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Introduction Severe hypertension is a common indication for delivery amongst women with pre-eclampsia (PE), contributing to iatrogenic prematurity and its associated complications. Large-conductance calcium-activated potassium channels (BKCa), which promote vasorelaxation, are downstream targets of many vasoactive agents, including nitric oxide and angiotensin II. Estrogen-mediated increases in uterine artery BKCa activity are an important physiological adaptation to normal pregnancy. However, the role of BKCa has not been assessed in the wider systemic vasculature in either normal pregnancy or pregnancy pathologies. Outwith pregnancy, BKCa activity is reduced in association with PE risk factors, including age, hypoxia and diabetes. Furthermore, 5,6-EET, a BKCa inhibitor, is reported to be increased in the serum of women with PE. Objectives To determine the effect of BKCa activation on systemic resistance arteries of pregnant women and whether this is different in PE. Methods Resistance arteries ( Results NS11021 induced a substantial relaxation of omental resistance arteries obtained from women with either NP (N0; final relaxation Control 23 ± 8% Vs. NS11021 76 ± 4%; p Discussion Systemic arteries from women with both NP and PE relax in response to activation of BKCa channels. Direct BKCa activation provides an opportunity to bypass the inherent vascular dysfunction of PE to achieve comparable vasorelaxation in women with PE. On-going work will determine whether BKCa-activating compounds can offer a new treatment for maternal hypertension in PE.

Introduction Calcium channel blockers treat maternal hypertension in pregnancy. The effect of newer calcium channel blockers on placental vascular function remains unknown. This study aimed to determine the effect of calcium channel blockers on placental chorionic plate proximal resistance arteries in comparison to maternal omental arteries. Methods Chorionic plate and omental arteries from healthy term pregnancies delivered by caesarean section were studied using parallel wire myography (n = 80; N = 10). Arteries were normalised at 0.9 of L5.1 kPa in 5% O2 and L13.3 kPa in 20% O2 respectively, approximating physiologic vascular pressure and oxygen tension. Arteries were contracted with thromboxane-mimetic U46619 to determine and maintain optimal physiologic vascular tone (EC80). Nifedipine, Nicardipine and Clevidipine were added in incremental doses from 10–10 M to 10–5 M to create dose-dependent relaxation curves. Omental arteries were incubated for 30 min at the highest dose (10–5 M) to further evaluate full effect (n = 16; N = 4). Results Omental arteries demonstrated similar contractility to chorionic plate arteries (8.90 kPa ± 0.681 vs 8.85 kPa ± 0.603). Chorionic plate arteries did not relax with Nifedipine, Nicardipine or Clevidipine (110.73%± 7.518 vs 118.88%±9.379 vs 113.16%±5.163). Omental arteries demonstrated a trend towards larger relaxation with all calcium channel blockers at the highest dose of drug concentration. This was confirmed with highest dose incubation of omental arteries, that showed Nifedipine, Nicardipine and Clevidipine relaxed omental arteries (52.31%±16.294 vs 57.12%±8.621 vs 79.95%±14.862; One-way ANOVA, p Conclusion Chorionic plate arteries demonstrated reduced vasodilatory responses to calcium channel blockers compared to omental arteries. This suggests calcium channel blockers show limited effect on placental blood flow through proximal resistance arteries.

Objective. To determine if the phosphodiesterase type 5 inhibitor, sildenafil citrate improves endothelial-dependent relaxation of small arteries from women with preeclampsia. Methods. Myometrial and omental biopsies were taken from women participating in a randomized placebo-controlled trial using sildenafil citrate in women with preeclampsia. Vasoconstriction and endothelial-dependent relaxation of small arteries was measured utilizing wire myography. Results. Vasoconstriction and endothelial-dependent relaxation of myometrial and omental arteries were not altered in women taking sildenafil. Conclusion. Acute effects may have been lost as sildenafil administration occurred many hours prior to myography. Plasma sildenafil levels may have been lower than required for vascular response.

This is the first of two articles exploring the use of vignettes as an alternative method of presenting the data arising from interviews. The interviews were carried out as part of research into work-based learning: both articles are based on findings from a hermeneutic phenomenological study into the lived experience of foundation degree mentors and their students—healthcare assistants undertaking a foundation degree in health and social care in order to become assistant practitioners. Part 1 presents a vignette of a notional workplace mentor (Staff Nurse Sophie) that describes her lived experience supporting two equally notional foundation degree students. Sophie’s perspective will be a distillation of data arising from interviews with eight workplace mentors, all employed on acute wards within a large NHS hospital trust. The vignette attempts to demonstrate the role of the workplace mentor in the support of work-based learning, and the interprofessional factors that determine the landscape of workplace learning for foundation degree students. The potential of a vignette to assist in a deeper hermeneutic understanding of meanings arising from data will be explored, and the limitations of the approach considered.

The UK Nuclear Decommissioning Authority (NDA) is a Non Departmental Public Body (NDPB) responsible for the remediation of the UK’s civil nuclear liabilities. To secure government funding and demonstrate that the NDA is delivering its mission, it must be able to show that it provides value for money across its estate. Value comes in many forms, such as an improved environment, hazard reduction, changes in sky line, social amenities, money, employment, and so forth. Depending on the perspective of the receiver, and their closeness to the affected area, the weighting placed on the different aspects of value will vary. Therefore, the challenge has been to get a consistent approach that measures value and is broadly acceptable to stakeholders in which different aspects are compared and decisions are made on a national basis.

Control of vascular resistance and blood flow in the fetoplacental circulation is incompletely understood. Reactive oxygen species (ROS), physiological and pathophysiological regulators of vascular tone, are elevated in preeclampsia (PE), a disease of pregnancy characterized by increased fetoplacental vascular resistance. We tested the hypothesis that ROS modulate vascular reactivity in placental chorionic plate arteries. Wire myography was used to examine (1) the effects of acute exposure to ROS on arterial function in normal pregnancy and (2) the effects of maternal antioxidant supplementation on arterial reactivity in women at high risk for PE participating in the Vitamins in Pre-eclampsia (VIP) trial. ROS generated by xanthine plus xanthine oxidase enhanced basal tension, vasoconstriction in response to the thromboxane mimetic U46619, and relaxation in response to sodium nitroprusside. Hydrogen peroxide and peroxynitrite increased basal tone and relaxed preconstricted arteries (U44619), respectively. In women at risk for PE, chorionic plate artery constriction in response to U46619 was greater in the women receiving placebo compared to the women supplemented with the antioxidant vitamins C and E. ROS may regulate fetoplacental vascular resistance and blood flow in the short term, and chronic exposure to raised ROS could contribute to elevated fetoplacental vascular resistance in PE and fetal growth restriction (FGR).

