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Johansson, Inga-Maj
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Publications (10 of 38) Show all publications
Holmberg, E., Johansson, M., Bäckström, T., Löfgren, M. & Haage, D. (2015). Repeated allopregnanolone exposure induces weight gain in schedule fed rats on high fat diet. Physiology and Behavior, 140, 1-7
Open this publication in new window or tab >>Repeated allopregnanolone exposure induces weight gain in schedule fed rats on high fat diet
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2015 (English)In: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 140, p. 1-7Article in journal (Refereed) Published
Abstract [en]

Ingestion of energy rich high fat diets is one of the determining factors associated with the obesity epidemic. Therefore, much can be learned from studies of obesity-related substances given to animals fed a high fat diet.The progesterone metabolite allopregnanolone is a potent positive modulator of the gamma-aminobutyric acid(GABA)A-receptor, and both allopregnanolone and GABA have been implicated in evoking hyperphagia. In this study, food intake and body weight gain were investigated during repeated allopregnanolone exposure. Male Wistar rats were studied when fed chow ad libitum, with chow access for 4h per day or with 45% high fat pellets for 4 h per day. Rats on the high fat diet were separated into obesity prone and obesity resistant individuals.Subcutaneous injections of allopregnanolone were given once daily overfive consecutive days. Repeated exposure to allopregnanolone lead to increased weight gain, significantly so in schedule fed rats on a high fat diet. The increased weight gain was correlated to an increased energy intake. Both obesity resistant and obesityprone rats responded to allopregnanolone with increased weight gain. Obesity resistant rats treated with allopregnanolone increased their energy intake and ate as much as vehicle treated obesity prone rats. Their weight gain was also increased to the level of obesity prone rats injected with just the vehicle carrier oil. Thus, it appears that allopregnanolone may be one of the endogenous factors involved in weight gain, especiallywhen the diet is rich in fat.

Place, publisher, year, edition, pages
Elsevier, 2015
Keyword
Allopregnanolone Neurosteroid Weight gain Food intake Scheduled feeding High fat diet
National Category
Neurosciences Physiology Obstetrics, Gynecology and Reproductive Medicine
Identifiers
urn:nbn:se:umu:diva-101793 (URN)10.1016/j.physbeh.2014.12.012 (DOI)000349588400001 ()
Available from: 2015-04-13 Created: 2015-04-13 Last updated: 2018-01-11Bibliographically approved
Bäckström, T., Bixo, M., Johansson, M., Nyberg, S., Ossewaarde, L., Ragagnin, G., . . . van Wingen, G. (2014). Allopregnanolone and mood disorders. Progress in Neurobiology, 113, 88-94
Open this publication in new window or tab >>Allopregnanolone and mood disorders
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2014 (English)In: Progress in Neurobiology, ISSN 0301-0082, E-ISSN 1873-5118, Vol. 113, p. 88-94Article in journal (Refereed) Published
Abstract [en]

Certain women experience negative mood symptoms during the menstrual cycle and progesterone addition in estrogen treatments. In women with PMDD increased negative mood symptoms related to allopregnanolone increase during the luteal phase of ovulatory menstrual cycles. In anovulatory cycles no symptom or sex steroid increase occurs. This is unexpected as positive modulators of the GABA-A receptor are generally increasing mood. This paradoxical effect has brought forward a hypothesis that the symptoms are provoked by allopregnanolone the GABA-A receptor system. GABA-A is the major inhibitory system in the brain. Positive modulators of the GABA-A receptor include the progesterone metabolites allopregnanolone and pregnanolone, benzodiazepines, barbiturates, and alcohol. GABA-A receptor modulators are known, in low concentrations to induce adverse, anxiogenic effects whereas in higher concentrations show beneficial, calming properties. Positive GABA-A receptor modulators induce strong paradoxical effects e.g. negative mood in 3-8% of those exposed, while up to 25% have moderate symptoms thus similar as the prevalence of PMDD, 3-8% among women in fertile ages, and up to 25% have moderate symptoms of premenstrual syndrome (PMS). The mechanism behind paradoxical reaction might be similar among them who react on positive GABA-A receptor modulators and in women with PMDD. In women the severity of these mood symptoms are related to the allopregnanolone serum concentrations in an inverted U-shaped curve. Negative mood symptoms occur when the serum concentration of allopregnanolone is similar to endogenous luteal phase levels, while low and high concentrations have less effect on mood. Low to moderate progesterone/allopregnanolone concentrations in women increases the activity in the amygdala (measured with fMRI) similar to the changes seen during anxiety reactions. Higher concentrations give decreased amygdala activity similar as seen during benzodiazepine treatment with calming anxiolytic effects. Patients with PMDD show decreased sensitivity in GABA-A receptor sensitivity to diazepam and pregnanolone while increased sensitivity to allopregnanolone. This agrees with findings in animals showing a relation between changes in alpha4 and delta subunits of the GABA-A receptor and anxiogenic effects of allopregnanolone. Conclusion: These findings suggest that negative mood symptoms in women with PMDD are caused by the paradoxical effect of allopregnanolone mediated via the GABA-A receptor.

