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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Postoperativ smärta efter gynekologisk kirurgi

Tebini, Chaima, Petersson, Sara January 2009 (has links)
Syftet med denna studie var att undersöka patientens upplevelse av smärta efter gynekologisk operation. Studien avsåg även att undersöka patientens inställning till alternativa smärtlindringsmetoder. Metoden var en intervjustudie med en semistrukturerad intervjuguide. Sex patienter från en postoperativ gynekologisk avdelning intervjuades. Materialet analyserades med en innehållsanalytisk ansats och resulterade i fem huvudkategorier: Fysisk smärta och oro, tidigare erfarenheters påverkan, betydelsen av preoperativa förberedelser, sjukhusvistelsens påverkan och inställningen till alternativa smärtlindringsmetoder. Resultatet visade att den postoperativa smärtupplevelsen är individuell och beror på många olika faktorer. Smärta och oro postoperativt är omöjliga att urskilja från varandra och det kausala sambandet är inte alltid tydligt. Andra fynd som upptäcktes i resultatet är att sjuksköterskan sällan tar hänsyn till oro och andra psykiska faktorer vid smärtbedömningen. Patienternas inställning till alternativa smärtlindringsmetoder var positiv, då det ansågs ge avslappnande och därmed smärtlindrande effekt. För att förbättra den postoperativa smärtupplevelsen kan det ses som önskvärt om sjuksköterskan i omvårdnadsarbetet tog större hänsyn till psykiska faktorer som påverkar den postoperativa smärtan. Även användandet av alternativa smärtlindringsmetoder som komplement till den farmakologiska smärtbehandlingen hade förmodligen kunnat påverka smärtupplevelsen positivt. / The purpose of this study was to examine the patient’s experience of pain after gynecological surgery. The study was also examining the patient’s attitude towards alternative pain relief methods. The method was an interview study with a semi-structured interview guide. Six patients from a postoperative gynecological department were interviewed. The material was analyzed with a content analytical approach and resulted in five main categories: physical pain and anxiety, the impact of past experiences, the importance of pre-operational preparations, the effect of hospitalization and attitudes towards alternative pain relief methods. The results showed that the postoperative pain experience is individual and depends on many factors. Pain and anxiety postoperatively is impossible to distinguish from each other and the causal relationship is not always clear. Other findings are that the nurse, in pain assessment, seldom takes anxiety and other psychological factors into account. The patients' attitudes towards alternative methods of pain relief were positive, as it was considered to provide relaxing and there fore pain relieving effect. In order to improve the postoperative pain experience, it would be desirable if the nurse in the nursing work had in mind the psychological factors that influence the postoperative pain. The use of alternative pain relief methods as a supplement to the pharmacological pain treatment could possibly also affect the experience of pain positively.
52

Kvinnors upplevelser av att genomgå en hysterektomi : En kvalitativ litteraurstudie / Women's experiences of undergoing a hysterectomy : A qualitative literature review

