https://nova.newcastle.edu.au/vital/access/manager/Index ${session.getAttribute("locale")} 5 Microvascular circulatory dysregulation driven in part by cystathionine gamma-lyase: a new paradigm for cardiovascular compromise in the preterm newborn https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:48064 2S may explain the dysregulation of microvascular tone associated with poor outcome following preterm birth. In adult vasculature, H2S is predominantly produced by CSE. We hypothesized that vascular CSE activity contributes to microvascular tone regulation during circulatory transition. Methods: Preterm (GA62) and full‐term (GA69) guinea pig fetuses and neonates were studied. Microvascular blood flow was assessed by laser Doppler flowmetry. Thiosulfate, primary urinary metabolite of H2S, was determined by high‐performance liquid chromatography. Real‐time H2S production was assessed using a microrespiration system in fetal and postnatal (10, 24 hours) skin and heart samples. CSE contribution was investigated by inhibition via propargylglycine. Results: In preterm animals, postnatal H2S production capacity in peripheral vasculature increased significantly and was significantly reduced by the inhibition of CSE. Urinary thiosulfate correlated with both microvascular blood flow and capacity of the vasculature to produce H2S. H2S produced via CSE did not correlate directly with microvascular blood flow. Conclusions: In preterm neonates, H2S production increases during fetal‐to‐neonatal transition and CSE contribution to total H2S increases postnatally. CSE‐dependent mechanisms may therefore underpin the increase in H2S production over the first 72 hours of life in preterm human neonates, associated with both central and peripheral cardiovascular instability.]]> Wed 22 Feb 2023 13:57:01 AEDT ]]> Evaluating changes in GABAergic and glutamatergic pathways in early life following prenatal stress and postnatal neurosteroid supplementation https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:52465 Wed 11 Oct 2023 20:36:57 AEDT ]]> Effects of prenatal stress on fetal neurodevelopment and responses to maternal neurosteroid treatment in guinea pigs https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16551 Wed 11 Apr 2018 17:05:24 AEST ]]> Mechanisms leading to increased risk of preterm birth in growth-restricted guinea pig pregnancies https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16518 62 days) and labor. The PTGS1 expression was significantly upregulated in the myometrium of IUGR animals, and chorionic HPGD expression was markedly decreased (P < .01 and P < .001, respectively). These findings suggest a shift in the balance of PG production over metabolism in IUGR pregnancies leads to a greater susceptibility to preterm birth.]]> Wed 11 Apr 2018 16:46:29 AEST ]]> Changes in neuroactive steroid concentrations after preterm delivery in the guinea pig https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16517 Wed 11 Apr 2018 16:11:20 AEST ]]> Progesterone receptor isoform expression in the guinea pig myometrium from normal and growth restricted pregnancies https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10509 Wed 11 Apr 2018 15:35:47 AEST ]]> A role for H₂S in the microcirculation of newborns: the major metabolite of H₂S (Thiosulphate) is increased in preterm infants. https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16522 Wed 11 Apr 2018 15:22:30 AEST ]]> Interactions of the gasotransmitters contribute to microvascular tone (dys)regulation in the preterm neonate https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:22796 Wed 11 Apr 2018 14:23:39 AEST ]]> The guinea pig as an animal model for studying perinatal changes in microvascular function https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16530 Wed 11 Apr 2018 13:19:47 AEST ]]> Early microvascular changes in the preterm neonate: a comparative study of the human and guinea pig. https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16521 Wed 11 Apr 2018 10:55:59 AEST ]]> Identification of eight different isoforms of the glucocorticoid receptor in guinea pig placenta: relationship to preterm delivery, sex and betamethasone exposure https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29351 Wed 11 Apr 2018 10:29:05 AEST ]]> A Role for H2S in the microcirculation of newborns: the major metabolite of H2S (thiosulphate) is increased in preterm infants https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16029 Wed 11 Apr 2018 10:10:44 AEST ]]> Adaptations in the hippocampus during the fetal to neonatal transition in guinea pigs https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:55878 Wed 03 Jul 2024 14:24:15 AEST ]]> Reduced neurosteroid exposure following preterm birth and its' contribution to neurological impairment: a novel avenue for preventative therapies https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:36900 Wed 02 Mar 2022 14:24:28 AEDT ]]> Effects of prenatal stress on behavioural and neurodevelopmental outcomes are altered by maternal separation in the neonatal period https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:48670 Tue 28 Mar 2023 10:15:40 AEDT ]]> Maternal stress in pregnancy affects myelination and neurosteroid regulatory pathways in the guinea pig cerebellum https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33789 Tue 15 Jan 2019 12:58:06 AEDT ]]> Birth and neonatal transition in the guinea pig: experimental approaches to prevent preterm birth and protect the premature fetus https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:35228 in utero. This allows adverse intrauterine conditions to make a sustained impact on the developing brain like in compromised human pregnancies. In addition, the brain is exposed to a protective neurosteroid environment in utero, which has been suggested to promote development in the guinea pig and the human. Moreover, in utero stresses that have been shown to adversely affect long term neurobehavioral outcomes in clinical studies, can be modeled successfully in guinea pigs. Overall, these parallels to the human have led to increasing interest in the guinea pig for translational studies of treatments and therapies that potentially improve outcomes following adverse events in pregnancy and after preterm birth.]]> Tue 02 Jul 2019 11:37:43 AEST ]]> Disruptions to the cerebellar GABAergic system in juvenile guinea pigs following preterm birth https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:35009 A receptor subunits were measured by RT-PCR. Results: MBP immunostaining was increased in lobule IX of preterm males, and reduced in lobule X of preterm females when compared to their term counterparts. GAD67 staining was decreased in lobule IX and X of the preterm males, but only in lobule X of the preterm females compared to term cohorts for each sex. Internal granule cell layer width of lobule X was decreased in preterm cohorts of both sexes compared to terms. There were no differences between gestational age groups for NeuN staining, GAD67 and GAT1 protein expression as measured by western blotting, or GABAA receptor subunits as measured by RT-PCR between preterm and term for either sex. Conclusions: The present findings suggest that components of the cerebellar GABAergic system of the ex-preterm cerebellum are disrupted. The higher expression of myelin in the preterm males may be due to a deficit in axonal pruning, whereas females have a deficit in myelination at 28 corrected days of age. Together these ongoing alterations may contribute to the neurodevelopmental and behavioural disorders observed in those born preterm.]]> Thu 30 May 2019 14:58:50 AEST ]]> Administration of progesterone throughout pregnancy increases maternal steroids without adverse effect on mature oligodendrocyte immunostaining in the guinea pig https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:36998 Thu 30 Jul 2020 16:59:13 AEST ]]> Loss of neurosteroid-mediated protection following stress during fetal life https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:24307 A receptor subunits that normally heighten neurosteroid sensitivity. These stressors also result in altered placental allopregnanolone metabolism pathways. These findings suggest that reduced neurosteroid production and action in the perinatal period may contribute to some of the adverse neurodevelopmental and behavioural outcomes that result from these pregnancy compromises. Studies examining perinatal steroid supplementation therapy with non-metabolisable neurosteroid analogues to improve these outcomes are warranted.]]> Thu 21 Oct 2021 12:51:39 AEDT ]]> Cerebellar changes in guinea pig offspring following suppression of neurosteroid synthesis during late gestation https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:32953 A receptor subunit composition, which may further limit neurosteroid action. The objective of this study was to determine the effects of suppression of allopregnanolone levels on the markers of development and functional outcome. Pregnant guinea pigs were treated with finasteride at a dose (25 mg/kg maternal weight) shown to suppress allopregnanolone between 60 days of gestation until delivery (term ~71 days). The cerebella from neonates, whose mothers were treated with finasteride or vehicle during pregnancy, were collected at postnatal age 8. Pups that received finasteride displayed significantly greater glial fibrillary acid protein area coverage and reduced GABAA receptor a α₆-subunit messenger RNA within the cerebellum than pups that were exposed to vehicle. These findings indicate that loss of neurosteroid action on the foetal brain in late gestation produces prolonged astrocyte activation and reductions in GABAA receptor a α₆-subunit expression. These changes may contribute to the long-term changes in function associated with preterm birth.]]