Agonist-induced tone oscillations (rhythmic contractions and relaxations) occur in vascular beds to allow acute regulation of volume flow and thus the delivery of oxygen and nutrients to the tissue. Mechanisms responsible for the control of human placental vasomotor tone and blood flow are poorly characterized. This study aimed to characterise thromboxane-induced tone oscillations in human placental and myometrial arteries. Chorionic plate and myometrial arteries obtained from biopsies at term were mounted for isometric tension measurement. Tone oscillations were observed in chorionic arteries only when exposed to sub-maximal (

Decreased activity of "oxygen-sensitive" potassium (K) channels reduces hypoxia-induced contraction of pulmonary vascular tissue. "Oxygen-sensitive" channels are present in the fetoplacental vasculature, where vascular resistance is thought to increase in fetal growth restriction (FGR). We assessed placental gene expression of K(V)2.1, K(V)9.3 and K(IR)6.1, three "oxygen-sensitive" K channels in normal pregnancy and FGR.Biopsies were obtained from 12 normal pregnancies and 12 pregnancies complicated by FGR. Chorionic plate arteries and veins were dissected from the biopsies and a sample of placental tissue comprising chorionic plate and villus tissue was also collected. All samples were processed and analyzed using "real time" quantitative RT-PCR.K(V)2.1 and K(V)9.3 gene expression, in veins and placental homogenate, respectively, were increased in FGR. K(IR)6.1 gene expression was comparable in normal pregnancy and FGR samples.The gene expression of two voltage-gated K channels thought to be important for altered vascular reactivity following changes in oxygenation is increased in FGR.

Sphingosine-1-phosphate (S1P) is a potent bioactive lipid that has been implicated in cardiovascular disease. The objective of the present study was to determine the vasoactive effects and underlying mechanisms of S1P on adult human maternal arteries. The isometric tensions of the omental and myometrial arteries isolated from normal pregnant women at term were assessed in response to incremental doses of S1P in the presence or absence of the nitric oxide (NO) synthase inhibitor N(G)nitro-L-arginine methyl ester (L-NAME). The putative involvement of Rho-associated kinases (ROCKs) in intact arteries and in those permeabilized with a-toxin, to study agonist-dependent calcium-sensitization, was assessed with the inhibitor Y27632. Real-time RT-PCR established the presence of mRNA encoding the S1P receptors (S1P 1 to 3 ), previously known as endothelial differentiation gene receptors (EDG1, 3 and 5), in both artery types. S1P induced a dose-dependent increase in the isometric tension of all the arteries. Y27632 reduced constriction due to S1P in intact arteries and reduced S1P-induced sensitization of contraction to submaximal activating Ca 2þ in permeabilized arteries. L-NAME also modulated S1P vasoactive responses in a tissue-specific manner. Two subgroups of omental arteries were identified, one of which utilizes the NO pathway. In myometrial arteries, S1P evoked oscillatory constrictions, whereas pretreatment with L-NAME resulted in only tonic constrictions of unaltered peak magnitude. The prominent vasoactive actions of S1P in the maternal arteries of pregnant women are modulated by inhibitors of ROCKs and NO bioavailability. The subtle tissue-specific functional differences in the modulation of S1P actions by NO have important implications for vascular tone regulation by this bioactive circulatory metabolite during pregnancy. nitric oxide, Rho-associated kinase, vasoconstriction

Poorly controlled diabetes in pregnancy, characterized by hypo- and hyperglycemia, is associated with adverse outcomes. We hypothesized that aberrant glucose levels affect vascular function in pregnancy. The effects of glucose concentration on constriction and endothelium-dependent relaxation in uterine arteries of normal C57BL/6 mice were examined. Ex-vivo arteries from 18 pregnant and 14 non-pregnant mice were mounted on a wire myograph, constricted with phenylephrine and relaxed with incremental doses of acetylcholine, in physiological saline solution containing 5 mmol/L glucose. Arteries were then exposed to solutions with 2, 5, 8 or 12 mmol/L glucose for 30 min and constriction/relaxation repeated. On altering glucose concentrations to 2, 8 or 12 mmol/L, maximal constriction was increased in arteries from pregnant but not from non-pregnant mice (paired t-test, p

Background Adenosine triphosphate (ATP)-sensitive potassium channels (KATP) are important modulators of vascular tone. Preliminary data from our laboratory suggests that KATP channels are expressed in the fetoplacental vasculature where addition of pinacidil, a specific KATP opener, promotes relaxation. We aimed to assess the effects of KRN2391 and KRN4884 on the fetoplacental vasculature, which are putative KATP channel openers. Materials and methods Functional activity of KATP channels was assessed in chorionic plate arteries and veins using wire myography. Cromakalim-, KRN2391- and KRN4884-induced relaxations were assessed in the presence and absence of agonist-induced pretone. Cromakalim, an established KATP channel opener, acted as control. Results KRN2391 evoked significantly greater relaxation of chorionic plate arteries and veins than either KRN4884 or cromakalim. KRN2391-induced relaxation of precontracted arteries and veins was reduced in the presence of inhibitiors of the nitric oxide pathway (L-NNA or LY83583). With KRN4884, there was no contribution of nitric oxide to the induced relaxation. Conclusions We conclude that KATP channels play an important role in controlling placental vascular tone. KRN2391 induces relaxation of human placental blood vessels by activation of KATP channels and via activation of nitric oxide-dependent pathways.