Karlsson, Hanna January 2023 (has links)
Bakgrund: Hysterektomi innebär att kvinnans livmoder opereras bort och är en av de vanligaste gynekologiska operationerna. Indikationer för ingreppet är vanligtvis benigna blödningsrubbningar, myom, endometrios, framfall och maligna gynekologiska tillstånd. Dessa tillstånd orsakar ett stort lidande för kvinnorna och sjuksköterskan behöver beakta både fysiska och psykiska aspekter inom omvårdnad för att kunna öka kvinnornas välbefinnande och livskvalitet. Syfte: Att beskriva kvinnors upplevelser av att genomgå en hysterektomi. Metod: Kvalitativ litteraturöversikt utifrån tio vetenskapliga artiklar. Databaserna som användes var CINAHL, Medline och Pubmed. En tematisk analys gjordes i fyra steg. Resultat: Fem teman framkom i resultatet; begränsad av en förändrad kropp, behov av stöd, en välfungerande vård, omvårdnad utan personcentrering samt påverkad livskvalitet efter operationen. Konklusion: Kvinnor upplevde innan sin hysterektomi en förlust av sin egen kropp då den inte längre fungerade som tidigare. Detta ledde till en förlust av deras identitet och påverkade deras vardagliga liv. Kvinnorna var i stort behov av att få begriplig information och stöd av både vårdpersonal och sin omgivning. Den specialiserade vården sågs som välfungerande men kvinnorna saknade personcentrering i vården. / Background: A hysterectomy means that the woman’s uterus is surgically removed and is one of the most common gynecological surgeries. Indications for the procedure are usually benign bleeding disorders, fibroids, endometriosis, prolapse and malignant gynecological conditions. These conditions cause a great suffering for the women and the nurse need to consider both physical and psychological aspects in nursing to be able to increase the women's well-being and quality of life. Aim: To describe women's experiences of undergoing a hysterectomy. Method: Qualitative literature review based on ten scientific articles. The databases used were CINAHL, Medline and Pubmed. A thematic analysis was done in four steps. Findings: Five themes emerged in the results; limited by a changed body, need for support, a well-functioning care, care without person-centeredness and an affected quality of life after the operation. Conclusion: Before their hysterectomy, women experienced a loss of their own body as it no longer functioned as before. This led to a loss of their identity and affected their everyday lives. The women needed comprehensible information and support from both healthcare professionals and their surroundings. Specialized care was seen as well-functioning, but the women lacked person-centered care.
53

Behavioral effects of female sex steroid hormones : models of PMS and PMDD in Wistar rats

Löfgren, Magnus January 2009 (has links)
Background Animal models can be used to mimic human conditions of psychopathology, and also as pre-clinical models to evaluate candidate drugs. With hormonal treatment it is possible to produce behavior in the rat which corresponds to the mental symptoms of pre-menstrual syndrome (PMS), and pre-menstrual dysphoric disorder (PMDD). PMS affects 25-30 % of all women in fertile age and 3-8% are diagnosed with the more severe condition PMDD. The cardinal mental symptoms are; irritability, mood-swings, depression, anxiety, fatigue, insomnia, difficulties with concentration and memory and learning difficulties. The symptoms of PMS/PMDD occur in the luteal phase in conjunction with increasing concentrations of progesterone (P4) and P4-metabolites. In anovulatory cycles the symptoms are absent. The hormones which produce the monthly reoccurring negative symptoms on mood are foremost the neuroactive metabolites; allopregnanolone (ALLO) and tetrahydro-deoxycorticosterone (THDOC). ALLO is produced by the corpus luteum, but can also be synthesized in the brain, both ALLO and THDOC can also be released from the adrenal cortex during stress. These steroids are active on the inhibitory GABA neurotransmitter system through the GABAA receptor, and the effects are similar to that of alcohol and benzodiazepines. These steroids have strong sedative and hypnotic effects. A paradox is that some individuals seem to react with negative mood on sex steroids while all fertile women have the cyclical steroid changes during the menstrual cycle. Some individuals are more sensitive to neuroactive steroids with influences of personality, heritability and stress factors. Aims The thesis aims were to develop pre-clinical animal models of PMS/PMDD and to investigate induction of ALLO tolerance, individual sensitivity to neurosteroids and the interactions between chronic social stress and neurosteroids. Methods In these studies male and female Wistar rats were used to test steroid hormone effects on learning and memory and behaviors analogous to negative mood symptoms. This was accomplished through hormonal treatment and a subsequent withdrawal period from P4 (P4) + estradiol (E2) (PEWD), or ALLO. To assess tolerance, memory and learning in the Morris water maze (MWM) was studied. Anxiety-like behaviors were tested with the elevated plus maze (EPM), open field test (OFT), and the intruder test (IT). The EPM or OFT was used to classify the rats as high or low responders on risk-taking and explorative behavior (HR/LR). For social ranking order assessment the tube test (TT) and food competition test (FCT) were used. Chronic social stress was accomplished through co-habituation with two older rats (chronic subordination stress). In female rats the estrous cycle followed using staining of vaginal smears. Concentration of corticosterone (CORT) was measured by radio-immuno-assay (RIA). Results In the MWM ALLO pre-treatment produced tolerance to the acute negative ALLO effects. Both male and female rats showed behavioral correlations between the EPM and OFT tests, and correlations were also seen in CORT levels. Individuals with the stable trait of high risk-taking and explorative behavior (HR) were more sensitive to PEWD induction of anxiety-like behavior. These animals also showed decreased CORT levels during withdrawal. Chronic subordination stress enhanced the response to PEWD on measures of locomotor activity and social anxiety-like behavior. Conclusions It is possible to induce tolerance to the negative ALLO effects on learning and memory. The animal models of anxiety-like behavior show an individual PEWD response profile where HR rats are more sensitive. Exposure to chronic social stress enhanced the PEWD response. Hence there are both inherent and environmental factors behind the behavioral response to steroid hormones in rats. / Stress- och könshormoners verkningar på centrala nervsystemet
54

