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Hermes M, Antonow-Schlorke I, Hollstein D, Kuehnel S, Rakers F, Frauendorf V, Dreiling M, Rupprecht S, Schubert H, Witte OW, Schwab M. Maternal psychosocial stress during early gestation impairs fetal structural brain development in sheep. Stress 2020; 23:233-242. [PMID: 31469022 DOI: 10.1080/10253890.2019.1652266] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Maternal stress, especially during early pregnancy, predisposes offspring to neuropsychiatric disorders. We hypothesized that maternal psychosocial stress (MPS) during pregnancy affects fetal structural neurodevelopment depending on the gestational age of exposure. Fetal sheep brains were harvested at 130 days gestation (dG, term 150 dG) from ewes frequently isolated from flock-mates during early gestation (first and second trimester; n = 10) or late gestation (third trimester; n = 10), or from control flock-mates (n = 8). Immunohistochemistry for formation of neuronal processes, myelination, synaptic density, cell proliferation and programed cell death was performed on brain tissue sections. Sections of the cortical gray matter, the hippocampal CA3 region and the superficial, subcortical and deep white matter were examined morphometrically. Stress effects depended on the brain region and time of exposure. Stress during early gestation but not during late gestation reduced the amount of neuronal processes in the cerebral cortex and hippocampus by 36.9 ± 10.1% (p < 0.05, mean ± SEM) and 36.9 ± 15.8% (p < 0.05), respectively, accompanied by a decrease in synaptic density in the cerebral cortex and hippocampus by 39.8 ± 23.1% (p < 0.05) and 32.9 ± 13.4% (p < 0.01). Myelination was decreased in white matter layers on average by 44.8 ± 11.7% (p < 0.05) accompanied by reduced (glial) cell proliferation in the deep white matter by 83.6 ± 12.4% (p < 0.05). In contrast, stress during the third trimester had no effect in any brain region. Chronic MPS during the first and second trimester induced prolonged effects on neuronal network and myelin formation which might contribute to disturbed neurobehavioral, cognitive and motor development in offspring of stressed mothers.Lay summaryMany women are exposed to stressful events during pregnancy. Maternal stress especially during early pregnancy predisposes for offspring's neuropsychiatric disorders. In our sheep study, we show that disturbance of fetal brain development is a potential mechanism and is worst during 1st and 2nd trimester.
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Affiliation(s)
- Markus Hermes
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | | | - Dorothea Hollstein
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Sarah Kuehnel
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Florian Rakers
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Vilmar Frauendorf
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Michelle Dreiling
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Sven Rupprecht
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
- Else Kröner-Forschungskolleg AntiAge, Bad Homburg, Germany
| | - Harald Schubert
- Institute of Lab Animal Sciences and Welfare, Jena University Hospital, Jena, Germany
| | - Otto W Witte
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Matthias Schwab
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
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Cardiovascular effects of prenatal stress-Are there implications for cerebrovascular, cognitive and mental health outcome? Neurosci Biobehav Rev 2019; 117:78-97. [PMID: 31708264 DOI: 10.1016/j.neubiorev.2018.05.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 01/17/2023]
Abstract
Prenatal stress programs offspring cognitive and mental health outcome. We reviewed whether prenatal stress also programs cardiovascular dysfunction which potentially modulates cerebrovascular, cognitive and mental health disorders. We focused on maternal stress and prenatal glucocorticoid (GC) exposure which have different programming effects. While maternal stress induced cortisol is mostly inactivated by the placenta, synthetic GCs freely cross the placenta and have different receptor-binding characteristics. Maternal stress, particularly anxiety, but not GC exposure, has adverse effects on maternal-fetal circulation throughout pregnancy, probably by co-activation of the maternal sympathetic nervous system, and by raising fetal catecholamines. Both effects may impair neurodevelopment. Experimental data also suggest that severe maternal stress and GC exposure during early and mid-gestation may increase the risk for cardiovascular disorders. Human data are scarce and especially lacking for older age. Programming mechanisms include aberrations in cardiac and kidney development, and functional changes in the renin-angiotensin-aldosterone-system, stress axis and peripheral and coronary vasculature. Adequate experimental or human studies examining the consequences for cerebrovascular, cognitive and mental disorders are unavailable.
