23 Result(s)
within
Kazuo Momma
English
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Chapter and Conference Paper
Dilatation of the Ductus Arteriosus by Diazoxide in Fetal and Neonatal Rats
We previously reported that ATP-sensitive potassium (KATP) channels regulate ductal constriction in response to oxygen [1]. Diazoxide is a KATP channel opener while the usefulness of diazoxide for hyperinsulinemi...
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Chapter and Conference Paper
Constriction of the Ductus Arteriosus with KATP Channel Inhibitors
The cause of fetal death by sulfonylureas (SUs), used for diabetes in pregnancy in the early 1960s, remained unsolved for decades. In 1993, Nakanishi discovered constriction of ductus arteriosus (DA) strips in...
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Chapter
Fetal and Neonatal Ductus Arteriosus Is Regulated with ATP-Sensitive Potassium Channel
The fetal patency and neonatal closure of the ductus arteriosus (DA) are regulated with oxygen and prostaglandins. The proposed oxygen sensors of fetal and neonatal DA include P450-endothelin and the Kv channe...
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Article
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 ...
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Article
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...
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Article
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...
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Article
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 (de...
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Article
The Effect of Vitamin A on Contraction of the Ductus Arteriosus in Fetal Rat
Endogenous retinoic acid may play a role in inducing smooth muscle differentiation in the fetal ductus arteriosus. Maternal administration of retinoic acid may accelerate the process. This study was designed t...
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Article
The Role of Nitric Oxide in Dilating the Fetal Ductus Arteriosus in Rats
Prostaglandin E is a major dilator of the fetal ductus arteriosus (DA), but the role of nitric in fetal ductal dilation has not been established. We studied the effects of a potent nitric oxide synthase inhibi...
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Article
Accelerated Maturation of Fetal Ductus Arteriosus by Maternally Administered Vitamin A in Rats
Maturation of fetal ductus arteriosus is associated with increased constriction in response to maternally administered indomethacin. Recently retinoic acid has been shown to be important in development of the ...
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Article
Developmental Changes in the Effect of Acidosis on Contraction, Intracellular pH, and Calcium in the Rabbit Mesenteric Small Artery
The purpose of the present study was to determine developmental changes in the effect of respiratory acidosis on vascular smooth muscle contraction. Vessel diameter, intracellular pH (pHi), and calcium concentrat...
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Article
Developmental Changes in the Contractile System of the Mesenteric Small Artery of Rabbit
This study investigated developmental changes in the contractile system of the mesenteric small arteries of the rabbit. Arteries about 1 mm in length and 100-250 μm in internal diameter were dissected out from...
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Article
In Situ Morphology of the Aorta and Common Iliac Artery in the Fetal and Neonatal Rat
ABSTRACT: In situ cross-sectional morphology of the ascending, descending, and abdominal aorta and the common iliac arteries was studied after rapid, whole-body freezing of fetal and neonatal rats. In the fetus, ...
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Article
In Situ Morphology of the Foramen Ovale in the Fetal and Neonatal Rat
ABSTRACT: In situ cross-sectional morphology of the foramen ovale was studied after rapid whole-body freezing of the fetal and neonatal rat. In the fetus, the foramen ovale was open widely toward the left atrium ...
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Article
In Situ Morphology of the Ductus Venosus and Related Vessels in the Fetal and Neonatal Rat
ABSTRACT: In situ cross-sectional morphology of the ductus venosus and related vessels was studied after rapid whole-body freezing of the fetal and neonatal rat. In the fetus, the ductus venosus was open widely, ...
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Article
Fetal Cardiovascular Effects of Nifedipine in Rats
ABSTRACT: In this study we clarify the fetal cardiovascular effects of nifedipine. Nifedipine was administered to near-term rats and cardiovascular morphology of the fetus was studied with a rapid whole-body f...
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Article
Increased Constriction of the Ductus Arteriosus with Combined Administration of Indomethacin and Betamethasone in Fetal Rats
ABSTRACT: To find a better treatment for patent ductus arteriosus of preterm infants, we studied the combined effect of indomethacin and betamethasone on the fetal ductus in rats. We used a rapid whole-body fr...
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Article
In Situ Morphology of the Heart and Great Vessels in Fetal and Newborn Rats
ABSTRACT. Morphology of the cardiac chambers and great vessels of fetal and neonatal rats was studied using the whole body freezing technique and by sectioning through the short axis of the heart with a freezi...
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Article
In Vivo Constriction of the Ductus Arteriosus by Nonsteroidal Antiinflammatory Drugs in Near-Term and Preterm Fetal Rats
ABSTRACT. Herein we report age differences of in vivo constriction of the fetal ductus arteriosus by nonsteroidal antiinflammatory drugs in near-term and preterm rats. Two potent nonsteroidal antiinflammatory dru...
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Article
Characteristic Morphology of the Constricted Fetal Ductus Arteriosus following Maternal Administration of Indomethacin
ABSTRACT: Indomethacin 10 mg/kg was administered to the maternal rat on the 21st day of pregnancy, and the fetal and neonatal ductus arteriosus were studied using the rapid whole-body freezing technique. The s...