Maktstrukturer i gynekologin : Undersökning och kommentar på reproduktion av normer från 1800-talet i dagens patientupplevelse

Wilckens, Lina January 2017 (has links)
Stolar förhåller sig på ett mycket intimt sätt till våra kroppar och de kan även fungera som markörer i ett socialt maktspektrum. Gynekologstolen utvecklades under 1800-talet, den moderna medicinens glansdagar. Det var även en tid där kvinnor började begära större sociala och politiska rättigheter och det uppkom ett stort behov att biologiskt legitimera kvinnans underordning under mannen. Sedan dess har gynstolens strukturella utformning knappt förändrats. Den är en central symbol för den gynekologiska undersökningen och som jag kunde analysera i workshops och intervjuer kan den för patienter förknippas med känslor som utsatthet eller att ge upp bestämmelserätten över den egna kroppen. För vissa kvinnor är dessa känslor så starka att de skjuter upp kommande undersökningar eller undviker de helt. Som följd av det kan allvarliga sjukdomar förbli oupptäckta. I mitt kandidatarbete har jag undersökt patienters upplevelse av gynekologiska undersökningar idag och kopplat de till historiska erfarenheter. Huvudfokus av mitt arbete har som fysisk beröringspunkt varit gynekologstolen. Jag har vidare arbetat med formgivningen av en lounge chair som är lämpad för gynekologiska undersökningar. I framtagningen av stolen har jag valt att förhålla mig till design av sjukvårdsprodukter på ett icke-traditionellt sätt genom att lägga huvudfokus på patientupplevelsen. Genom detta har jag försökt att exemplifiera hur detta tillvägagångssätt i produktframtagning för vården kan leda till mer hållbara patientupplevelser. Mitt fokusområde har varit att förskjuta historiska maktförhållanden i gynekologin och att utveckla en stol för gynekologisk undersökning gemensamt med de som traditionellt inte har fått vara delaktiga i framtagningen av objekt som användes på deras kroppar: kvinnor. / <p>The full thesis contains copyrighted material which has been removed in the published version.</p>
55

Förlossningsrädsla : En begreppsanalys ur barnmorskans perspektiv / Fear of childbirth – a concept analysis from a midwife perspective