Objective: Maternal obesity pre-programs offspring to develop obesity and associated cardiovascular disease although the underlying mechanism is currently unknown. This study investigated the effect of maternal obesity on perivascular adipose tissue (PVAT) regulation of resistance artery tone. Design and method: 8 week old female SD rats were fed a 10% fat diet (controls) or 45% fat obesogenic diet (HFD) for 12 weeks before mating, then continued on their respective diets during pregnancy and lactation. Male offspring were provided with 10% fat diet until sacrifice at 12 weeks old. PVAT-intact or -denuded mesenteric arteries (250-300μm internal diameter) from offspring were mounted on a wire myograph. Cumulative concentration-response curves were constructed to the thromboxane A2 receptor agonist U46619 (10nM-3μM) ± 10μM A769662, an activator of AMP-activated kinase (AMPK) or 100μM L-NMMA, a nitric oxide synthase (NOS) inhibitor. Results: Body weight, systolic and diastolic blood pressure were significantly increased in HFD dams compared to age-matched controls (391±11 vs 348±12 g; 154±1 vs 145±1 mmHg; 116±1 vs 103±103 mmHg respectively) but no differences were observed between offspring. However, fat pads and insulin levels were increased in both HFD dams versus controls (13.4±1.6 vs 6.5±0.8 g; 1.18±0.09 vs 0.76±0.14 nmol/L respectively) and their offspring (7.2±0.3 vs 6.0±0.2 g; 0.56±0.15 vs 0.17±0.05 nmol/L respectively) versus controls. PVAT exerted an anti-contractile effect in artery segments from offspring of control dams (p Conclusions: In summary, the diminished anti-contractile effects of PVAT in 12 week old offspring of HFD dams may be due to reduced AMPK and nitric oxide activity.

OBJECTIVE: Currently, no investigations reliably identify placental dysfunction in late pregnancy. To facilitate the development of such investigations we aimed to identify placental features that differ between normal and adverse outcome in late pregnancy in a group of pregnancies with reduced fetal movement. METHODS: Following third trimester presentation with reduced fetal movement (N = 100), placental structure ex vivo was measured. Placental function was then assessed in terms of (i) chorionic plate artery agonist responses and length-tension characteristics using wire myography and (ii) production and release of placentally derived hormones (by quantitative polymerase chain reaction and enzyme linked immunosorbant assay of villous tissue and explant conditioned culture medium). RESULTS: Placentas from pregnancies ending in adverse outcome (N = 23) were ~25% smaller in weight, volume, length, width and disc area (all p

Background: The regulation of vascular tone in the uterine circulation is a key determinant of appropriate uteroplacental blood perfusion and successful pregnancy outcome. Estrogens, which increase in the maternal circulation throughout pregnancy, can exert acute vasodilatory actions. Recently a third estrogen receptor named GPER (G protein-coupled estrogen receptor) was identified and, although several studies have shown vasodilatory effects in several vascular beds, nothing is known about its role in the uterine vasculature.Aim: The aim of this study was to determine the function of GPER in uterine arteries mainly during pregnancy. Uterine arteries were isolated from nonpregnant and pregnant rats.Methods: Vessels were contracted with phenylephrine and then incubated with incremental doses (10-12-10-5 M) of the selective GPER agonist G1.Results: G1 induced a dose-dependent vasodilation which was: 1) significantly increased in pregnancy, 2) endothelium-dependent, 3) primarily mediated by NO/cGMP pathway and 4) unaffected by BKca channel inhibition.Conclusion: This is the first study to show the potential importance of GPER signaling in reducing uterine vascular tone during pregnancy. GPER may therefore play a previously unrecognized role in the regulation of uteroplacental blood flow and normal fetus growth.

During pregnancy, trophoblasts migrate from the placenta into uterine spiral arteries, transforming them into wide channels that lack vasoconstrictive properties. In pathological pregnancies, this process is incomplete. To define the fundamental events involved in spiral artery remodeling, we have studied the effect of trophoblasts on vascular smooth muscle cells (SMCs). Here we demonstrate for the first time that apoptosis of SMCs can be initiated by invading trophoblasts. When trophoblasts isolated from normal placenta (primary trophoblasts) or conditioned medium was perfused into spiral or umbilical artery segments, apoptosis of SMCs resulted. Culture of human aortic SMCs (HASMCs) with primary trophoblasts, primary trophoblast-conditioned medium, or a trophoblast-derived cell line (SGHPL-4) also significantly increased SMC apoptosis. Fas is expressed by spiral artery SMCs, and a Fas-activating antibody triggered HASMC apoptosis. Furthermore, a Fas ligand (FasL)-blocking antibody significantly inhibited HASMC apoptosis induced by primary trophoblasts, SGHPL-4, or trophoblast-conditioned medium. Depleting primary trophoblast-conditioned medium of FasL also abrogated SMC apoptosis in vessels in situ. These results suggest that apoptosis triggered by the release of soluble FasL from invading trophoblasts contributes to the loss of smooth muscle from the walls of spiral arteries during pregnancy. Copyright © American Society for Investigative Pathology.

A successful pregnancy is dependent on liberal placental perfusion via the maternal and fetal circulations. Doppler waveform analyses of umbilical arteries suggest increased resistance to flow in the fetoplacental circulation of pregnancies complicated by intrauterine growth restriction (IUGR). Neither the site nor the mediators responsible for this altered vascular reactivity are known, to date. In placentas in normal pregnancy, reduced oxygenation promotes contraction of the in vitro-perfused placental cotyledon and modulates agonist-induced contraction of chorionic plate arteries and veins. Placental oxygenation has also been suggested to be reduced in IUGR. We tested the hypothesis that oxygen tension could directly modify placental chorionic plate vessel vasoreactivity in IUGR. Small arteries and veins from the chorionic plate were dissected from biopsies from placentas of pregnancies complicated by IUGR and were studied using parallel wire myography. Vasoconstriction at 20%, 7%, and 2% oxygen was assessed utilizing the thromboxane mimetic U46619. Experiments were also performed in the presence of 4-aminopyridine (4AP), a blocker of voltage-gated potassium channels. Increased oxygenation reduced venous vasoconstriction but did not modify arterial vasoconstriction. 4AP increased basal tone in arteries and veins. We suggest that venoconstriction in response to hypoxia may provide a mechanism for increased fetoplacental vascular resistance associated with IUGR.

Fetoplacental blood vessel constriction in response to reduced oxygenation has been demonstrated in placenta perfused in vitro. In pulmonary vessels, hypoxic vasoconstriction involves Ca 2+ influx into smooth muscle through membrane ion channels including voltage-gated Ca 2+ channels (VGCCs). We hypothesised that VGCCs are involved in agonist-induced constriction of fetoplacental resistance vessels and that their contribution is modulated by oxygen. Chorionic plate small arteries were studied using wire myography. Arteries were normalised at high (0.9 of L 13.3 kPa ) or low (0.9 of L 5.1 kPa ) stretch and experiments performed at 156, 38 or 15 mmHg oxygen. At low stretch, U46619 (thromboxane-mimetic) or KCl (smooth muscle depolarisation) constriction was greater at 38 than 156 or 15 mmHg oxygen. An L-type VGCC blocker nifedipine, inhibited KCl constriction by >85% but was less effective in U46619 constrictions (43–67%). At high stretch, nifedipine inhibition of KCl- and U46619-induced constriction was less at 15 than 38 or 156 mmHg oxygen. Oxygen did not affect constriction to U46619 or nifedipine-induced relaxation when vessels were normalised at high stretch. In conclusion, oxygen modulates chorionic plate arterial constriction at low stretch but regulation is lost at high stretch. U46619 constriction is underlain by VGCCs and nifedipine-insensitive processes; their relative contribution is influenced by oxygen.

Objective Endothelial dysfunction is central to the pathogenesis of pre-eclampsia (PE). This study aimed to determine if maternal characteristics, such as age, parity, BMI, smoking status and obstetric history, which affect the risk of developing pre-eclampsia, influenced endothelial function in myometrial arteries taken during an uncomplicated pregnancy. Study design As part of ongoing studies investigating endothelial function in normal and compromised pregnancies, myometrial vessels were isolated from biopsies taken at elective Caesarean section. A cohort of 119 women was identified and information regarding past pregnancy outcomes and medical history was obtained. Wire myography was used to compare endothelial-dependent relaxation in response to bradykinin between different patient groups. Results Maternal age, parity and a history of miscarriage did not affect endothelial-dependent relaxation of myometrial small arteries. Attenuated endothelial-dependent relaxation was seen in vessels taken from women with elevated BMI and enhanced relaxation was seen in women who had smoked during pregnancy. Vessels isolated from women with a history of past pregnancy complications did not show any significant difference in endothelial-dependant relaxation compared to women with uncomplicated histories. Conclusion Maternal factors may influence endothelial function in the absence of pregnancy complications. Endothelial-dependent relaxation of myometrial arteries, isolated from multiparous women with an uncomplicated index pregnancy, is comparable between women with and without a history of pregnancy complications.

Fetoplacental blood vessels constrict in response to endothelin (ET-1) or reduced oxygen tension in the placental cotyledon perfused in vitro. In nonplacental resistance arteries, hypoxia and ET-1 induce constriction by promoting Ca2+ influx into smooth muscle through membrane ion channels, which include voltage-gated Ca2+ channels (VGCCs). We hypothesized that VGCCs are involved in ET-1-induced constriction of fetoplacental resistance vessels and that their contribution to constriction is enhanced at low oxygen tension.Chorionic plate small arteries from term placentas were studied using parallel wire myography. Arteries were normalized at 0.9 of L(5.1 kPa) ("low stretch" approximately 25 mm Hg; approximating physiologic vascular pressure) or 0.9 of L(13.3 kPa) ("high stretch" approximately 42 mm Hg) and experiments performed at oxygen tensions of 156, 38, and 15 mm Hg.When chorionic plate arteries were normalized at low stretch, oxygen tension did not affect constriction to ET-1. Nifedipine (10(-4) M), a blocker of L-type VGCCs, inhibited ET-1 (EC80)-induced constriction to a similar extent at each oxygen tension (52% to 64% inhibition). In contrast, when arteries were normalized at high stretch, constriction to ET-1 was greater at 38 than at 156 or 15 mm Hg oxygen and nifedipine inhibition of ET-1-induced constriction was greater at 38 and 15 mm Hg than at 156 mm Hg oxygen.VGCCs and nifedipine-insensitive processes underlie the contractile response of chorionic plate arteries to ET-1 and their relative contribution to vasoconstriction is modulated by oxygen tension when vessels are normalized at high stretch. However, contrary to our hypothesis, the response of chorionic plate arteries to ET-1 is not modulated by oxygen when vessels are normalized at physiologic pressure.

Blood flow control within the fetoplacental circulation is poorly understood despite the essential role of the placenta in pregnancy. Our study compared an in vitro assessment of placental chorionic plate small artery function with in vivo measures of umbilical artery blood flow. Umbilical artery Doppler waveform analysis was performed on women (N=8) with uncomplicated pregnancies within 24 hours of delivery. Small arteries (n=25) were dissected from the placental chorionic plate from biopsies at term and studied using parallel wire myography. Chorionic plate arteries developed maintained constrictions to the thromboxane-mimetic U46619. Nitric oxide (NO) donation with the endothelial-independent agent sodium nitroprusside elicited significant relaxation compared to paired control vessels. This vasodilatation correlated significantly with both pulsatility and resistance indices measured in the umbilical artery. We conclude that Doppler indices in the umbilical artery are inversely proportional to the maximal relaxation achieved by chorionic plate small arteries in response to a NO donor.

