Animals ; Brain ; embryology ; Ear ; embryology ; Esophagus ; embryology ; Fallopian Tubes ; embryology ; Female ; Heart ; embryology ; Humans ; Kidney ; embryology ; Liver ; embryology ; Lung ; embryology ; Male ; Organogenesis ; physiology ; Penis ; embryology ; Rabbits ; Stomach ; embryology ; Vagina ; embryology

OBJECTIVEConotruncal defects (CTD) is a common type of cyanotic congenital heart defects. It was shown that CTD might be produced by ablation of cardiac neural crest during early stage embryos in experimental studies. There were many kinds of genes involved and cardiac alpha-actin (CAA) was one of them. The purpose of this study was to investigate the spatial expression of CAA gene during embryonic heart development, and to explore its role in the pathogenesis of congenital heart defects.

METHODSExperimental chicken embryos were subjected to cardiac neural crest ablation by using electric stimulation at 36-40 hr incubation stage. The embryos and organs of experimental and normal control groups during different developing periods were taken out, RNA was extracted by Trizol, and then reverse transcription was done. The dynamic changes of CAA mRNA expression at different development stages of embryos were assayed by fluorescent real-time PCR. The embryos and tissues at different stages were taken out, and paraffin sections were made. The localizations of CAA antibody expression in the developmental embryos were detected by immunohistochemical analysis (peroxidase-DAB coloration).

RESULTS(1) The expression of CAA gene was detected at early embryo development, and increased subsequently to a stable level. Its expression was mainly limited to heart site, and could be increased along with the maturation of the cardiac muscle. There was no expression or little trace expression in liver, brain, and stomach. (2) There was a significantly low level of CAA gene expression on days 2-7 of chicken embryos whose cardiac neural crest were ablated in comparison with normal controls (P = 0.013). The level of CAA gene expression was also down-regulated on days 7, 9 and 15 of embryonic cardiac tissues (P = 0.029).

CONCLUSIONCAA gene is closely associated with heart development, its expression was adjusted by cardiac neural crest, and its dysfunction may be an important factor leading to congenital heart defects.

Actins ; genetics ; metabolism ; Animals ; Chick Embryo ; Gene Expression Regulation, Developmental ; Heart ; embryology ; Heart Defects, Congenital ; embryology ; Neural Crest ; embryology

BackgroundOutflow tract (OFT) septation defects are a common cause of congenital heart disease. Numerous studies have focused on the septation mechanism of the OFT, but have reported inconsistent conclusions. This study, therefore, aimed to investigate the septation of the aortic sac and the OFT in the early embryonic human heart.

MethodsSerial sections of 27 human embryonic hearts from Carnegie stage (CS) 10 to CS19 were immunohistochemically stained with antibodies against α-smooth muscle actin (α-SMA) and myosin heavy chain.

ResultsAt CS10-CS11, the OFT wall was an exclusively myocardial structure that was continuous with the aortic sac at the margin of the pericardial cavity. From CS13 onward, the OFT was divided into nonmyocardial and myocardial portions. The cushion formed gradually, and its distal border with the OFT myocardium was consistently maintained. The aortic sac between the fourth and sixth aortic arch arteries was degenerated. At CS16, the α-SMA-positive aortopulmonary septum formed and fused with the two OFT cushions, thus septating the nonmyocardial portion of the OFT into two arteries. At this stage, the cushions were not fused. At CS19, the bilateral cushions were fused to septate the myocardial portion of the OFT.

ConclusionsData suggest that the OFT cushion is formed before the aortopulmonary septum is formed. Thus, the OFT cushion is not derived from the aortopulmonary septum. In addition, the nonmyocardial part of the OFT is septated into the aorta and pulmonary trunk by the aortopulmonary septum, while the main part of the cushion fuses and septates the myocardial portion of the OFT.

Actins ; metabolism ; Alkaline Phosphatase ; metabolism ; Aorta ; embryology ; Heart ; embryology ; Heart Valves ; embryology ; Humans ; Immunohistochemistry ; Myosin Heavy Chains ; metabolism

To investigate the expression of phospholipase C-gamma1 (PLC-gamma1) in mouse embryonic tissues, serial tissue sections were prepared routinely for immunocytochemistry for PLC-gamma1. The results showed that PLC-gamma1 was expressed in the cartilage, skeletal muscles, myocardium, the collecting tubule of the kidney, connective tissues and the brain, suggesting the important role PLC-gamma1 and the related signal pathway may play in the development of mouse embryonic tissues.
Animals ; Brain ; embryology ; enzymology ; Cartilage ; embryology ; enzymology ; Embryo, Mammalian ; enzymology ; Female ; Fetal Heart ; enzymology ; Immunohistochemistry ; Kidney ; embryology ; enzymology ; Mice ; Muscle, Skeletal ; embryology ; enzymology ; Phospholipase C gamma ; biosynthesis ; Pregnancy