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Anegroaie P, Frasch MG, Rupprecht S, Antonow-Schlorke I, Müller T, Schubert H, Witte OW, Schwab M. Development of somatosensory-evoked potentials in foetal sheep: effects of betamethasone. Acta Physiol (Oxf) 2017; 220:137-149. [PMID: 27580709 DOI: 10.1111/apha.12795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 06/15/2016] [Accepted: 08/30/2016] [Indexed: 11/30/2022]
Abstract
AIM Antenatal glucocorticoids are used to accelerate foetal lung maturation in babies threatened with premature labour. We examined the influence of glucocorticoids on functional and structural maturation of the central somatosensory pathway in foetal sheep. Somatosensory-evoked potentials (SEP) reflect processing of somatosensory stimuli. SEP latencies are determined by afferent stimuli transmission while SEP amplitudes reveal cerebral processing. METHODS After chronic instrumentation of foetal sheep, mothers received saline (n = 9) or three courses of betamethasone (human equivalent dose of 2 × 110 μg kg-1 betamethasone i.m. 24 h apart, n = 12) at 0.7, 0.75 and 0.8 of gestational age. Trigeminal SEP were evoked prior to, 4 and 24 h after each injection and at 0.8 of gestational age before brains were histologically processed. RESULTS Somatosensory-evoked potentials were already detectable at 0.7 of gestation age. The early and late responses N20 and N200 were the only reproducible peaks over the entire study period. With advancing gestational age, SEP latencies decreased but amplitudes remained unchanged. Acutely, betamethasone did not affect SEP latencies and amplitudes 4 and 24 h following administration. Chronically, betamethasone delayed developmental decrease in the N200 but not N20 latency by 2 weeks without affecting amplitudes. In parallel, betamethasone decreased subcortical white matter myelination but did not affect network formation and synaptic density in the somatosensory cortex. CONCLUSION Somatosensory stimuli are already processed by the foetal cerebral cortex at the beginning of the third trimester. Subsequent developmental decrease in SEP latencies suggests ongoing maturation of afferent sensory transmission. Antenatal glucocorticoids affect structural and functional development of the somatosensory system with specific effects at subcortical level.
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Affiliation(s)
- P. Anegroaie
- Department of Neurology; Jena University Hospital; Jena Germany
- Department of Pediatric Surgery; Jena University Hospital; Jena Germany
| | - M. G. Frasch
- Department of Obstetrics and Gynecology; University of Washington; Seattle WA USA
| | - S. Rupprecht
- Department of Neurology; Jena University Hospital; Jena Germany
| | | | - T. Müller
- Institute of Laboratory Animal Science; Jena University Hospital; Jena Germany
| | - H. Schubert
- Institute of Laboratory Animal Science; Jena University Hospital; Jena Germany
| | - O. W. Witte
- Department of Neurology; Jena University Hospital; Jena Germany
| | - M. Schwab
- Department of Neurology; Jena University Hospital; Jena Germany
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Intra-Amniotic LPS Induced Region-Specific Changes in Presynaptic Bouton Densities in the Ovine Fetal Brain. BIOMED RESEARCH INTERNATIONAL 2015; 2015:276029. [PMID: 26417592 PMCID: PMC4568354 DOI: 10.1155/2015/276029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 12/14/2014] [Indexed: 11/17/2022]
Abstract
Rationale. Chorioamnionitis has been associated with increased risk for fetal brain damage. Although, it is now accepted that synaptic dysfunction might be responsible for functional deficits, synaptic densities/numbers after a fetal inflammatory challenge have not been studied in different regions yet. Therefore, we tested in this study the hypothesis that LPS-induced chorioamnionitis caused profound changes in synaptic densities in different regions of the fetal sheep brain. Material and Methods. Chorioamnionitis was induced by a 10 mg intra-amniotic LPS injection at two different exposure intervals. The fetal brain was studied at 125 days of gestation (term = 150 days) either 2 (LPS2D group) or 14 days (LPS14D group) after LPS or saline injection (control group). Synaptophysin immunohistochemistry was used to quantify the presynaptic density in layers 2-3 and 5-6 of the motor cortex, somatosensory cortex, entorhinal cortex, and piriforme cortex, in the nucleus caudatus and putamen and in CA1/2, CA3, and dentate gyrus of the hippocampus. Results. There was a significant reduction in presynaptic bouton densities in layers 2-3 and 5-6 of the motor cortex and in layers 2-3 of the entorhinal and the somatosensory cortex, in the nucleus caudate and putamen and the CA1/2 and CA3 of the hippocampus in the LPS2D compared to control animals. Only in the motor cortex and putamen, the presynaptic density was significantly decreased in the LPS14 D compared to the control group. No changes were found in the dentate gyrus of the hippocampus and the piriforme cortex. Conclusion. We demonstrated that LPS-induced chorioamnionitis caused a decreased density in presynaptic boutons in different areas in the fetal brain. These synaptic changes seemed to be region-specific, with some regions being more affected than others, and seemed to be transient in some regions.
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Abstract
Despite mounting reports about the negative effects of chronic occupational stress on cognitive functions, it is still uncertain whether and how this type of stress is associated with cerebral changes. This issue was addressed in the present MRI study, in which cortical thickness (Cth) and subcortical volumes were compared between 40 subjects reporting symptoms of chronic occupational stress (38 ± 6 years) and 40 matched controls (36 ± 6 years). The degree of perceived stress was measured with Maslach Burnout Inventory. In stressed subjects, there was a significant thinning of the mesial frontal cortex. When investigating the correlation between age and Cth, the thinning effect of age was more pronounced in the stressed group in the frontal cortex. Furthermore, their amygdala volumes were bilaterally increased (P = 0.020 and P = 0.003), whereas their caudate volumes were reduced (P = 0.040), and accompanied by impaired fine motor function. The perceived stress correlated positively with the amygdala volumes (r = 0.44, P = 0.04; r = 0.43, P = 04). Occupational stress was found to be associated with cortical thinning as well as with selective changes of subcortical volumes, with behavioral correlates. The findings support the hypothesis that stress-related excitotoxicity might be an underlying mechanism, and that the described condition is a stress related illness.
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Affiliation(s)
- Ivanka Savic
- Neurology Clinic, Karolinska University Hospital Department of Women's and Children's Health, Division of Pediatric Neurology, Karolinska Institutet, Stockholm, Sweden
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Blix E, Perski A, Berglund H, Savic I. Long-term occupational stress is associated with regional reductions in brain tissue volumes. PLoS One 2013; 8:e64065. [PMID: 23776438 PMCID: PMC3679112 DOI: 10.1371/journal.pone.0064065] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 04/11/2013] [Indexed: 12/12/2022] Open
Abstract
There are increasing reports of cognitive and psychological declines related to occupational stress in subjects without psychiatric premorbidity or major life trauma. The underlying neurobiology is unknown, and many question the notion that the described disabilities represent a medical condition. Using PET we recently found that persons suffering from chronic occupational stress had limbic reductions in the 5-HT1A receptor binding potential. Here we examine whether chronic work-related stress is also associated with changes in brain structure. We performed MRI-based voxel-based morphometry and structural volumetry in stressed subjects and unstressed controls focusing on gray (GM) and white matter (WM) volumes, and the volumes of hippocampus, caudate, and putamen – structures known to be susceptible to neurotoxic changes. Stressed subjects exhibited significant reductions in the GM volumes of the anterior cingulate cortex and the dorsolateral prefrontal cortex. Furthermore, their caudate and putamen volumes were reduced, and the volumes correlated inversely to the degree of perceived stress. Our results add to previous data on chronic psychosocial stress, and indicate a morphological involvement of the frontostriatal circuits. The present findings of morphological changes in these regions confirm our previous conclusion that symptoms from occupational stress merit careful investigations and targeted treatment.
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Affiliation(s)
- Eva Blix
- Stockholm Brain Institute, Department of Women's and Children's Health, Division of Pediatric Neurology, Karolinska Institute, Stockholm, Sweden
| | | | - Hans Berglund
- Stockholm Brain Institute, Department of Women's and Children's Health, Division of Pediatric Neurology, Karolinska Institute, Stockholm, Sweden
| | - Ivanka Savic
- Stockholm Brain Institute, Department of Women's and Children's Health, Division of Pediatric Neurology, Karolinska Institute, Stockholm, Sweden
- * E-mail:
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Schneider U, Arnscheidt C, Schwab M, Haueisen J, Seewald HJ, Schleussner E. Steroids That Induce Lung Maturation Acutely Affect Higher Cortical Function. Reprod Sci 2010; 18:99-106. [DOI: 10.1177/1933719110381140] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Uwe Schneider
- Department of Obstetrics and Gynecology, University Hospital, Friedrich Schiller University of Jena, Germany
| | - Christian Arnscheidt
- Department of Obstetrics and Gynecology, University Hospital, Friedrich Schiller University of Jena, Germany
| | - Matthias Schwab
- Department of Neurology, University Hospital, Friedrich Schiller University of Jena, Germany
| | - Jens Haueisen
- Biomagnetic Center, Department of Neurology, Friedrich Schiller University Jena, Germany
- Institute of Biomedical Engineering and Informatics, Technical University of Ilmenau, Germany
| | - Hans Joachim Seewald
- Department of Obstetrics and Gynecology, University Hospital, Friedrich Schiller University of Jena, Germany
| | - Ekkehard Schleussner
- Department of Obstetrics and Gynecology, University Hospital, Friedrich Schiller University of Jena, Germany