(c) 2013 Elsevier Ltd. All rights reserved.

National Category
Obstetrics, Gynecology and Reproductive Medicine
Identifiers
urn:nbn:se:umu:diva-87179 (URN)10.1016/j.pneurobio.2013.07.005 (DOI)000331508100007 ()
Available from: 2014-03-31 Created: 2014-03-24 Last updated: 2017-12-05Bibliographically approved
Holmberg, E., Johansson, M., Bäckström, T. & Haage, D. (2014). Allopregnanolone preferentially induces energy-rich food intake in male Wistar rats. Physiological Reports, 2(12), e12190
Open this publication in new window or tab >>Allopregnanolone preferentially induces energy-rich food intake in male Wistar rats
2014 (English)In: Physiological Reports, E-ISSN 2051-817X, Vol. 2, no 12, p. e12190-Article in journal (Refereed) Published
Abstract [en]

Obesity is an increasing problem and identification of the driving forces for overeating of energy-rich food is important. Previous studies show that the stress and sex steroid allopregnanolone has a hyperphagic effect on both bland food and palatable food. If allopregnanolone induces a preference for more palatable or for more energy-rich food is not known. The aim of this study  was to elucidate the influence of allopregnanolone on food preference. Male Wistar rats were subjected to two different food preference tests: a choice between standard chow and cookies (which have a higher energy content and also are more palatable than chow), and a choice between a low caloric sucrose solution and standard chow (which has a higher energy content and is less palatable than sucrose). Food intake was measured for 1 h after acute subcutaneous injections of allopregnanolone. In the choice between cookies and chow allopregnanolone significantly increased only the intake of cookies.When the standard chow was the item present with the highest caloric load, the chow intake was increased and allopregnanolone had no effect on intake of the 10% sucrose solution. The increased energy intakes induced by the high allopregnanolone dose compared to vehicle were very similar in the two tests,120% increase for cookies and 150% increase for chow. It appears that in allopregnanolone-induced hyperphagia, rats choose the food with the highest energy content regardless of its palatability.

Place, publisher, year, edition, pages
Wiley Periodicals Inc., 2014
Keyword
Allopregnanolone, energy need, food intake, neurosteroids GABA
National Category
Neurosciences Physiology
Identifiers
urn:nbn:se:umu:diva-101791 (URN)10.14814/12190 (DOI)
Available from: 2015-04-13 Created: 2015-04-13 Last updated: 2018-01-11Bibliographically approved
Holmberg, E., Bäckström, T., Johansson, M., Löfgren, M. & Haage, D. (2013). Allopregnanolone induces a diurnally dependent hyperphagic effect and alters feeding latency and duration in male Wistar rats. Acta Physiologica, 208(4), 400-409
Open this publication in new window or tab >>Allopregnanolone induces a diurnally dependent hyperphagic effect and alters feeding latency and duration in male Wistar rats
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2013 (English)In: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 208, no 4, p. 400-409Article in journal (Refereed) Published
Abstract [en]

Aim: Gamma-aminobutyric acid (GABA)-ergic transmission from the hypothalamus is essential for normal feeding regulation, and hyperphagia can be induced by local application of GABA(A)-receptor agonists to different feeding-associated brain areas. The food intake in rats varies diurnally and that may influence the effect of GABA(A)-receptor active compounds. The progesterone metabolite allopregnanolone is a highly potent endogenous positive modulator of the GABA(A) receptor. Therefore, it is easy to envisage that allopregnanolone would have a hyperphagic effect, but earlier reports in rat have given ambiguous results. However, a contributing factor for the discrepancy may be the time point of the diurnal cycle in which the experiments were performed. The aim of this study was to investigate the effect of allopregnanolone on intake of standard chow in male Wistar rats at different time points of the day.

