Chick embryos have been used widely as model systems for studies in experimental embryology and teratology. Especially early chick embryos are very useful for studies of neural tube defects. Local anesthetics such as lidocaine, tetracaine and ketamine are known to inhibit the formation of microfilaments and cause neural tube defects. We made a try to figure out the effect of local anesthetics on neurulation in early chick embryo, which is stage 8 by Hamburger & Hamiliton classification. After 6~9 hours incubation in media treated with above local anesthetics, we observed the effects of these agents by LM and EM. Stage 8 chick embryos responded to local anesthetics in a dose related manner. Tetracaine showed most potent effects. Neural folds failed to make a contact, so the neural tube was left open. In high dosage, the case of no growth or little growth of embryo was also observed. On scanning electron microscopic examination, the surface of neuroepithelium was flattened in embryos treated with ketamines. On transmission electron microscopic examination. neuroepithelium of embryos cultured in ketamine showed the decrease of microfilaments and less conspicuous feature of mitochondria and rough ER(endoplasmic reticulum)'s.
Actin Cytoskeleton ; Anesthetics, Local* ; Animals ; Chick Embryo* ; Classification ; Embryology ; Embryonic Structures ; Ketamine ; Lidocaine ; Microscopy, Electron ; Mitochondria ; Neural Crest ; Neural Tube ; Neural Tube Defects ; Neurulation* ; Teratology ; Tetracaine

Chick embryos have been used widely as model systems for studies in experimental embryology and teratology. Especially early chick embryos are very useful for studies of neural tube defects. We made a try to figure out the effect of Ca++ on neurulation using Ca++ antagonist and Ca++ free media in early chick embryo, which is stage 8 by Hamburger & Hamilton classification. After 6~9 hours incubation in media treated with verapamil and media without Ca++, we observed the effects of these agents by LM and EM. All of 12 embryos incubated in Ca++ free media showed that neural tube was diffusely opened along the whole axis and other deformity was not found. The chick embryos cultured in medium treated with verapamil revealed various abnormalities in dose related manner. The case of arrest of the growth was also observed, which was not found Ca++ free media group. On scanning electron microscopic examination, the surface of neuroepithelium was flattened in embryos cultured in Ca++ free media.
Animals ; Axis, Cervical Vertebra ; Chick Embryo* ; Classification ; Congenital Abnormalities ; Embryology ; Embryonic Structures ; Microscopy, Electron, Scanning ; Neural Tube ; Neural Tube Defects ; Neurulation* ; Teratology ; Verapamil

The anxiety of pregnant women who are receiving drug therapy is mainly caused by their misperception of the safety and risks of medications. In developed countries, teratology information services successfully provide pregnant women and their health-care providers with evidence-based teratogen information. In our country, the Korean Motherisk Program started to provide prenatal teratogen-risk counseling approximately 10 years ago first to women referred to the clinic, later by e-mail, and more recently over the telephone. The Program has also established international collaborations which propelled its capability to gain experience and obtain information on the safe use of medications in pregnancy. Since 2010, we have a unique opportunity to reduce the gap on teratogen information across our country and among medical providers including physicians, pharmacists and nurses through the Mother Safe Program supported by the Ministry for Health and Welfare. Similar to what is occurring in other developed countries, this program intends to provide pregnant women and their health-care providers with evidence-based information on their medications in order to reduce unnecessary pregnancy terminations and decrease their anxiety on the potential risks of medications prescribed during pregnancy.
Anxiety ; Cooperative Behavior ; Counseling ; Developed Countries ; Electronic Mail ; Female ; Humans ; Information Services ; Mothers ; Pharmacists ; Pregnancy ; Pregnant Women ; Prenatal Care ; Telephone ; Teratogens ; Teratology

BACKGROUND AND PURPOSE: Neurobehavioral teratology is a term used for the postnatal effects on behavior of prenatal exposure to drug or to specific environment. Perinatal hypoxia is a major risk factor for development of behavioral abnormalities, such as cerebral palsy, mental retardation and learning disability. The objective of this study is to investigate the effects of neonatal hypoxia on long-term changes of behavior and neurochemical system and to learn the role of 5-hyroxytryptamine(5-HT) in hypoxic stress. METHODS: Sprague-Dawley rats were grouped by hypoxia and/or 5-HT receptor antagonist treatment. Exposure to 100% N2 gas was done in postnatal day(PND) 2 for 12 minutes. NAN-190 HBr or ketanserin tartrate or both were injected intraperitoneally 30 minutes before exposure to hypoxic environment. Rats were weighed periodically and examined the eye opening. Wire maneuver test was done on PND 22. Between PND 40-55 and PND 63-84, explorative behavior test and Rota-Rod test were done serially. They were sacrificed in PND 100, and aminergic neurotransimitters and their metabolites were measured by High Performance Liquid Chromatography - Electrochemical Detection(HPLC ECD) system. Receptor binding assay was done using 8-OH-DPAT and ketanserin HCl in brain cortex. RESULTS: The group treated with 5-HT receptor antagonist and hypoxia showed higher death rate than 5-HT receptor antagonist or hypoxia alone. There were no differences in weight gain, eye opening, and the result of wire maneuver test among each groups. In explorative behavior test, NAN+N2 group in male and NAN group in female showed markedly increased activities. In Rota-Rod test, NAN and NAN+N2 groups in both male and female showed decreased motor coordination. There were no differences in the concentration of aminergic neurotransmitters and their metabolites, when measured in PND 100 according to the brain sites. There were no differences in pKd of 5-HT receptors measured on PND 100. But Bmax of 5-HT1A receptor were low in N2, NAN and NAN+N2 groups. NAN and NAN+N2 groups showed elevated Bmax of 5-HT2A/2C receptor. CONCLUSION: Exposure to hypoxia in neonatal period causes long-lasting neurobehavioral changes with neurochemical abnormalities, and 5-HT receptor activity has a role in that mechanism.
8-Hydroxy-2-(di-n-propylamino)tetralin ; Animals ; Anoxia ; Brain ; Cerebral Palsy ; Chromatography, Liquid ; Female ; Humans ; Infant, Newborn* ; Intellectual Disability ; Ketanserin ; Learning Disorders ; Male ; Mortality ; Neurotransmitter Agents ; Rats* ; Rats, Sprague-Dawley ; Receptor, Serotonin, 5-HT1A ; Receptors, Serotonin ; Risk Factors ; Serotonin ; Teratology* ; Weight Gain