Birath, Camilla, Edman, Sofia January 2018 (has links)
Bakgrund: Förlossningsrädsla drabbar ungefär en femtedel av alla gravida kvinnor och barnmorskor möter dessa i sitt arbete. Syfte: Syftet var att analysera begreppet förlossningsrädsla ur ett barnmorskeperspektiv. Metod: En begreppsanalys med en hybridmodell. Först en teoretisk fas med litteratursökning, därefter en fältstudiefas där fem barnmorskor intervjuades följt av en sammanfattandes syntes med resultatet från den teoretiska fasen och fältstudiefasen. Resultat: Förlossningsrädsla är något som kan drabba kvinnor innan, under eller efter graviditet och förlossning. Förlossningsrädsla kan vara primär eller sekundär. Vid primär förlossningsrädsla kan kvinnan sakna tilltro till sin förmåga att föda barn och vid sekundär förlossningsrädsla har kvinnan haft en tidigare traumatisk förlossningsupplevelse. Barnmorskorna beskrev förlossningsrädsla som ett komplext begrepp. Kvinnorna använde oftast inte ordet förlossningsrädsla utan barnmorskorna tolkade vad de märkte eller såg hos kvinnan som yttringar av förlossningsrädsla. Slutsats: Barnmorskor använder begreppet på olika sätt och efterlyser en tydligare definition och arbetssätt kring förlossningsrädsla. Förlossningsrädsla innebär ett stort lidande för den gravida kvinnan och därför anser författarna till detta examensarbete att det förebyggande arbetet är viktigt och att barnmorskan har en central och betydelsefull roll. Kliniks tillämpbarhet: Barnmorskor kan använda sig av studien för att utveckla sin kunskap kring förlossningsrädsla samt se hur andra barnmorskor ser på begreppet förlossningsrädsla. / Background: Fear of childbirth affects about one-fifth of all pregnant women and midwives face these in their work. Aim: The aim was to analys the concept fear of childbirth from a midwife perspective. Methods: A concept analysis with a hybrid model. First a theoretical phase with a search for literature, thereafter a fieldwork phase where five midwifes where interviewed followed by a final analytic phase. Results: Fear of childbirth is something that can affect women before, during or after pregnancy and childbirth. Fear of childbirth for primiparous women can be a lack of confidence in her ability to give birth, and for multiparous women have had a previous traumatic birth experience. The midwives described that fear of childbirth was a complex concept. Women did not usually use the word fear of childbirth, but the midwives interpreted what they noticed or saw in the woman as manifestations of fear of childbirth. Conclusion: Midwives use the concept in different ways and call for a clearer definition and way of working with fear of childbirth. The fear of childbirth is a great suffering for the pregnant woman and therefore the authors of this thesis consider that preventive work is important and that the midwife has a central and important role. Clinical Applicability: Midwives can use this study to develop their knowledge of fear of childbirth and see how other midwives view on the concept fear of childbirth.
56

Kvinnors upplevelser av barnmorskans stöd vid förlossningsrädsla : En kvalitativ metasyntes / Women´s experiences of midwifes support regarding fear of childbirth : A qualitative meta-synthesis

Gustafsson, Lisa, Östhaug, Anna Lisa January 2018 (has links)
Bakgrund: Förlossningsrädsla kan vara påfrestande för kvinnor, förekommer i varierande allvarlighetsgrad och kan leda till negativ förlossningsupplevelse. Förekomsten av förlossningsrädsla varierar mellan olika länder vilket till viss del kan förklaras av olika mätmetoder. Barnmorskan är en betydelsefull person för kvinnor med förlossningsrädsla. Syfte: Syftet med denna studie var att undersöka kvinnors upplevelser och erfarenheter av barnmorskans stöd vid förlossningsrädsla. Metod: Kvalitativ metasyntes med meta-etnografisk analysmetod, där artiklar söktes i databaserna PubMed, CINAHL, Google Scholar, Scopus, Web of Science och PsycINFO. Efter kvalitetsgranskning kom 15 artiklar att analyseras. Resultat: Tre kategorier med tillhörande mönster identifierades; En närvarande barnmorska och En kompetent barnmorska där kvinnornas upplevelser av barnmorskans stöd bidrog till att minska förlossningsrädslan. Kategorin En distanserad barnmorska med tillhörande mönster visar upplevelser som istället ökade förlossningsrädslan. Slutsats: Resultatet påvisar betydelsen av att kvinnor upplever att barnmorskan är närvarande och kompetent för att kvinnan ska känna sig trygg och våga lita på att hon kan föda. Kontinuerligt stöd vid förlossning och fortbildning till personalen som möter förlossningsrädda kvinnor behövs. Caseload kan vara en modell som ytterligare behöver implementeras i barnmorskans arbete. / Background: Fear of childbirth can be stressful for women, occurs in varying degrees of severity and can lead to negative birth experience. The incidence of fear of childbirth varies between different countries, which to some extent can be explained by different measurement methods. The midwife is a person of significance for women with fear of childbirth. Objective: The purpose of this study was to investigate women's experiences of a midwife's support during fear of childbirth. Method: Qualitative meta synthesis using meta-ethnographic analysis method, where articles were searched in the databases PubMed, CINAHL, Google Scholar, Scopus, Web of Science and PsycINFO. After a quality review, 15 articles were analyzed. Result: Three categories with correlating patterns were identified; A present midwife and a competent midwife where the women's experience of the midwives support contributed to alleviate childbirth fear; Category a distant midwife with correlating patterns displays experiences that tended to increase childbirth fear. Conclusion: The results display the importance of the women's experience of a present and competent midwife for the women to feel safe and dare trust that she can give birth. A continuous support at childbirth and education for the staff that encounters women with fear of childbirth is needed. Caseload could be one model that needs to be implemented in the midwives work.
57