Methods: Chow intake was measured after acute administration of allopregnanolone, and feeding behaviour was analysed to detect meal patterns.

Results: We found that allopregnanolone increased chow intake by up to four times in the dark part of the 24-h cycle. The rats ate significantly more, and the effect of allopregnanolone was more prominent in the active (dark) compared with the inactive (light) period. Allopregnanolone also reduced feeding latency and prolonged the meal duration compared with vehicle.

Conclusion: Allopregnanolone seems to act at several levels of feeding regulation, that is, to initiate feeding and to prolong the duration of a meal, thereby increasing the meal size, especially in the dark period of the 24-h cycle.

Place, publisher, year, edition, pages
John Wiley & Sons, 2013
Keyword
allopregnanolone, diurnal rhythm, food intake, Gamma-aminobutyric acid, hyperphagia, neurosteroids
National Category
Obstetrics, Gynecology and Reproductive Medicine
Identifiers
urn:nbn:se:umu:diva-79224 (URN)10.1111/apha.12100 (DOI)000321695000013 ()
Available from: 2013-09-16 Created: 2013-08-13 Last updated: 2017-12-06Bibliographically approved
Löfgren, M., Bengtsson, S. K., Johansson, M. & Bäckström, T. (2013). Allopregnanolone promotes success in food competition in subordinate male rats. Neuropsychobiology, 68(1), 15-23
Open this publication in new window or tab >>Allopregnanolone promotes success in food competition in subordinate male rats
2013 (English)In: Neuropsychobiology, ISSN 0302-282X, E-ISSN 1423-0224, Vol. 68, no 1, p. 15-23Article in journal (Refereed) Published
Abstract [en]

Background/Aims: Allopregnanolone or 3 alpha-hydroxy-5 alpha-pregnan-20-one (AlloP) is normally sedative and anxiolytic, but can under provoking circumstances paradoxically induce aggressive behavior. Therefore, it is of particular interest to determine if there is a relationship between an anxiolytic effect and aggressive behavior following AlloP administration.

Method: Male Wistar rats were housed in triads comprising of 1 young rat (35 days) and 2 older rats (55 days), with the intent of producing a social hierarchy. The triads were sampled for total serum testosterone and submitted to a social challenge in the form of a food competition test (FCT), where the rats competed for access to drinking sweetened milk. At baseline, the younger rats were identified as subordinates. To test for the behavioral effect of AlloP, the subordinate rats were given intravenous AlloP injections of 0.5 and 1 mg/kg. To assess the optimal AlloP effect, 6 intervals (5, 10, 15, 20, 30 and 40 min) between injection and the FCT were used. In separate studies, AlloP was also given by subcutaneous and intraperitoneal administration at 10 and 17 mg/kg.

Results: AlloP (1 mg/kg, i.v.) increased drinking time and aggressive behavior in subordinate rats, with a positive correlation between these behaviors. The subcutaneous injection (17 mg/kg) also increased drinking time in subordinate animals. Serum testosterone concentration was higher in dominant compared to subordinate rats, and correlated with drinking time and weight.

Conclusions: AlloP increased drinking time and aggressive behavior, and the correlation indicates a relationship between an anxiolytic effect and aggressive behavior. Copyright (c) 2013 S. Karger AG, Basel

Keyword
Allopregnanolone, Anxiety, Behavior, Aggression, Hierarchy, Triad, Subordinate
National Category
Obstetrics, Gynecology and Reproductive Medicine
Identifiers
urn:nbn:se:umu:diva-79290 (URN)10.1159/000350478 (DOI)000321482500002 ()
Available from: 2013-08-23 Created: 2013-08-13 Last updated: 2017-12-06Bibliographically approved
Bengtsson, S. K., Johansson, M., Bäckström, T., Nitsch, R. M. & Wang, M. (2013). Brief but Chronic Increase in Allopregnanolone Cause Accelerated AD Pathology Differently in Two Mouse Models. Current Alzheimer Research, 10(1), 38-47
Open this publication in new window or tab >>Brief but Chronic Increase in Allopregnanolone Cause Accelerated AD Pathology Differently in Two Mouse Models
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2013 (English)In: Current Alzheimer Research, ISSN 1567-2050, Vol. 10, no 1, p. 38-47Article in journal (Refereed) Published
Abstract [en]