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Abstract
OBJECTIVE To determine in fetal sheep the effect of betamethasone on myelination in relation to stage of myelination, number of treatment courses, dose, and route of administration. METHODS Fetal expression of myelin basic protein (MBP), a marker of mature oligodendrocytes and myelin, was determined between 0.27 and 0.93 gestation. Short-term betamethasone effects were examined 24 hours after one maternal intramuscular treatment course (weight adjusted to equal the clinical dose of 2 x 8 mg betamethasone to a 70-kg woman) at 0.63, 0.75, and 0.87 gestation or after continuous 48-hour fetal intravenous infusion at 0.75 and 0.87 gestation. Lasting effects were examined 20 days after one and two treatment courses weight-adapted to the clinical dose of 2 x 8 mg or 2 x 12 mg betamethasone at 0.75 gestation. RESULTS Myelin basic protein immunoreactivity was first detected in the internal capsule at 0.53 gestation, followed by the centrum semiovale, the superficial white matter, and corpus callosum at 0.63 gestation. Within 24 hours after treatment, betamethasone reduced the number of mature oligodendrocytes and MBP immunoreactivity. The effect decreased with gestational age. Maternal and fetal betamethasone administration had similar effects. Loss of MBP immunoreactivity was not reversed 20 days after two treatment courses, independent of dose. CONCLUSION Betamethasone-induced delayed cerebral myelination is dependent on the stage of brain development in sheep. Betamethasone-related disturbances in myelination and any potential contribution to childhood behavior deficits need to be confirmed in clinical studies.
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Bruschettini M, van den Hove DLA, Timmers S, Welling M, Steinbusch HP, Prickaerts J, Gazzolo D, Blanco CE, Steinbusch HWM. Cognition- and anxiety-related behavior, synaptophysin and MAP2 immunoreactivity in the adult rat treated with a single course of antenatal betamethasone. Pediatr Res 2006; 60:50-4. [PMID: 16690949 DOI: 10.1203/01.pdr.0000220349.41675.92] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We investigated the effects of a single course of antenatal betamethasone on cognition- and anxiety-related behavior and synaptophysin and microtubule-associated protein 2 (MAP2) immunoreactivity in the adult rat hippocampus. On d 20 of gestation, pregnant rats were injected with either 1) 170 microg/kg body weight of betamethasone ("clinically equivalent dose," equivalent to 12 mg twice, 24 h apart); 2) half this dose; or 3) vehicle. Cognition- and anxiety-related behavior of the offspring was analyzed at an age of 5 mo using the Morris water maze, object recognition task, and open field test. Subsequently, synaptophysin and MAP2 immunoreactivity were measured in the hippocampus. We report no detrimental effects of antenatal betamethasone on cognition- and anxiety-related behavior and synaptophysin immunoreactivity in the adult rat. On the other hand, MAP2 immunoreactivity was decreased by betamethasone in males, suggesting a permanent impairment in the hippocampus. Interestingly, the lower dose appears to have less influence in terms of growth restriction, known to be associated with an increased risk of disease in adulthood. Further research might elucidate whether the betamethasone effect on hippocampal neurons persists later in life and could affect the aging process increasing the risk for neuropathology of the adult.
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Affiliation(s)
- Matteo Bruschettini
- Department of Psychiatry and Neuropsychology, Research Institute Growth and Development, European Graduate School of Neuroscience, University of Maastricht, 6200 MD Maastricht, The Netherlands.
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Bruschettini M, van den Hove DLA, Gazzolo D, Steinbusch HWM, Blanco CE. Lowering the dose of antenatal steroids: the effects of a single course of betamethasone on somatic growth and brain cell proliferation in the rat. Am J Obstet Gynecol 2006; 194:1341-6. [PMID: 16579916 DOI: 10.1016/j.ajog.2005.11.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 11/11/2005] [Accepted: 11/28/2005] [Indexed: 10/24/2022]
Abstract
We investigated the effects of a single course of antenatal betamethasone on neonatal somatic and brain development. On day 20 of gestation, pregnant rats were injected with either with 170 microg kg(-1) body weight of betamethasone ("clinically-equivalent dose," equivalent to 12 mg twice, 24 hours apart) or half this dose or vehicle. Pups (8-11 animals per experimental group per timepoint per gender) were analyzed at 1 (P1), 2, and 21 days after birth. We report that betamethasone induced a significant dose-dependent decrease of somatic measurements in both genders. At P1 cell proliferation was affected by the "clinically equivalent dose" only in the subventricular zone in both genders and in the hippocampus in males. In summary, we show for the first time that a lower dose (equivalent to 6 mg) induces fewer and less severe effects on somatic growth, whereas it does not affect cell proliferation within the brain.
