Dilatation of the ductus arteriosus by diazoxide in fetal and neonatal rats.

Background: Diazoxide, an ATP-sensitive potassium channel opener, is the main therapeutic agent for treating hyperinsulinemic hypoglycemia. The aim of this study was to determine the in vivo ductus arteriosus (DA)-dilating effects of diazoxide in fetal and neonatal rats.

Methods: Near-term rat pups delivered via cesarean section were housed at 33°C.

Cardiovascular anomalies associated with chromosome 22q11.2 deletion syndrome.

Cardiovascular anomalies are present in 80% of neonates with 22q11.2 deletion syndrome. Three genes in chromosome 22q11.

In vivo dilatation of the ductus arteriosus induced by furosemide in the rat.

Furosemide increases prostaglandin production and may be associated with patent ductus arteriosus (PDA). We aimed to clarify the in vivo ductus-dilating effects of furosemide in neonatal rats. Near-term rat pups delivered by a cesarean section were housed at 33 degrees C.

Phenotype-genotype correlation in a patient with co-occurrence of Marfan and LEOPARD syndromes.

Here we report on a patient with multiple lentigines, hypertelorism, short stature, arachnodactyly, scoliosis, dissecting aneurysm, hypertrophic cardiomyopathy and developmental delay, and a family history of Marfan syndrome. The patient is affected with both Marfan and LEOPARD syndromes. Mutational screening of the FBN1 gene showed a c.

Fetal reversed constrictive effect of indomethacin and postnatal delayed closure of the ductus arteriosus following administration of transplacental magnesium sulfate in rats.

Background: Magnesium sulfate (MgSO4) is used therapeutically for eclampsia and tocolysis. Some reports have suggested a relationship between therapeutic MgSO4 and patent ductus arteriosus (DA) in preterm infants.

Objectives: To clarify patent DA induction by MgSO4 in preterm infants, we studied the increase in serum Mg concentrations and fetal dilatation and postnatal delayed closure of the ductus, using transplacental MgSO4 in rats.

Delayed neonatal closure of the ductus arteriosus following early in utero exposure to indomethacin in the rat.

Background: Indomethacin is used to close the patent ductus arteriosus in premature infants and for tocolysis of preterm labor. Clinically and experimentally, early in utero exposure to indomethacin induces the paradoxical delay of postnatal closure of the ductus arteriosus.

Objectives: To clarify the pharmacological nature of the delay of closure of the ductus arteriosus in the rat.

In vivo dilatation of the ductus arteriosus by Rho kinase inhibition in the rat.

Background: Fasudil hydrochloride, a Rho kinase inhibitor, was reported to dilate the constricted ductus arteriosus in vitro, and was suggested as a neonatal bridge to heart surgery.

Objectives: To clarify the in vivo effectiveness of fasudil to dilate the neonatal ductus arteriosus, and its usefulness as a bridge to heart surgery.

Methods: We studied the dose and timing of administration of fasudil in the neonatal rat.

Germline gain-of-function mutations in RAF1 cause Noonan syndrome.

Noonan syndrome is characterized by short stature, facial dysmorphia and a wide spectrum of congenital heart defects. Mutations of PTPN11, KRAS and SOS1 in the RAS-MAPK pathway cause approximately 60% of cases of Noonan syndrome. However, the gene(s) responsible for the remainder are unknown.

In vivo dilatation of the postnatal ductus arteriosus by atrial natriuretic peptide in the rat.

Background: Alpha-human atrial natriuretic peptide (hANP) reportedly increases in premature infants with patent ductus arteriosus (PDA).

Objectives: To clarify a possible hANP effect to reopen the postnatal ductus, we studied in vivo reopening of the postnatal DA by a recombinant hANP, carperitide, in rats.

Methods: Near-term rat pups were incubated at 33 degrees C following caesarean section.

Constriction of the ductus arteriosus by selective inhibition of cyclooxygenase-1 and -2 in near-term and preterm fetal rats.

We studied the transplacental ductal constrictive effects of a selective cyclooxygenase (COX)-1 inhibitor (SC560), six selective COX-2 inhibitors including rofecoxib, and a non-selective COX inhibitor (indomethacin). Each drug was administered to the pregnant rats, and fetal ductus arteriosus (DA) was studied with a whole-body freezing method. The inner diameter ratio of the DA to the main pulmonary artery (DA/PA) was 1.

ACE inhibitors in pediatric patients with heart failure.

This article reviews reports of ACE inhibitor use in pediatric heart failure and summarizes the present implications for clinical practice. Captopril, enalapril, and cilazapril are orally active ACE inhibitors, and widely used in pediatric cardiology, although more than ten other ACE inhibitors have been applied clinically in adults. Effects of ACE inhibitors on the renin-angiotensin-aldosterone system in pediatric patients are similar to those in adults.

In vivo dilatation of the fetal and postnatal ductus arteriosus by inhibition of phosphodiesterase 3 in rats.