Previously, we have shown that chronic treatment with allopregnanolone (ALLO) for three months impaired learning function in the Swe/PS1 mouse model. ALLO is a neurosteroid, produced in the CNS and a GABA(A) receptor agonist. ALLO modulates the general inhibitory system in the CNS by enhancing the effect of GABA. Chronic treatment with other GABA(A) receptor active compounds, such as benzodiazepines, ethanol and medroxy-progesterone acetate has been associated to cognitive decline and/or increased risk for dementia. In this study, we sufficed with a treatment period of one month for the Swe/PS1 mouse, and included another Alzheimer's disease mouse model; the Swe/Arc model. We found that one month of chronic treatment with elevated ALLO levels within physiological range impaired learning and memory function in the Swe/Arc female and male mice. Male Swe/PS1 mice also showed marginally impaired function, while the female mice did not. Furthermore, the chronic ALLO treatment caused increased levels of soluble A beta in the Swe/PS1 mouse model while the levels were unchanged in the Swe/Arc model. Therefore, both Swe/Arc and Swe/PS1 mice showed signs of accelerated disease progression. Still, further studies are required to determine the mechanisms behind the cognitive impairment and the increased A beta-levels caused by mildly elevated ALLO-levels.

Place, publisher, year, edition, pages
Bentham Science Publishers, 2013
Keyword
Allopregnanolone, Alzheimer's disease, beta-amyloid(1-42), beta-amyloid(1-40), cognition, physiological stress, transgenic
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-70364 (URN)10.2174/156720513804871363 (DOI)000317271800006 ()
Available from: 2013-05-16 Created: 2013-05-14 Last updated: 2015-11-11Bibliographically approved
Bengtsson, S., Johansson, M., Bäckström, T., Nitsch, R. & Wang, M. (2013). Brief but Chronic Increase in Allopregnanolone Cause Accelerated ADPathology Differently in Two Mouse Models. Current Alzheimer Research, 10(1), 38-47
Open this publication in new window or tab >>Brief but Chronic Increase in Allopregnanolone Cause Accelerated ADPathology Differently in Two Mouse Models
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2013 (English)In: Current Alzheimer Research, ISSN 1567-2050, Vol. 10, no 1, p. 38-47Article in journal (Refereed) Published
Abstract [en]

Abstract: Previously, we have shown that chronic treatment with allopregnanolone (ALLO) for three months impaired learning function in the Swe/PS1 mouse model. ALLO is a neurosteroid, produced in the CNS and a GABAA receptor agonist. ALLO modulates the general inhibitory system in the CNS by enhancing the effect of GABA. Chronic treatment with other GABAA receptor active compounds, such as benzodiazepines, ethanol and medroxy-progesterone acetate has been associated to cognitive decline and/or increased risk for dementia. In this study, we sufficed with a treatment period of one month for the Swe/PS1 mouse, and included another Alzheimer’s disease mouse model; the Swe/Arc model. We found that one month of chronic treatment with elevated ALLO levels within physiological range impaired learning and memory function in the Swe/Arc female and male mice. Male Swe/PS1 mice also showed marginally impaired function, while the female mice did not. Furthermore, the chronic ALLO treatment caused increased levels of soluble Aβ in the Swe/PS1 mouse model while the levels were unchanged in the Swe/Arc model. Therefore, both Swe/Arc and Swe/PS1 mice showed signs of accelerated disease progression. Still, further studies are required to determine the mechanisms behind the cognitive impairment and the increased Aβ-levels caused by mildly elevated ALLO-levels. learning function in the Swe/PS1 mouse model. ALLO is a neurosteroid, produced in the CNS and a GABAA receptor agonist. ALLO modulates the general inhibitory system in the CNS by enhancing the effect of GABA. Chronic treatment with other GABAA receptor active compounds, such as benzodiazepines, ethanol and medroxy-progesterone acetate has been associated to cognitive decline and/or increased risk for dementia. In this study, we sufficed with a treatment period of one month for the Swe/PS1 mouse, and included another Alzheimer’s disease mouse model; the Swe/Arc model. We found that one month of chronic treatment with elevated ALLO levels within physiological range impaired learning and memory function in the Swe/Arc female and male mice. Male Swe/PS1 mice also showed marginally impaired function, while the female mice did not. Furthermore, the chronic ALLO treatment caused increased levels of soluble Ab in the Swe/PS1 mouse model while the levels were unchanged in the Swe/Arc model. Therefore, both Swe/Arc and Swe/PS1 mice showed signs of accelerated disease progression. Still, further studies are required to determine the mechanisms behind the cognitive impairment and the increased Aβ-levels caused by mildly elevated ALLO-levels.