The development of heart is an accurate, coordinated process including primordial cardiac cell differentiation, migration, and multi-cell combination. This process is accompanied by cell apoptosis, and by a series of gene regulation. If gene gets out of regulation, abnormal cell apoptosis will occur, which will lead to abnormal development of embryonic heart, or even malformation. By studying gene expression on apoptosis, we investigated the relationship between apoptosis and embryonic heart development, clarified the relevant mechanism for the clinical diagnosis and treatment of heart diseases.
Apoptosis ; genetics ; Gene Expression Regulation, Developmental ; Heart ; embryology ; Humans

OBJECTIVETo explore the essential features of the potential distribution of electrocardiac field.

METHODSThe ECGs of 60 hearts of 5-day chick embryos were immersed in normal saline solution or distilled water and their different conductivities were recorded at 5 points at different distances in 4 directions perpendicular to each other. Comparison of the form and amplitude of ECGs was made between every two points with the same distance to the heart in 2 opposite directions to determine the potential distribution of the electrocardiac field of the one-chambered heart.

RESULTSThe ECGs recorded at every 2 points in 2 opposite directions with the same distance to the heart immersed in the same liquid medium were both upper standing, with no significant different between their amplitude of R(r) wave (P > 0.05).

CONCLUSIONThe uniform outward potential distribution of the electrocardiac field might not represent the form of depolarization but that of sphere-like and single-source when the influence of different reference points and thickness of different chamber walls upon mapping of body surface is excluded.

Action Potentials ; Animals ; Chick Embryo ; Electrocardiography ; Heart ; embryology ; In Vitro Techniques

Isolated absence of the ductus arteriosus is extremely rare condition although the ductus arteriosus may be hypoplastic or aplastic in association with other aortic arch anomalies. Authors described a case of isolated agenesis of the ductus arteriosus documented by postmortem examination of a newborn infant who died of pneumonia following operation for a large omphalocele. The heart showed ventricular septal defect. However, no other cardiovascular anomalies were associated in this case. There were three vessels that were taking off from the aorta consisted of the right brachiocephalic artery, left common carotid-artery and left subclavian artery. The anteriorly located pulmonary artery was divided into the right and left pulmonary arteries. There was no connection of vessel between the pulmonary artery and the aorta.
Abnormalities, Multiple/embryology/pathology ; Ductus Arteriosus/*abnormalities ; Heart Defects, Congenital/embryology/pathology ; Hernia, Umbilical/complications ; Humans ; Infant, Newborn ; Male

Animals ; Chick Embryo ; physiology ; Electrocardiography ; methods ; Heart ; embryology ; physiology ; Heart Rate ; physiology

AIMTo investigate the expression of androgen receptors in the extragenital tissues of developing human embryo.

METHODSUsing immunohistochemistry, we investigated the distribution of androgen receptor (AR) in the extragenital tissues of paraffin-embedded tissue sections of first trimester (8-12 weeks gestation) human embryos. Gender was determined by polymerized chain reaction.

RESULTSThere were no differences in the expression and distribution of AR in male and female embryos at any stage of gestation. AR expression was seen in the thymus gland. The bronchial epithelium of the lungs showed intense positive staining with surrounding stroma negative. Furthermore, positive staining for androgen receptor was exhibited in the spinal cord with a few positive cells in the surrounding tissues. Cardiac valves also showed strong positive staining but with faint reactivity of the surrounding cardiac muscle. There was no staining in kidney, adrenal, liver or bowel.

CONCLUSIONThis study demonstrates that immunoreactive AR protein is present in a wide variety of human first trimester fetal tissues and shows the potential for androgen affecting tissues, which are mostly not considered to be androgen dependent. Moreover, it implies that androgen might act as a trophic factor and affect the early development of these organs rather than simply sexual differentiation.

Bronchi ; cytology ; embryology ; metabolism ; Female ; Fetus ; cytology ; metabolism ; Heart ; embryology ; Humans ; Immunohistochemistry ; methods ; Male ; Myocardium ; cytology ; metabolism ; Pregnancy ; Pregnancy Trimester, First ; Receptors, Androgen ; genetics ; metabolism ; Spinal Cord ; cytology ; embryology ; metabolism ; Thymus Gland ; cytology ; embryology ; metabolism

Anomalous aortic origin of the left subclavian artery (LSCA) from the left pulmonary artery (LPA) is a rare congenital cardiac malformation. We describe a case of LSCA from the LPA via ductus arteriosus in association with a double-outlet right ventricle, which never has been reported previously in Korea.
Double Outlet Right Ventricle* ; Ductus Arteriosus ; Embryology ; Heart Defects, Congenital ; Humans ; Korea ; Pulmonary Artery* ; Subclavian Artery*