The role of sensory feedback in the early ontogeny of motor coordination remains a topic of speculation and debate. On E20 of gestation (the 20th day after conception, 2 days before birth), rat fetuses can alter interlimb coordination after a period of training with an interlimb yoke, which constrains limb movement and promotes synchronized, conjugate movement of the yoked limbs. The aim of thi...

Sprague-Dawley rats were infected on day 20 of pregnancy by intraperitoneal inoculation with Neisseria gonorrhoeae. Disseminated gonococcal infection (DGI) and pelvic inflammatory disease (PID) strains in the presence of C1q but not in the presence of bovine serum albumin (BSA) were able to spread from the pregnant rat to the fetus and resulted in fetal mortality. Transmission of DGI and PID st...

Although fetal growth is generally considered to be independent of pituitary growth hormone (GH), it is possible that pituitary GH plays a modulatory role in organ development or that a GH-like substance of non pituitary origin may influence fetal growth through the GH receptor. Accordingly, we have used immunohistochemistry, northern blot analysis, the reverse transcriptase-polymerase chain re...

The prevention of neonatal rickets by oral supplementation with vitamin D2 (ergocalciferol) has tended to obscure our ignorance of the natural mechanism by which young mammals receive an adequate supply of vitamin D. To investigate the possibility of specific intrauterine transfer and storage of vitamin D in fetal tissues, vitamin D-deficient female rats were given depot injections of 3H- or 14...

The bearing of young by mammals is considered a normal biological process. Pregnancy once established, however, proceeds with little regard for the life of the mother. Indeed, marked disease states may be present and progressing without the production of abortion. In this respect, namely, that the fetus matures with little regard for the life of the mother, the growth of a fetus in a host is si...

The Smith-Lemli-Opitz syndrome-affected fetus presents a deficiency in delta7-dehydrocholesterol reductase, the last enzymatic step in the cholesterol biosynthesis pathway. Development of the abnormal human fetus takes place in a normal environment as the heterozygous mother's cholesterolemia remains normal. An animal model for this disease has been obtained from the offspring of pregnant rats ...