Place, publisher, year, edition, pages
Bentham Science Publishers, 2013
Keyword
Alzheimer's disease, beta-amyloid proteins, allopregnanolone, chronic stress, transgenic mouse models, synaptophysin, amyloid plaques
National Category
Neurosciences
Research subject
Obstetrics and Gynaecology; Neurology; Medical Pharmacology; Geriatrics
Identifiers
urn:nbn:se:umu:diva-66571 (URN)
Funder
Swedish Research Council, 4x-11198
Available from: 2013-02-28 Created: 2013-02-25 Last updated: 2018-01-11Bibliographically approved
Bengtsson, S. K., Johansson, M., Bäckström, T. & Wang, M. (2012). Chronic Allopregnanolone Treatment Accelerates Alzheimer's Disease Development in A beta PP(Swe)PSEN1(Delta E9) Mice. Journal of Alzheimer's Disease, 31(1), 71-84
Open this publication in new window or tab >>Chronic Allopregnanolone Treatment Accelerates Alzheimer's Disease Development in A beta PP(Swe)PSEN1(Delta E9) Mice
2012 (English)In: Journal of Alzheimer's Disease, ISSN 1387-2877, E-ISSN 1875-8908, Vol. 31, no 1, p. 71-84Article in journal (Refereed) Published
Abstract [en]

The endogenous neurosteroid allopregnanolone alters neuronal excitability via modulation of the GABA(A) receptor and causes decreased neurotransmission. In Alzheimer's disease (AD), neurotransmission seems to alter the levels of toxic intracellular amyloid-beta (A beta) oligomers, which are implicated in AD pathogenesis and cause cognitive decline. Inhibition of synaptic activity has been shown to increase levels of intracellular A beta. Allopregnanolone at endogenous stress levels inhibits synaptic activity and could have similar effects. By using a transgenic A beta PP(Swe)PSEN1(Delta E9) mouse model for AD, we observed that chronic allopregnanolone treatment for three months with stress levels of allopregnanolone impaired learning in the Morris water maze. The learning impairment was seen one month after the end of treatment. Chronic allopregnanolone treatment also led to increased levels of soluble A beta in the brain, which could be a sign of advanced pathogenesis. Since the learning and memory of wild-type mice was not affected by the treatment, we propose that chronic allopregnanolone treatment accelerates the pathogenesis of AD. However, further studies are required in order to determine the underlying mechanism.

Keyword
Allopregnanolone, Alzheimer's disease, amyloid-beta, amyloid-beta(1-40), amyloid-beta(1-42), cognition, physiological stress
National Category
Neurosciences
Identifiers
urn:nbn:se:umu:diva-57556 (URN)10.3233/JAD-2012-120268 (DOI)000306122900009 ()
Available from: 2012-08-13 Created: 2012-08-06 Last updated: 2018-01-12Bibliographically approved
Löfgren, M., Johansson, M., Strömberg, J., Meyerson, B. & Bäckstrom, T. (2012). The influence of social subordinate housing on the withdrawal effects from progesterone and estradiol in male rats. General and Comparative Endocrinology, 177(1), 62-69
Open this publication in new window or tab >>The influence of social subordinate housing on the withdrawal effects from progesterone and estradiol in male rats
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2012 (English)In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 177, no 1, p. 62-69Article in journal (Refereed) Published
Abstract [en]