Livskvalitet hos mammor till för tidigt födda barn under det första året efter förlossningen : En longitudinell kohortstudie / Quality of life among mothers of preterm infants during the first year after birth : A longitudinal cohort study

Rahm, Elin, Heister-Rosvold, Linnea January 2018 (has links)
Bakgrund För tidig födsel innebär ökade risker för barnets liv och hälsa. Att få ett mycket för tidigt fött barn och därmed behöva vårdas på neonatalavdelning kan vara traumatiskt, omvälvande och stressande för mammor och kan ha stor betydelse för deras livskvalitet. Syfte Att beskriva mammor till för tidigt födda barns livskvalitet och påverkande faktorer upp till 12 månader efter förlossningen. Metod Studien hade en kvantitativ design och var en longitudinell kohortstudie där mammor (n=493) till barn som vårdats på sex olika neonatalavdelningar i Sverige fick svara på enkäter om livskvalitet (SF-36) vid fyra olika tillfällen under det första året efter förlossningen. Data har analyserats för att se vilka faktorer som kan ha haft betydelse för mammans livskvalitet samt om det fanns några skillnader över tid. Resultat Lägst livskvalitet skattades vid utskrivning från neonatalavdelning med en signifikant och successiv förbättring de kommande 12 månaderna (p &lt;0,01). Inom grupperna med olika faktorer fanns vissa signifikanta skillnader i livskvalitet med liten eller medelhög effektstorlek i några dimensioner av livskvalitet. Slutsats Mammorna skattade lägre livskvalitet vid utskrivning än senare under det första året och det fanns skillnader i livskvalitet mellan olika grupper av mammor. Detta är viktig kunskap för hälso- och sjukvårdspersonal i mötet med mammor till för tidigt födda barn. Klinisk tillämpbarhet Resultatet kan hjälpa barnmorskor och även barnsjuksköterskor och distriktsjuksköterskor att få en bättre förståelse för mammor till för tidigt födda barn och därmed kunna förebygga ohälsa och stötta mammorna för att främja en god anknytning till barnet. / Background Premature birth involves an increased risk for the child's life and health. Having a preterm infant and thus needing care at a neonatal unit may be traumatic and stressful for mothers and also have a great impact on their quality of life. Aim To describe the quality of life among mothers of preterm infants and influencing factors up to 12 months after birth. Method The study had a quantitative design and was a longitudinal cohort study. Mothers (n = 493) of preterm infants who were cared for at six neonatal units in Sweden answered questionnaires about quality of life (SF-36) on four different occasions during the first year after birth. Data has been analyzed to see which factors that may have had an impact on the mother's quality of life and whether there were any differences over time. Results The lowest quality of life was estimated at discharge from the neonatal unit with a significant and gradual improvement in the first year after delivery (p&lt;0,01). Within the different groups of mothers, there were significant differences in quality of life with a small or medium effect size in some dimensions of quality of life. Conclusion The mothers in this study rated their quality of life lowest at the time for discharge from the neonatal unit, and there were differences in quality of life between different groups of mothers. This is important knowledge for healthcare professionals. Clinical application The result of this study may help midwives and other healthcare professionals to gain a better understanding of mothers of preterm infants and their situation and thereby prevent mental illness and support the mothers to promote secure attachment with their children.
58