Background: Clinically, it appears that phosphodiesterase 3 (PDE 3) inhibitors, which are used for acute cardiac failure in premature infants, dilate the ductus arteriosus (DA).

Objectives: To clarify the ductus-dilating effects of PDE 3 inhibitors in near-term rat pups and their differential effects in near-term and preterm fetal rats, in in vivo studies.

Methods: The in vivo ductal diameter of rat pups and fetuses was measured using a rapid whole-body freezing method, by cutting on a freezing microtome and measuring with a microscope and micrometer.

In vivo reopening of the neonatal ductus arteriosus by a prostanoid EP4-receptor agonist in the rat.

Prostaglandin E1 is used to reopen the constricted ductus arteriosus in neonates with ductus-dependent circulation. To clarify possible prostanoid receptor agonists that can reopen the neonatal ductus with fewer side effects, we studied in vivo reopening of the neonatal ductus arteriosus by AE1-329, a prostanoid EP4-receptor agonist, in the rat. Neonatal rats were incubated at 33 degrees C.

In vivo constriction of the fetal and neonatal ductus arteriosus by a prostanoid EP4-receptor antagonist in rats.

Indomethacin is used to constrict the patent ductus arteriosus in premature infants. To clarify possible prostanoid receptor antagonists that can constrict the ductus, we studied in vivo constriction of the fetal and neonatal ductus arteriosus by AE3-208, a prostanoid EP4-receptor antagonist, in rats. Following quick cesarean section of near-term pregnant rats (21 d), neonates were incubated in room air at 33 degrees C.

Effect of decreased umbilical blood flow and hemorrhage, and decreased prostaglandins on the ductus venosus diameter in the rat.

Background: The closing mechanisms of the ductus venosus (DV) have not yet been revealed.

Objectives: The aims of this study were to document the perinatal closing process of the DV, to study the suppression of prostaglandins by indomethacin, and to determine the effects of umbilical blood flow to the fetal DV.

Methods: The proximal and distal DV diameters were studied in near-term fetal and neonatal rats with the rapid whole-body freezing method.

In vivo dilation of fetal and neonatal ductus arteriosus by inhibition of phosphodiesterase-5 in rats.

A recent in vitro study showed that sildenafil, a type 5 phosphodiesterase inhibitor, dilated the constricted ductus arteriosus of neonatal rabbits. We studied the in vivo ductus-dilating effects of sildenafil in fetal and neonatal rats. Ductus diameters were measured with whole-body freezing and cutting on a freezing microtome.

Increased constriction of the ductus arteriosus by dexamethasone, indomethacin, and rofecoxib in fetal rats.

Background: To find a better treatment for patent ductus arteriosus (PDA) in premature infants, the present study investigated the synergism of clinical doses of dexamethasone, indomethacin, and rofecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on the fetal ductus arteriosus (DA) in rats.

Methods And Results: Dexamethasone (0.3 mg/kg), indomethacin (0.

Ectopic expression of an embryonic skeletal myosin heavy chain in human fetal and Syrian hamster hearts.

The mammalian heart is known to contain only two isoformic myosin heavy chain (MHC) genes, alpha and beta. A previously uncharacterized MHC gene was isolated in Syrian hamster hearts (McCully et al., JMol Biol 1991).

Role of TBX1 in human del22q11.2 syndrome.

Background: Del22q11.2 syndrome is the most frequent known chromosomal microdeletion syndrome, with an incidence of 1 in 4000-5000 livebirths. It is characterised by a 3-Mb deletion on chromosome 22q11.

Thrombocytopenia in patients with 22q11.2 deletion syndrome and its association with glycoprotein Ib-beta.

Purpose: To elucidate whether thrombocytopenia in 22q11.2 deletion syndrome patients is associated with the hemizygosity of glycoprotein Ib-beta and to clarify the correlation of phenotype and genotype of this gene in 22q11.2 deletion syndrome patients with thrombocytopenia.

Growth of stenotic lesions after balloon angioplasty for pulmonary artery stenosis after arterial switch operation.

Little is known about the growth potential of pulmonary stenotic lesions after balloon angioplasty (BA) in patients after the arterial switch operation. The aim of this study was to evaluate the growth potential of pulmonary stenotic lesions after BA and assess the midterm results of BA for pulmonary artery stenosis after the arterial switch operation. Thirty-seven patients who had undergone 52 procedures had repeat catheterization at a median of 43 years (range 1.

Inhibition of in vivo constriction of fetal ductus arteriosus by endothelin receptor blockade in rats.

The fetal ductus can be constricted by drugs, including cyclooxygenase inhibitors (indomethacin), nitric oxide synthesis antagonists [N-nitro-L-arginine monomethyl ester (L-NAME)], and glucocorticoid hormones (dexamethasone). Constriction of the fetal ductus by endothelin (ET) 1 was reported in an in vitro study. We studied the preventive effect of a dual ET receptor antagonist (bosentan) and a selective ET-A blocker (CI-1020) on pharmacologic fetal ductal constriction in rats.