Chronic stress and its concomitant neurobiological consequences are, in all probability, provocateurs of mental disease in humans. To gain some insight into the provocative effects of stress on hormonally dependent conditions, we developed a rat model that combines social subordinate housing (SSH) with withdrawal from combined progesterone (P) and estradiol (E) treatment (PEVVD). At the start of the experiment, male Wistar rats were housed in triads consisting of one younger rat (35 days old) and two older rats (55 days old), with the intent of producing subordination stress in the younger animals. Triads containing three 35-day-old rats were used as age controls. Subordination stress was assessed with the elevated plus maze (EPM) and by corticosterone (CORT) analysis. Social rank within the triads was determined using a food competition test (FCT) and a tube test (TT). The younger rats (subordinate) and the dominant rats were assigned to 10 days of treatment with 5 mg/kg P combined with 10 mu g/kg E, or placebo (vehicle). Twenty-four hours after the last injection, the subordinate and dominant animals were tested in an open-field test (OFT) and a social challenge test (SCT). The SCT consisted of a 10-min exposure to three unfamiliar rats. SSH increased baseline CORT levels and reduced EPM open-arm time and post-EPM CORT levels compared to age-control rats. Only in the subordinate animals did PEWD increase locomotor activity and digging behavior, and reduce wrestling and pinning behavior. The behavioral results indicate an interaction between the effects of the lasting social subordinate stress and PEWD. (C) 2012 Elsevier Inc. All rights reserved.

Place, publisher, year, edition, pages
San Diego: Elsevier, 2012
Keyword
Social stress, Progesterone, Estradiol, Allopregnanolone, Elevated plus maze, Open field
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:umu:diva-56697 (URN)10.1016/j.ygcen.2012.02.011 (DOI)000304511500008 ()
Available from: 2012-06-26 Created: 2012-06-25 Last updated: 2017-12-07Bibliographically approved
Bäckström, T., Haage, D., Löfgren, M., Johansson, I. M., Strömberg, J., Nyberg, S., . . . Bengtsson, S. K. (2011). Paradoxical effects of GABA-A modulators may explain sex steroid induced negative mood symptoms in some persons. Neuroscience, 191(Special issue), 46-54
Open this publication in new window or tab >>Paradoxical effects of GABA-A modulators may explain sex steroid induced negative mood symptoms in some persons
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2011 (English)In: Neuroscience, ISSN 0306-4522, E-ISSN 1873-7544, Vol. 191, no Special issue, p. 46-54Article, review/survey (Refereed) Published
Abstract [en]

Some women have negative mood symptoms, caused by progestagens in hormonal contraceptives or sequential hormone therapy or by progesterone in the luteal phase of the menstrual cycle, which may be attributed to metabolites acting on the GABA-A receptor. The GABA system is the major inhibitory system in the adult CNS and most positive modulators of the GABA-A receptor (benzodiazepines, barbiturates, alcohol, GABA steroids), induce inhibitory (e.g. anesthetic, sedative, anticonvulsant, anxiolytic) effects. However, some individuals have adverse effects (seizures, increased pain, anxiety, irritability, aggression) upon exposure. Positive GABA-A receptor modulators induce strong paradoxical effects including negative mood in 3%-8% of those exposed, while up to 25% have moderate symptoms. The effect is biphasic: low concentrations induce an adverse anxiogenic effect while higher concentrations decrease this effect and show inhibitory, calming properties. The prevalence of premenstrual dysphoric disorder (PMDD) is also 3%-8% among women in fertile ages, and up to 25% have more moderate symptoms of premenstrual syndrome (PMS). Patients with PMDD have severe luteal phase-related symptoms and show changes in GABA-A receptor sensitivity and GABA concentrations. Findings suggest that negative mood symptoms in women with PMDD are caused by the paradoxical effect of allopregnanolone mediated via the GABA-A receptor, which may be explained by one or more of three hypotheses regarding the paradoxical effect of GABA steroids on behavior: (1) under certain conditions, such as puberty, the relative fraction of certain GABA-A receptor subtypes may be altered, and at those subtypes the GABA steroids may act as negative modulators in contrast to their usual role as positive modulators; (2) in certain brain areas of vulnerable women the transmembrane C1(-) gradient may be altered by factors such as estrogens that favor excitability; (3) inhibition of inhibitory neurons may promote disinhibition, and hence excitability. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain. (C) 2011 Published by Elsevier Ltd on behalf of IBRO.

Place, publisher, year, edition, pages
Oxford: , 2011
Keyword
premenstrual syndrome, GABA-A receptor, paradoxical, GABA-steroid, neurosteroid
National Category
Neurology Neurosciences
Identifiers
urn:nbn:se:umu:diva-49248 (URN)10.1016/j.neuroscience.2011.03.061 (DOI)000295749300006 ()
Available from: 2011-11-09 Created: 2011-11-04 Last updated: 2018-03-15Bibliographically approved
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