Miscarriage : Women’s Experience and its Cumulative Incidence

Adolfsson, Ann-Sofie January 2006 (has links)
Many women experience miscarriage every year. Every fourth woman who has given birth reports that she has previous experience of miscarriage. In a study of all women in the Swedish Medical Birth Register 1983-2003, we found that the number of cases of self reported miscarriage had increased in Sweden during this 21 year period. This increase can be explained by the introduction of sensitive pregnancy tests around 1990, as well as an increase in the mean age of the mothers, by approximately 3 years, during the observation period. The risk of miscarriage is 13% with the first child. With subsequent pregnancies, the risk of miscarriage is 8%, 6% and 4% with the second, third and fourth child, respectively. Thirteen of these women who had suffered a recent miscarriage were interviewed four months later, and their feelings of guilt and emptiness were explored. Their experience was that they wanted their questions to be answered, and that they wanted others to treat them as the mothers to be that they felt themselves to be. They also experienced the need for time to grieve their loss. Measurement of grief by means of the Perinatal Grief Scale (PGS) is used in research but has also been proposed for clinical use. We have translated this psychological instrument to Swedish, back-translated and tested it in a small pilot study. In a randomized controlled study, women with early miscarriage were allocated, either to a structured visit (study group) or a regular visit (control group) to a midwife. The structured visit was conducted according to the Swanson caring theory. We could conclude that the structured visit had no significant effect on grief compared to the regular visit, as measured using the PGS. However, women with the sub-diagnosis missed abortion have significantly more grief four months after early miscarriage, regardless of visit type. We also performed a content analysis of the tape-recorded structured follow-up visit. The code-key used was Bonanno and Kaltman’s general grief categorization. Women’s expression of grief after miscarriage was found to be very similar to the grief experienced following the death of a relative. Furthermore, the grief was found to be independent of number of children, women’s age, or earlier experience of miscarriage. Conclusions: Every fourth woman who gives birth reports that she has also experienced early miscarriage. The experience of these women is that they have suffered a substantial loss and their reaction is grief similar to that experienced following the death of a relative. / On the day of the public defence of the doctoral thesis the status of article III was In Press and article IV was In Press.
59

Birth-characteristics, hospitalisations, and childbearing : Epidemiological studies based on Swedish register data

Ekholm Selling, Katarina January 2007 (has links)
In the past decades there has been an improvement in the medical treatment of children born preterm or with reduced foetal growth. This has resulted in a much higher survival rate of these children, but also in a higher number of surviving children with chronic conditions. These changes have, in turn, increased interest in investigating the connection between birth-characteristics and outcomes in later life. The overall aim of the present thesis was to study the relations between birth-characteristics, subsequent hospitalisations, and childbearing by means of data available in Swedish population-based registries. The study population in this thesis consisted of women (and men in Paper III) born in 1973-75 according to the Medical Birth Register and the Total Population Register. Information available in other registries, such as the Hospital Discharge Register, was obtained by individual record linkage. In Paper I, 148,281 women, alive and living in Sweden at 13 years of age, were included. Of the women, 4.1% were born preterm and 5.4% were born small for gestational age, and approximately 30% of all women had given birth between 13 and 27 years of age. We found that reduced foetal growth and possibly preterm birth were related to the likelihood of giving birth during the study period. The intergenerational effects of preterm birth and reduced foetal growth were investigated in Paper II and the study population consisted of 38,720 mother-offspring pairs. An intergenerational effect of reduced foetal growth was found, and reduced foetal growth in the mother also increased the risk for preterm birth in the child. Paper III was concerned with 304,275 men and women living in Sweden at 13 years of age. Of these men and women, 30% were hospitalised during adolescence and early adulthood (i.e. between 12 and 23 years of age). We found that men and women born small for gestational age or preterm were more likely to be hospitalised, and that those born small for gestational age seemed to be more at risk compared to those born preterm. Finally, in Paper IV, the relation between hospitalisations during adolescence and the likelihood of giving birth was studied in 142,998 women living in Sweden at 20 years of age. We found that a majority of the causes of hospitalisation during adolescence were positively connected to the likelihood of giving birth between 20 and 27 years of age. The relations presented in Papers I-IV were evident although socio-economic characteristics were adjusted for.
60