> Thu 16 Aug 2018 13:35:57 AEST ]]> Increased anxiety-like phenotype in female guinea pigs following reduced neurosteroid exposure in utero https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:32952 Thu 16 Aug 2018 13:35:51 AEST ]]> Stress in pregnancy: a role for neuroactive steroids in protecting the fetal and neonatal brain https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:8296 Sat 24 Mar 2018 08:40:34 AEDT ]]> Changes in human placental 5α-reductase isoenzyme expression with advancing gestation: effects of fetal sex and glucocorticoid exposure https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:8294 Sat 24 Mar 2018 08:40:32 AEDT ]]> Increased expression of alpha-enolase in cervico-vaginal fluid during labour https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:9680 Sat 24 Mar 2018 08:39:14 AEDT ]]> Sex-dependent effect of a low neurosteroid environment and intrauterine growth restriction on foetal guinea pig brain development https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16511 Sat 24 Mar 2018 08:04:17 AEDT ]]> Neuroactive steroids in pregnancy: key regulatory and protective roles in the foetal brain https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16519 Sat 24 Mar 2018 08:01:21 AEDT ]]> 15-hydroxyprostaglandin dehydrogenase expression and localization in guinea pig gestational tissues during late pregnancy and parturition https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:16526 Sat 24 Mar 2018 08:01:18 AEDT ]]> Long-term effects of preterm birth on behavior and neurosteroid sensitivity in the Guinea pig https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30294 Sat 24 Mar 2018 07:33:34 AEDT ]]> Models of perinatal compromises in the guinea pig: their use in showing the role of neurosteroids in pregnancy and the newborn https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29502 Sat 24 Mar 2018 07:29:45 AEDT ]]> Prenatal stress alters hippocampal neuroglia and increases anxiety in childhood https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:26441 A receptor subunit expression was also assessed using RT-PCR. Neonates born from mothers stressed during late pregnancy showed a reduction in both MBP (p < 0.01) and GFAP (p < 0.05) expression in the CA1 region of the hippocampus at 21 days of age. Pups of prenatally stressed pregnancies also showed higher levels of anxiety and neophobic behaviours at the equivalent of childhood (p < 0.05). There were no significant changes observed in allopregnanolone levels, 5αR1/2 expression, or GABAA receptor subunit expression in prenatally stressed neonates compared to controls. This study shows alterations in markers of myelination and reactive astrocytes in the hippocampus of offspring exposed to prenatal stress. These changes are also observed in offspring that show increased anxiety behaviours at the equivalent of childhood, which indicates ongoing structural and functional postnatal changes after prenatal stress exposure.]]> Sat 24 Mar 2018 07:27:17 AEDT ]]> Neurosteroids in the fetus and neonate: potential protective role in compromised pregnancies https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:4813 Sat 24 Mar 2018 07:20:45 AEDT ]]> Severity and timing: how prenatal stress exposure affects glial developmental, emotional behavioural and plasma neurosteroid responses in guinea pig offspring https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:24848 Sat 24 Mar 2018 07:11:25 AEDT ]]> Guinea pig models for translation of the developmental origins of health and disease hypothesis into the clinic https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:44727 Mon 24 Oct 2022 08:12:40 AEDT ]]> Neurosteroid-based intervention using Ganaxolone and Emapunil for improving stress-induced myelination deficits and neurobehavioural disorders https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:47891 Mon 06 Feb 2023 12:21:53 AEDT ]]> Examining Neurosteroid-Analogue Therapy in the Preterm Neonate For Promoting Hippocampal Neurodevelopment https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:50958 Mon 01 Jul 2024 11:10:55 AEST ]]> Prenatal stress induces translational disruption associated with myelination deficits https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:53108 Fri 17 Nov 2023 11:28:01 AEDT ]]> Ongoing effects of preterm birth on the dopaminergic and noradrenergic pathways in the frontal cortex and hippocampus of guinea pigs https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:55359 Fri 17 May 2024 16:05:09 AEST ]]> Impaired Oligodendrocyte Development Following Preterm Birth: Promoting GABAergic Action to Improve Outcomes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:49419 Fri 12 May 2023 15:02:32 AEST ]]> Perinatal compromise contributes to programming of GABAergic and glutamatergic systems leading to long-term effects on offspring behaviour https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:37890 Fri 11 Jun 2021 09:29:09 AEST ]]> Neurosteroid replacement therapy using the allopregnanolone-analogue ganaxolone following preterm birth in male guinea pigs https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:48163 Fri 10 Mar 2023 16:25:45 AEDT ]]> Potential for a cerebellar role in moderate-late preterm associated behavioural disorders https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:54686 Fri 08 Mar 2024 11:53:09 AEDT ]]> Dual isolation of primary neurons and oligodendrocytes from guinea pig frontal cortex https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:54665 Fri 08 Mar 2024 10:57:23 AEDT ]]>