Aim. This was an investigation to discover the lived experience of men with lower urinary tract symptoms arising from benign prostatic hyperplasic. Design. A hermeneutic phenomenological study. Methods. Approval was granted by the local Applied and Qualitative Research Ethics Committee (AQREC) prior to the commencement of the study. Data were gathered via semi-structured interviews that were audio taped, and subsequently transcribed. Each transcripted interview was analysed by the investigator and a team of ‘expert readers’. The team agreed on a total of 57 sub-themes divided into seven categories with unanimity, therefore obviating the need for participant validation. Findings. The major findings of the study suggest that men experience a broad and dramatic spectrum of phenomena while living with a benign prostate condition. This includes profound embarrassment, fear, revulsion as well as humour that require a range of methods and life adjustments to manage and contain their symptoms. Conclusions. The participant's narratives provide a thick, rich and meaningful insight into how men understand their bodies, and make sense of prostate disease; a significant men's health issue. Relevance to clinical practice. Several studies have already been published describing men's lived experience of prostate surgery for benign prostatic hyperplasia. This research has captured men's lived experience of lower urinary tract symptoms ahead of surgical intervention. Men experience a broad scope of phenomena resulting from life with a benign prostate condition that encompasses fear and embarrassment and the development of coping mechanisms and changes in life style. Recent media awareness campaigns to raise public awareness of prostate disease as a men's health issue appear to be changing how men perceive their bodies, how they converse with one another, and their help seeking behaviour.

We tested the hypothesis that crossing two mouse models of fetal growth restriction (FGR) of differing phenotype would induce more severe FGR than either model alone. Female endothelial nitric oxide synthase knockout mice (eNOS−/−) were mated with placental-specific Igf2 knockout males (P0). Resultant fetuses were no more growth restricted than those with P0 deletion alone. However, P0 deletion attenuated the reduced placental system A amino acid transporter activity previously observed in eNOS−/− mice. Manipulating maternal and fetal genotypes provides a means to compare maternal and fetal regulation of fetal growth.

Iron handling and gene expression of the divalent metal transporter, DMT1, in the kidney of the anemic Belgrade (b) rat.BackgroundWe have previously shown that the rat kidney reabsorbs metabolically significant amounts of iron and that it expresses the divalent metal transporter 1, DMT1. The Belgrade (b) rat carries a mutation in DMT1 gene, which causes hypochromic, microcytic anemia due to impaired intestinal iron absorption and transport of iron out of the transferrin cycle endosome. In the duodenum of b/b rats, expression of DMT1 mRNA and protein is increased, suggesting a feedback regulation by iron stores. The aim of this study was to investigate iron handling and DMT1 expression in the kidneys of Belgrade rats.MethodsAnimals were maintained for 3 weeks on a synthetic diet containing 185mg/kg iron (FeSO4), after which functional and molecular parameters were analyzed in male heterozygous (+/b) and homozygous (b/b) rats (N = 4 to 6 for each group).ResultsSerum iron concentration was significantly higher in b/b compared to +/b rats while urinary iron excretion rates were unchanged in b/b compared to +/b rats. Northern analysis using a rat DMT1 probe showed comparable mRNA levels between +/b and b/b animals. Western analysis and immunofluorescence microscopy performed using a polyclonal antibody against rat DMT1 showed that DMT1-specific immunoreactivity was almost absent in the kidneys of b/b rats compared to that seen in +/b animals.ConclusionOur results indicate that the G185R mutation of DMT1 causes protein instability in the kidneys of b/b rats. Given that +/b and b/b rats excrete comparable amounts of iron, the lack of DMT1 protein is compensated by an alternative, yet to be identified, mechanism.

The control of the blood flow within the fetoplacental circulation is poorly understood despite the essential role of the placenta in pregnancy. Our aim was to assess the vasoactive responses of veins from the placental chorionic plate. Biopsies were obtained from term placentae from uncomplicated pregnancies. Small veins from the chorionic plate were dissected free from surrounding tissue and studied using parallel wire myography. Human placental chorionic plate veins developed maintained constrictions to the thromboxane-mimetic U46619. Endothelium-dependent agonists did not promote venous relaxation. However, NO donation with the endothelial-independent agent, sodium nitroprusside, elicited significant relaxation. Venous constriction to U46619 and relaxation to sodium nitroprusside were modified by adjustment of media oxygen tension and normalization parameters. Human placental chorionic plate veins respond to vasoactive agents and may play a role in the control of the blood flow in the fetoplacental circulation.

The proliferation of nurstHed Initiatives arising from nurse specialist/practitioner posts In urology Is reflected In areas such as the management of bladder cancer, erectile dysfunction, stoma care, and prostate disease. The establishment of the role of urology specialist nurse In one North Oxfordshlre hospital led to the development of a nurstHed prostate assessment clinic for male patients with lower urinary tract symptoms arising from benign prostatic hyperplasia. A description of how training was conducted, and the subsequent reappraisal of competency, Is given In relation to physical examination and history-taking skills necessary for the development of this Initiative.

Despite the essential role of the placenta in pregnancy, the control of the blood flow within the fetoplacental circulation is poorly understood. A handful of myography studies have directly assessed the role of vasoactive agonists in fetoplacental vasculature contractility but have used a range of steady-state conditions. Our aim, therefore, was to determine the optimal vessel diameter and oxygen tension to assess vascular function in small arteries isolated from the chorionic plate of normal term placentae. Biopsies were obtained from term placentae from uncomplicated pregnancies. Small arteries were dissected from the chorionic plate, mounted onto a wire myograph in HCO3(-) -buffered physiological salt solution at 37 degrees C and equilibrated for 20 min. Two methods for normalization of the optimal length/diameter for contractility of chorionic plate small arteries were assessed. Both classical normalization (CN) and length-tension curve (LTC) methods produced similar data. These data were agonist-independent. Data for CN and LTC were unaffected but maximal force generation (for U46619) was decreased in reduced oxygen tensions. Using conditions for optimal tension production in chorionic plate small arteries the thromboxane-mimetic U46619 produced the greatest and most reproducible constrictive effect. Relaxations were only achieved with endothelial-independent agonists (sodium nitroprusside and papaverine).

Increased vascular resistance and reduced fetoplacental blood flow are putative aetiologies in the pathogenesis of fetal growth restriction (FGR); however, the regulating sites and mechanisms remain unclear. We hypothesised that placental vessels dictate fetoplacental resistance and in FGR exhibit endothelial dysfunction and reduced flow-mediated vasodilatation (FMVD). Resistance was measured in normal pregnancies (n = 10) and FGR (n = 10) both in vivo by umbilical artery Doppler velocimetry and ex vivo by dual placental perfusion. Ex vivo FMVD is the reduction in fetal-side inflow hydrostatic pressure (FIHP) following increased flow rate. Results demonstrated a significant correlation between vascular resistance measured in vivo and ex vivo in normal pregnancy, but not in FGR. In perfused FGR placentas, vascular resistance was significantly elevated compared to normal placentas (58 ± 7.7 mmHg and 36.8 ± 4.5 mmHg, respectively; 8 ml min−1; means ± SEM; P

Obese women (body mass index ≥30 kg/m(2)) are at greater risk than normal weight women of pregnancy complications associated with maternal and infant morbidity, particularly the development of cardiovascular disease and metabolic disorders in later life; why this occurs is unknown. Nonpregnant, obese individuals exhibit systemic vascular endothelial dysfunction. We tested the hypothesis that obese pregnant women have altered myometrial arterial function compared to pregnant women of normal (18-24 kg/m(2)) and overweight (25-29 kg/m(2)) body mass index. Responses to vasoconstrictors, U46619 (thromboxane mimetic) and arginine vasopressin, and vasodilators, bradykinin and the nitric oxide donor sodium nitroprusside, were assessed by wire myography in myometrial arteries from normal weight (n = 18), overweight (n = 18), and obese (n = 20) women with uncomplicated pregnancies. Thromboxane-prostanoid receptor expression was assessed using immunostaining in myometrial arteries of normal weight and obese women. Vasoconstriction and vasodilatation were impaired in myometrial arteries from obese women with otherwise uncomplicated pregnancies. Disparate agonist responses suggest that vascular function in obese women is not globally dysregulated but may be specific to thromboxane and nitric oxide pathways. Because obesity rates are escalating, it is important to identify the mechanisms underlying impaired vascular function and establish why some obese women compensate for vascular dysfunction and some do not. Future studies are needed to determine whether central adiposity results in an altered endocrine milieu that may promote vascular dysfunction by altering the function of perivascular adipose tissue.

Obese women (body mass index ≥30 kg/m(2)) are at greater risk than normal weight women of pregnancy complications associated with maternal and infant morbidity, particularly the development of cardiovascular disease and metabolic disorders in later life; why this occurs is unknown. Nonpregnant, obese individuals exhibit systemic vascular endothelial dysfunction. We tested the hypothesis that obese pregnant women have altered myometrial arterial function compared to pregnant women of normal (18-24 kg/m(2)) and overweight (25-29 kg/m(2)) body mass index. Responses to vasoconstrictors, U46619 (thromboxane mimetic) and arginine vasopressin, and vasodilators, bradykinin and the nitric oxide donor sodium nitroprusside, were assessed by wire myography in myometrial arteries from normal weight (n = 18), overweight (n = 18), and obese (n = 20) women with uncomplicated pregnancies. Thromboxane-prostanoid receptor expression was assessed using immunostaining in myometrial arteries of normal weight and obese women. Vasoconstriction and vasodilatation were impaired in myometrial arteries from obese women with otherwise uncomplicated pregnancies. Disparate agonist responses suggest that vascular function in obese women is not globally dysregulated but may be specific to thromboxane and nitric oxide pathways. Because obesity rates are escalating, it is important to identify the mechanisms underlying impaired vascular function and establish why some obese women compensate for vascular dysfunction and some do not. Future studies are needed to determine whether central adiposity results in an altered endocrine milieu that may promote vascular dysfunction by altering the function of perivascular adipose tissue.

We have demonstrated that the kidney plays an important role in iron balance and that metabolically significant reabsorption of this ion occurs in the loop of Henle and the collecting ducts [Wareing M, Ferguson CJ, Green R, Riccardi D, and Smith CP. J Physiol (Lond) 524: 581–586, 2000]. To test the possibility that the divalent metal transporter DMT1 (Gunshin H, Mackenzie B, Berger UV, Gunshin Y, Romero MF, Boron WF, Nussberger S, Gollan JL, and Hediger MA. Nature 388: 482–488, 1997) could represent the apical route for iron entry in the kidney, we raised and affinity-purified an anti-DMT-1 polyclonal antibody and determined DMT-1 distribution in rat kidney by Western analysis, immunofluorescence, and confocal microscopy. The strongest DMT1-specific (i.e., peptide-protectable) immunoreactivity was found in the collecting ducts, in both principal and intercalated cells. Thick ascending limbs of Henle's loop and, more intensely, distal convoluted tubules exhibited apical immunostaining. Considerable intracellular DMT-1 immunoreactivity was seen throughout the nephron, particularly in S3 segments. The described distribution of DMT-1 protein is in agreement with our previous identification of nephron sites of iron reabsorption, suggesting that DMT-1 provides the molecular mechanism for apical iron entry in the distal nephron but not in the proximal tubule. Basolateral iron exit may be facilitated by a different system.

A luminal microperfusion technique was used to examine the K+ permeability of surface proximal convoluted tubules (PCT) in the kidney of anesthetized rats. Transtubular potassium concentration ([K+]) gradients were varied by altering the concentration of KCl in luminal perfusates, to which 32 mmol/l of the impermeant solute raffinose was also added to prevent net fluid reabsorption. The arithmetic mean transtubular [K+] gradient was highly predictive of net potassium flux, yielding an apparent K+ permeability of 31.9 ± 1.7 × 10−5 cm/s in the absence of fluid reabsorption. When compared using identical calculation techniques, we found this was not significantly different from the permeability derived in a previous study when fluid reabsorption was present [J. D. Kibble, M. Wareing, R. W. Wilson, and R. Green. Am. J. Physiol. 268 ( Renal Fluid Electrolyte Physiol. 27): F778–F783, 1995]. We conclude that fluid reabsorption does not affect the apparent permeability of the proximal tubule to potassium. The apparent permeability to86Rb, measured following its addition to luminal perfusates, was not significantly different from the value obtained for K+, suggesting that rubidium is a useful marker for net potassium movements in the PCT of the rat.