Progesterone metabolites : learning, tolerance, antagonism &amp; metabolism

Öfverman, Charlotte January 2009 (has links)
Progesterone metabolites as allopregnanolone, isoallopregnanolone and tetrahydrodeoxy-corticosterone (THDOC) are increased in the luteal phase of the menstrual cycle, throughout pregnancy and during stress. Allopregnanolone and THDOC are neurosteroids with 3α-hydroxy, 5α-configurations and positive modulating effect on the GABAA receptor. They have similar properties and effect, and share the same binding sites on the GABAA receptor. Isoallopregnanolone has a 3β-hydroxy, 5α-configuration and a diverse effect as a proposed antagonist to both allopregnanolone and THDOC. Neurosteroids are thought to exert their effect predominantly at extrasynaptic GABAA receptors, containing for example α4- or α5-subunits. Such receptors are involved in the tonic response. Different subunits have diverse distribution pattern in the brain and are involved in different functions. The α5-subunit, mainly expressed in the hippocampus, is involved in learning, while α4 is more widespread and involved in e.g. anxiety and anaesthesia. The aim of the present thesis was to contribute to the knowledge about selected progesterone metabolites and their effects on learning and tolerance development, as well as their metabolism. Also basic characteristics between different α-subunits of the GABAA receptor were evaluated. The thesis shows that the effect of bicuculline and pentobarbital is not dependent on the α-subunit isoform of the GABAA receptor expressed in oocytes. Acute tolerance developed after allopregnanolone-induced anaesthesia with a decrease at both mRNA and protein levels of the GABAA receptor α4-subunit in the thalamus VPM nucleus. A negative correlation between the α4 mRNA and the increased dose of allopregnanolone needed to maintain the anaesthesia level was also shown. In addition, allopregnanolone induces a learning impairment in the Morris water maze test, when high concentrations of allopregnanolone are present in the brain. This impairment is not possible to reverse by isoallopregnanolone. In α5β3γ2L-transfected HEK-293 cells THDOC induces a baseline shift of its own and also potentiate the GABA-current. Neither of those THDOC effects can be inhibited by isoallopregnanolone. Instead isoallopregnanolone shows an agonistic effect on the THDOC-potentiation of the GABA-response. The main allopregnanolone metabolites identified, 5α-DHP and isoallopregnanolone, as well as allopregnanolone itself are mainly localized to the brain after an i.v. injection. After an isoallopregnanolone injection there is a more even distribution of the given steroid and the metabolites between plasma and brain. There is an epimerisation between isoallopregnanolone and allopregnanolone and vice versa. In conclusion, the present thesis shows that the α4-subunit in the thalamus VPM nucleus is likely to be involved in the acute tolerance development against allopregnanolone and that allopregnanolone-induced learning impairment is likely to be hippocampus dependent. The lack of antagonistic effect of isoallopregnanolone on the THDOC-induced α5β3γ2L-GABAA response, together with epimerisation of isoallopregnanolone to allopregnanolone, could explain why isoallopregnanolone does not work as an antagonist to the allopregnanolone-induced learning impairment in a hippocampus dependent learning task.

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