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Affiliation(s)
- Matteo Bruschettini
- Division of Neuroscience, Department of Psychiatry and Neuropsychology, European Graduate School of Neuroscience (EURON), Maastricht, The Netherlands.
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Bruschettini M, van den Hove DLA, Gazzolo D, Bruschettini P, Blanco CE, Steinbusch HWM. A single course of antenatal betamethasone reduces neurotrophic factor S100B concentration in the hippocampus and serum in the neonatal rat. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2005; 159:113-8. [PMID: 16112204 DOI: 10.1016/j.devbrainres.2005.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Revised: 07/20/2005] [Accepted: 07/23/2005] [Indexed: 10/25/2022]
Abstract
The effects of a single course of antenatal betamethasone on S100B protein concentration were investigated in Fisher 344 rats. On day 20 of gestation, pregnant rats were injected twice 8 h apart with either (1) 170 microg kg(-1) body weight betamethasone ("clinically-equivalent dose", equivalent to 12 mg twice, 24 h apart in humans), (2) half of this dose (equivalent to 6 mg) or (3) vehicle. We report reference values for S100B protein in the serum and different brain regions in both genders at 1, 2, and 21 days after birth. Interestingly, S100B concentration showed a time-dependent and brain region-specific pattern of expression. At P1, S100B was higher in the serum of males compared to females. In addition, we show that both doses of betamethasone decreased S100B concentration in the serum of males at P1, whereas in the hippocampus, it was reduced by the clinically-equivalent dose only. This suggests that lowering the dose of antenatal betamethasone may be less detrimental for brain maturation and therefore we reiterate the need for clinical trials with a low dose regimen.
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Affiliation(s)
- Matteo Bruschettini
- Department of Psychiatry and Neuropsychology, Division of Cellular Neuroscience, Faculty of Medicine, University of Maastricht, Maastricht, The Netherlands.
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Löhle M, Müller T, Wicher C, Roedel M, Schubert H, Witte OW, Nathanielsz PW, Schwab M. Betamethasone effects on fetal sheep cerebral blood flow are not dependent on maturation of cerebrovascular system and pituitary-adrenal axis. J Physiol 2005; 564:575-88. [PMID: 15718268 PMCID: PMC1464428 DOI: 10.1113/jphysiol.2004.077537] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Synthetic glucocorticoids are administered to pregnant women in premature labour to accelerate fetal lung maturation at a time when fetal cerebrovascular and endocrine systems are maturing. Exposure to glucocorticoids at 0.8-0.9 of gestation increases peripheral and cerebrovascular resistance (CVR) in fetal sheep. We examined whether the increase of CVR and its adverse effect on cerebral blood flow (CBF) depend on the current level of maturation of the pituitary-adrenal axis and the cerebrovascular system. Using fluorescent microspheres, regional CBF was measured in 11 brain regions before and 24 h and 48 h after the start of 3.3 microg kg(-1) h(-1) betamethasone (n = 8) or vehicle (n = 7) infusions to fetal sheep at 0.73 of gestation. Hypercapnic challenges were performed before and 24 h after the onset of betamethasone exposure to examine betamethasone effects on cerebrovascular reactivity. Betamethasone exposure decreased CBF by approximately 40% in all brain regions after 24 h of infusion (P < 0.05). The decline in CBF was mediated by a CVR increase of 111 +/- 16% in the cerebral cortex and 129 +/- 29% in subcortical regions (P < 0.05). Hypercapnic cerebral vasodilatation and associated increase in CBF were blunted (P < 0.05). Fetal CBF recovered after 48 h of betamethasone administration. There were no differences in glucocorticoid induced CBF and CVR changes compared with our previous findings at 0.87 of gestation. We conclude that the cerebrovascular effects of antenatal glucocorticoids are independent of cerebrovascular maturation and preparturient increase in activity of the fetal pituitary-adrenal axis.
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Affiliation(s)
- Matthias Löhle
- Department of Neurology, Friedrich Schiller University, 07740 Jena, Germany.
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