Fetal growth restriction (FGR) is a serious pregnancy complication, resulting in significant perinatal morbidity and mortality. Increased vascular resistance in the fetoplacental circulation is a hallmark of FGR and is associated with enhanced vasoconstriction of the resistance arteries in the placenta, the chorionic plate arteries (CPAs). Although the cause is unknown, FGR is associated with excess exposure to glucocorticoids (GCs), key mediators of vascular resistance in the systemic circulation. We hypothesized that GCs alter CPA reactivity, thereby contributing to the altered blood flow dynamics seen in FGR. We aimed to examine the acute and chronic effects of GCs on CPA reactivity and the operational mechanisms. Glucocorticoid receptors were highly expressed by CPA. 11β-Hydroxysteroid isoenzyme type 2 was detected within the endothelium, whereas 11β-hydroxysteroid isoenzyme type 1 was absent. Acute GC treatment significantly attenuated U46619-induced constriction. This effect was reversed by cotreatment with mifepristone or an endothelial NOS inhibitor. In contrast, chronic GC treatment potentiated U46619 constriction in a dose-dependent manner, which was partially abolished by mifepristone cotreatment. Similar effects were observed using a novel nonsteroidal glucocorticoid receptor-specific agonist. Chronic treatment with GCs altered the expression of several vasoactive factors, including thromboxane and bradykinin receptors, prokineticin-1, cyclooxygenase-2, and endothelial NOS. In summary, acute and chronic GC treatment exerts contrasting effects on CPA vasoreactivity. These opposing effects are consistent with temporal actions in other vascular beds and reflect activation of distinct nongenomic and genomic pathways. Chronic exposure to elevated GCs may contribute to the raised vascular resistance observed in the fetoplacental circulation in FGR.

239 PDE5 inhibition ameliorates visceral adiposity targeting the miR-22 / SIRT1 pathway: evidence from the CECSID trial {#article-title-2} Background: Visceral adipose plays a significant role in cardiovascular risk. PDE5 inhibitors (PDE5i) can improve cardiac function and insulin sensitivity in type 2 diabetic patients (T2DM). Purpose: To investigate whether PDE5i affect visceral adipose tissue (VAT), specifically epicardial fat (EAT), and what the mechanism involved using microarray-based profiling of pharmacologically modulated miRNAs. Methods: a randomized, double-blid, placebo-controlled study was designed in T2DM. 59 diabetic patients were randomized to receive 100 mg/d Sildenafil or Placebo for 12 weeks. Fat biopses were performed in a subgroup of patients. In a parallel animal study, db/db mice were randomized to 12.week Sildenafil or vehicle and VAT was collected. Main outcomes and measures were anthropometric and metabolic parameters, EAT quantification through cardiac magnetic resonance imaging (CMR), array of circulating 2005 miRNAs, qPCR and flow cytometry of VAT. Results: Compared to Placebo, Sildenafil reduced waist circumference (p=0.024) an EAT by CMR (p =0.045). Microarray analysis identified some miRNAs differentially regulate by Sildenafil, among which a downregulation of miR-22-3p, confirmed by real-time qPCR (p

Introduction Maternal obesity programmes offspring to develop obesity and associated cardiovascular disease. Perivascular adipose tissue (PVAT) exerts an anti-contractile effect in healthy blood vessels; an effect lost in male offspring of obese dams. However, the mechanism by which maternal obesity programmes PVAT dysfunction in offspring remains unknown. Methods Six week old female Sprague-Dawley rats were fed a control (10% fat) or 45% fat obesogenic diet (HFD) for 12 weeks before mating; during pregnancy and lactation. At weaning, female offspring were provided with the control diet until sacrifice at either 12 (12 wo) or 24 (24 wo) weeks of age. PVAT-denuded mesenteric arteries from pups, with or without exogenous PVAT, were mounted on a wire myograph and concentration-response curves were constructed to thromboxane A2 receptor agonist U46619 (10 nM-3 µM) ± 10 µM A769662, an activator of AMP-activated protein kinase (AMPK) ± glucosamine (an O-GlcNAcylator). Western blotting was used to asses protein expression in PVAT stimulated with or without glucosamine. Results Body weight, insulin levels and blood pressure were increased in HFD dams and their 12wo and 24 wo offspring compared to age-matched controls. Without PVAT, vessel contractions to U46619 were reduced in 12 wo offspring of HFD dams, effects mimicked in control arteries by pre-incubation with 10 mM glucosamine. PVAT from control, but not from HFD offspring, exerted an anti-contractile effect on the corresponding PVAT-denuded arteries at both ages. Pre-incubation of control PVAT with glucosamine diminished the anti-contractile effect at both ages. PVAT from HFD offspring pre-incubated with glucosamine had no effect on PVAT-denuded vessels but simultaneous AMPK activation within PVAT partially restored anti-contractile capability at both ages. Protein O-GlcNAcylation expression was increased in HFD PVAT and control PVAT incubated with glucosamine, whereas AMPK expression was decreased. Conclusions The enhanced protein O-GlcNAcylation and decreased AMPK expression in HFD PVAT may underlie the reduced anti-contractile effect of PVAT in female offspring of obese dams. Nevertheless, simultaneous AMPK activation within HFD PVAT partially restored the anti-contractile effects of PVAT.

The role of diffusion in transepithelial potassium flux and the importance of potassium channels in the luminal cell membrane to this process were examined by applying a luminal microperfusion technique to surface tubules in kidneys of anesthetized rats. Potassium concentration gradients were applied by altering the concentration of KCl in perfusates. To some perfusates, 2 mmol/l BaCl2 was added to block potassium channels in the luminal cell membrane. The mean applied potassium concentration gradient was highly predictive of net potassium transport in the absence of any change in fluid reabsorption, with an apparent potassium permeability of 22 x 10(-5) cm/s. Thus potassium transport in the proximal tubule may have an important diffusive component. Luminal barium significantly reduced the concentration of potassium in collected fluid under conditions of net potassium secretion, although a substantial barium-insensitive potassium permeability was also observed. However, the site of action of luminally applied barium is uncertain in proximal tubule, since barium was reabsorbed by the tubule at a rate of 13.6 pmol.mm-1.min-1. We conclude that diffusion is a significant driving force for potassium reabsorption in proximal tubule and that most diffusive potassium transport occurs via a barium-insensitive route, possibly the paracellular pathway.

