stockholm University, Faculty of Science, Department of Zoology. (HOL)
Södertörns högskola. (HOL)
(English)Manuscript (Other academic)
Abstract [en]

Understanding the neuroendocrinological mechanisms behind reproductive behaviour is fundamental when studying endocrine disruption. Neuroestrogen production is a key step in the activation of reproductive behaviours among vertebrates. The actions of estrogens are transmitted through estrogen receptors (ERs) in distinct brain nuclei. Here we report alterations in reproductive behaviours in guppy males following 55-day food treatments with the antiestrogen fulvestrant (ICI) and the synthetic oestrogen 17α-ethinylestradiol (EE2). Male courtship and mating attempts were severely reduced in EE2 treated males after both 27-30 and 41-55 days of treatment when paired with females. ICI treatment gave a significant reduction in the frequency of sigmoid display behaviour after 27-30 days of treatment, and an almost 2.5-fold increase in gonopodium thrusting after 41-55 days of treatment. ICI treated males also decreased their frequency in successful mating attempts in comparison to the control males. The neurological effects of ICI were confirmed by Real Time-PCR analysis for brain aromatase and ERα gene expression. ICI treatment suppressed aromatase expression to 64% and stimulated ERα gene expression by over 300%. These results indicate that oestrogen action via ERs may play an important role for the complete display of male courtship and mating behaviour in the guppy. The results also suggest that local steroids are involved in regulating brain aromatase expression and that the negative effects of EE2 on sexual behaviour are linked via endocrine disruption of gonadal function.

Keyword [en]
Brain aromatase, estrogen receptors, xenoestrogens, teleost reproduction, fulvestrant
National Category
Zoology
Research subject
Functional Zoomorphology
Identifiers
URN: urn:nbn:se:su:diva-26903OAI: oai:DiVA.org:su-26903DiVA: diva2:211717
Projects
Aromatase and androgens in fish reproductive behaviour
Available from: 2009-04-20 Created: 2009-04-17 Last updated: 2010-01-14Bibliographically approved
In thesis
1. Brain Aromatase in the guppy, Poecilia reticulata: Distribution, control and role in behaviour
Open this publication in new window or tab >>Brain Aromatase in the guppy, Poecilia reticulata: Distribution, control and role in behaviour
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Oestrogens are produced by aromatisation of androgens by the aromatase enzyme. In the vertebrate brain this synthesis has vital functions in nerve protection, cell proliferation and nerve development during injury respectively brain development. Brain oestrogens are also crucial in activating certain reproductive and aggressive behaviours in mammals and birds. Teleosts have remarkably high activity of brain aromatase (bAA) compared to mammals and birds; 100-1000 times higher in brain regions like the hypothalamus, pre-optic area and optic tectum. The role of brain oestrogens in teleost behaviour is, however, less clear than in e.g. songbirds and rodents. This thesis studies the potential role of brain aromatase and brain oestrogens in the reproductive behaviour of the guppy male (Poecilia reticulata), how guppy brain aromatase responds to steroids and is distributed in the adult brain.

The thesis shows that male behaviour can be affected by brain aromatase. Reduction of bAA by aromatase inhibitor treatment reduced the sexual behaviours sigmoid display and gonopodium swinging (I) and oestrogen receptor blocking with an oestrogen antagonist reduced the number of successful mating attempts (II). The anatomical study (IV) showed that brain aromatase is distributed in areas of the adult guppy brain that are connected to reproductive control and behaviour in vertebrates.

Guppy bAA is stimulated by both androgens and oestrogens (III) but is more sensitive to oestrogens, especially in males, and could thus be used as an indicator of endocrine disruption at low concentrations found in the environment.

The thesis can also conclude that females possess more brain aromatase than males, and that although it is expressed in the same pattern throughout the brain in both genders the enzymatic activity is differently distributed between the sexes.

Place, publisher, year, edition, pages
Stockholm: Department of Zoology, Stockholm University, 2009. 41 p.
Series
Södertörn Doctoral Dissertations, ISSN 1652-7399 ; 36
Keyword
Oestrogen production, behaviour, anatomy, endocrinology, bio markers, endocrine disruption
National Category
Microbiology
Research subject
Functional Zoomorphology
Identifiers
urn:nbn:se:su:diva-26942 (URN)978-91-86069-03-2 (ISBN)978-91-7155-870-1 (ISBN)
Public defence
2009-05-26, MA624, Södertörns högskola, Alfred Nobels allé 7, Huddinge, 10:00 (English)
Opponent
Supervisors
Projects
Aromatase and androgens in fish reproductive behaviour
Available from: 2009-05-05 Created: 2009-04-20 Last updated: 2009-06-09Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Hallgren, Stefan
By organisation
Department of Zoology
Zoology

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 114 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf