umu.sePublications
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
Studies of pharmacokinetic and pharmacodynamic properties of isoallopregnanolone in healthy women
Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynaecology.
Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynaecology.
Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynaecology.
Show others and affiliations
2009 (English)In: Psychopharmacology, ISSN 0033-3158, E-ISSN 1432-2072, Vol. 203, no 1, 85-98 p.Article in journal (Refereed) Published
Abstract [en]

Rationale  The pharmacokinetics and behavioral effects of isoallopregnanolone (3β-hydoxy-5α-pregnan-20-one) in women are not known. Objectives  Allopregnanolone (3α-hydoxy-5α-pregnan-20-one) is a well-known neurosteroid, acting via the GABAA receptor in the human brain. The naturally occurring progesterone metabolite isoallopregnanolone is the 3β-stereoisomer of allopregnanolone. Prior studies have concluded that isoallopregnanolone has no effect on the GABAA receptor. However, an antagonistic effect of isoallopregnanolone to allopregnanolone on the GABAA receptor has been shown in animal and in vitro studies. The purpose of this study was to evaluate the pharmacokinetics and behavioral effects of isoallopregnanolone in humans.

Materials and methods  Six healthy women were given three increasing doses of isoallopregnanolone intravenously in the follicular phase. Repeated blood samples for analyses of isoallopregnanolone and allopregnanolone concentrations were drawn. Saccadic eye movement variables, self-rated sedation, and mood rating scales were used during the test day. A Likert scale for prospective symptoms was used to measure daily fluctuations during the ongoing menstrual cycle.

Results  Exogenously administered isoallopregnanolone produced a dose-dependent increase in the serum concentration of isoallopregnanolone. In parallel, there was also a rise in the allopregnanolone concentration. There was a decrease in saccadic eye movement variables, but no effect was found on self-rated sedation or mood and no changes were seen in prospective symptoms during the menstrual cycle.

Conclusions  After administration of isoallopregnanolone at a cumulative dose of 0.20 mg/kg, no adverse effects were observed. There is a metabolism of isoallopregnanolone to allopregnanolone, most likely explaining the effects on the saccadic eye movements.

Place, publisher, year, edition, pages
2009. Vol. 203, no 1, 85-98 p.
Keyword [en]
Isoallopregnanolone, Neurosteroids, Pharmacokinetics, Pharmacodynamics, Women
National Category
Obstetrics, Gynecology and Reproductive Medicine
Identifiers
URN: urn:nbn:se:umu:diva-49365DOI: 10.1007/s00213-008-1372-8OAI: oai:DiVA.org:umu-49365DiVA: diva2:455421
Available from: 2011-11-10 Created: 2011-11-10 Last updated: 2017-12-08Bibliographically approved
In thesis
1. GABA-steroid effects in healthy subjects and women with polycystic ovary syndrome
Open this publication in new window or tab >>GABA-steroid effects in healthy subjects and women with polycystic ovary syndrome
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Alternative title[en]
GABA-steroid effects : in healthy subjects and women with polycystic ovary syndrome
Abstract [en]

Background: The progesterone metabolite allopregnanolone is involved in several clinical conditions in women, e.g. premenstrual dysphoric disorder. It is a very potent GABA-steroid with GABA-A receptor effects similar to other GABA-agonists, e.g. benzodiazepines, and it causes sedation. An objective way to examine effects on the GABA-A receptor in humans is to measure saccadic eye velocity (SEV), which is reduced by GABA-agonists, e.g. allopregnanolone. Animal studies suggest that allopregnanolone is involved in the regulation of gonadotropin secretion via the GABA-A receptor, but this has not been studied in humans. Polycystic ovary syndrome (PCOS) is the most common endocrine disturbance among women of fertile age (5–10%), characterized by polycystic ovaries, menstrual dysfunction, hyperandrogenity, and 50% have obesity. Studies have shown higher allopregnanolone levels in overweight people. PCOS women have increased levels of androstanediol, an androgen metabolite which is an GABA-A receptor agonist. Tolerance often occurs when persons are exposed to high levels of GABAergic modulators. It has not been studied whether GABA-A receptor sensitivity in PCOS women is changed. Another progesterone metabolite, isoallopregnanolone, is the stereoisomere of allopregnanolone but has not been shown to have any GABA-A receptor effect of its own. Instead it has often been used to control steroid specificity to allopregnanolone.

Aims: To compare the effects of allopregnanolone and isoallopregnanolone on gonadotropin secretion. To compare allopregnanolone levels, GABA-A receptor sensitivity to allopregnanolone and effects on gonadotropin secretion in both cycle phases and PCOS conditions. To examine pharmacokinetics and pharmacodynamic properties for isoallopregnanolone.

Method: In the follicular phase healthy women were examined for the effect of allopregnanolone or isoallopregnanolone on gonadotropin secretion. PCOS women and healthy women in both cycle phases were given allopregnanolone and the differences in effects on SEV were examined, as well as changes in serum levels of gonadotropins and allopregnanolone at baseline and during the test day. Pharmacokinetics and GABA-A receptor sensitivity using SEV were explored for isoallopregnanolone in healthy women.

Results: Allopregnanolone decreases gonadotropin serum levels in healthy controls in both cycle phases, but has no effect on gonadotropin secretion in women with PCOS. PCOS women have higher baseline serum levels of allopregnanolone than follicular phase controls, but lower levels than luteal phase controls. PCOS women show greater reduction in SEV to allopregnanolone than controls. Isoallopregnanolone has no effect on gonadotropin secretion. There is an effect of isoallopregnanolone on SEV, explained by a metabolism of isoallopregnanolone into allopregnanolone.

Conclusion: There are significant differences in the GABA-A receptor response to a GABA-steroid in different endocrine conditions in women of fertile age examined with saccadic eye velocity. The GABA-steroid allopregnanolone decreases gonadotropin serum levels in healthy women but not in PCOS women. The lack of effect on gonadotropins by isoallopregnanolone suggests an involvement of the GABA-A receptor.

Place, publisher, year, edition, pages
Umeå: Umeå University, 2011. 70 p.
Series
Umeå University medical dissertations, ISSN 0346-6612 ; 1455
Keyword
Allopregnanolone, isoallopregnanolone, gonadotropins, GABA-A receptor, women, polycystic ovary syndrome, saccade
National Category
Obstetrics, Gynecology and Reproductive Medicine
Research subject
Obstetrics and Gynaecology
Identifiers
urn:nbn:se:umu:diva-49375 (URN)978-91-7459-309-9 (ISBN)
Public defence
2011-12-02, Bergasalen, byggnad 27, Norrlands Universitets sjukhus, Umeå, 13:00 (Swedish)
Opponent
Supervisors
Available from: 2011-11-11 Created: 2011-11-10 Last updated: 2011-11-22Bibliographically approved

Open Access in DiVA

fulltext(1300 kB)389 downloads
File information
File name FULLTEXT02.pdfFile size 1300 kBChecksum SHA-512
44819ae8b80256d2a2e7c904c7d8965a59a64f220d440fbc447407dadd90cacaab423600a0a9f59de2e3f5b75ab878307d056e42cdf9af4ff8c296b6f8a60908
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Hedström, HelenaBixo, MarieNyberg, SigridZingmark, ElisabethBäckström, Torbjörn
By organisation
Obstetrics and Gynaecology
In the same journal
Psychopharmacology
Obstetrics, Gynecology and Reproductive Medicine

Search outside of DiVA

GoogleGoogle Scholar
Total: 389 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 128 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