The potency of adult-derived circulating progenitor endothelial colony forming cells (ECFCs) is drastically surpassed by their fetal counterparts. Human pregnancy is associated with robust intensification of blood flow and vascular expansion in the uterus, crucial for placental perfusion and fetal supply. Here, we investigate whether fetal ECFCs transmigrate to maternal bloodstream and home to locations of maternal vasculogenesis, primarily the pregnant uterus. In the first instance, endothelial-like cells, originating from mouse fetuses expressing paternal eGFP, were identified within uterine endothelia. Subsequently, LacZ or enhanced green fluorescent protein (eGFP)-labeled human fetal ECFCs, transplanted into immunodeficient (NOD/SCID) fetuses on D15.5 pregnancy, showed similar integration into the mouse uterus by term. Mature endothelial controls (human umbilical vein endothelial cells), similarly introduced, were unequivocally absent. In humans, SRY was detected in 6 of 12 myometrial microvessels obtained from women delivering male babies. The copy number was calculated at 175 [IQR 149–471] fetal cells per millimeter square endothelium, constituting 12.5% of maternal vessel lumina. Cross-sections of similar human vessels, hybridized for Y-chromosome, positively identified endothelial-associated fetal cells. It appears that through ECFC donation, fetuses assist maternal uterine vascular expansion in pregnancy, potentiating placental perfusion and consequently their own fetal supply. In addition to fetal growth, this cellular mechanism holds implications for materno-fetal immune interactions and long-term maternal vascular health.

Human placental expression of K(V)9.3, a voltage-gated K channel linked to tissue oxygenation responses, has been suggested at the messenger RNA level but tissue localisation has not been described. We aimed to: (1) produce an antibody to human K(V)9.3 and (2) assess channel expression and distribution in human placental tissue. We determined human placental protein expression and localisation using an antibody to K(V)9.3. Antibody specificity was confirmed by Western blotting. Staining was observed in syncytiotrophoblast microvillous membrane, endothelial cells (in intermediate, stem villi and chorionic plate blood vessels) and vascular smooth muscle cells (large diameter vessels only) by immunohistochemistry. Expression was unchanged in tissue from women with small-for-gestational age babies. It was concluded that K(V)9.3 is localised to human placental vascular tissues and syncytiotrophoblast.

The UK Nuclear Decommissioning Authority (NDA) is a Non Departmental Public Body (NDPB) responsible for the remediation of the UK’s civil nuclear liabilities. To secure government funding and demonstrate that the NDA is delivering its mission, it must be able to show that it provides value for money across its estate. Value comes in many forms, such as an improved environment, hazard reduction, changes in sky line, social amenities, money, employment, and so forth. Depending on the perspective of the receiver, and their closeness to the affected area, the weighting placed on the different aspects of value will vary. Therefore, the challenge has been to get a consistent approach that measures value and is broadly acceptable to stakeholders in which different aspects are compared and decisions are made on a national basis.

The increasing number of mouse models of fetal growth restriction (FGR) make it crucial to standardize the way FGR is defined. By constructing growth curves in the placental-specific Igf2 knockout mouse (P0) it was demonstrated that 93% of P0 fetuses fell below the 5th centile of wild-type weights at E18.5, up from 44% at E16.5. This analysis, coupled with anthropomorphic measurements showing evidence of head sparing in P0 fetuses, allows clinical comparisons of FGR in mice through the use of clinically relevant growth curves. We suggest this as a standardized approach to defining FGR in mouse, and other animal models.

Statins can have beneficial cholesterol-independent effects on vascular contractility, which may involve increases in the bioavailability of NO (nitric oxide) as a result of phosphorylation of eNOS (endothelial NO synthase). Although this has been attributed to phosphorylation of Akt (also known as protein kinase B), studies in cultured cells have shown that statins can phosphorylate AMPK (AMP-activated protein kinase); it is unknown whether this has functional effects in intact arteries. Thus we investigated the acute effects of simvastatin on resistance arterial contractile function, evaluating the involvement of NO, Akt and AMPK. Isolated rat mesenteric resistance arteries were mounted on a wire myograph. The effects of incubation (1 and 2 h) with simvastatin (0.1 or 1 μM) on contractile responses were examined in the presence and absence of L-NNA (N-nitro-L-arginine; 10 μM) or mevalonate (1 mM). Effects on eNOS, phospho-eNOS (Ser1177), and total and phospho-Akt and -AMPK protein expression were investigated using Western blotting. The effect of AMPK inhibition (compound C, 10 μM) on eNOS phosphorylation and contractile responses were also studied. Simvastatin (1 μM, 2 h) significantly reduced constriction to U46619 and phenylephrine and enhanced dilations to ACh (acetylcholine) in depolarized, but not in U46619-pre-constricted arteries. These effects were completely and partially prevented by L-NNA and mevalonate respectively. Simvastatin increased eNOS and AMPKα phosphorylation, but had no effect on Akt protein expression and phosphorylation after 2 h incubation. Compound C prevented the effects of simvastatin on eNOS phosphorylation and contractility. Thus simvastain can acutely modulate resistance arterial contractile function via mechanisms that involve the AMPK/phospho-eNOS (Ser1177)/NO-dependent pathway.

Workshops are an important part of the IFPA annual meeting. At IFPA Meeting 2010 there were twelve themed workshops, six of which are summarized in this report. 1. The immunology workshop focused on normal and pathological functions of the maternal immune system in pregnancy. 2. The transport workshop dealt with regulation of ion and water transport across the syncytiotrophoblast of human placenta. 3. The epigenetics workshop covered DNA methylation and its potential role in regulating gene expression in placental development and disease. 4. The vascular reactivity workshop concentrated on methodological approaches used to study placental vascular function. 5. The workshop on epitheliochorial placentation covered current advances from in vivo and in vitro studies of different domestic species. 6. The proteomics workshop focused on a variety of techniques and procedures necessary for proteomic analysis and how they may be implemented for placental research.