Biomaterial Database

N-ethyl-N-nitrosourea-induced teratogenesis of brain in the rat. A cellular and cytoarchitectural analysis of the neocortex. 1978

B H Hallas, and G D Das

N-Ethyl-N-nitrosourea (ENU) was administered intravenously to pregnant Wistar-albino rats on days 14--21 of gestation in order to study the teratological effects of the carcinogen on the developing brain. Offspring were killed 60 days postnatally, and the brains examined histologically by cresyl violet staining and Golgi-Cox preparations. Macroscopic examination of the brains revealed a graded pattern of microcephaly. Injection of ENU on day 14 of gestation gave the most severe effects and injection on day 21 the least effects. Microscopic examination of the neocortex revealed a graded reduction in the lateral and sagittal lengths, thickness, and the number of cells in a sample slab of the cortex. In the Golgi-Cox preparations the pyramidal neurons of cortical layers III and V, as well as neurons of other layers, were seen to have fewer secondary and tertiary dendrites, and the length of their dendrites appeared stunted. These characteristics also were graded in relation to the day of injection of ENU. Altered cytology and cytoarchitecture of the neocortex and possible underlying mechanisms are discussed.

UI	MeSH Term	Description	Entries
D008831	Microcephaly	A congenital abnormality in which the CEREBRUM is underdeveloped, the fontanels close prematurely, and, as a result, the head is small. (Desk Reference for Neuroscience, 2nd ed.)	Microlissencephaly,Severe Congenital Microcephaly,Congenital Microcephalies, Severe,Congenital Microcephaly, Severe,Microcephalies,Microcephalies, Severe Congenital,Microcephaly, Severe Congenital,Microlissencephalies,Severe Congenital Microcephalies
D009607	Nitrosourea Compounds	A class of compounds in which the core molecule is R-NO, where R is UREA.	Compounds, Nitrosourea
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D005038	Ethylnitrosourea	A nitrosourea compound with alkylating, carcinogenic, and mutagenic properties.	Nitrosoethylurea,N-Ethyl-N-nitrosourea,N Ethyl N nitrosourea
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013723	Teratogens	An agent that causes the production of physical defects in the developing embryo.	Embryotoxins,Fetotoxins,Teratogen
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus