The immunohistochemical detection of the thymidine analog, 5-bromo-2'-deoxyuridine (BrdU) is shown to be a useful and reliable method to positively identify fetal brain transplants in standard histological preparations. This technique offers several advantages over the [3H]thymidine autoradiographic method, including being much more rapid and avoiding the use of radionuclides.

Variations in the treatment conditions which affect the frequency of BUdR-induced morphogenic lesions in Drosophila melanogaster have been studied. By varying the concentrations of BUdR and FU, or by changing the duration of treatment, it has been demonstrated that increased incorporation of BUdR into DNA results in a concomitant increase in morphogenic lesions. A quantitative analysis of the d...

Astrocytes in primary culture can be classified morphologically into two types: fibrous astrocytes and protoplasmic astrocytes. To examine the role of tenascin-C (TN) in an in vitro astrocyte culture, primary cultures of astrocytes prepared from the brains of wild-type and of TN-deficient embryonic mice were analyzed. In primary culture of astrocytes from TN-deficient mice fibrous astrocytes di...

On a chemically defined growth medium the degree of substitution of thymidine with 5-bromodeoxyuridine (BUdR) in DNA of Tetrahymena pyriformis was controlled by the concentration of tetrahydrofiolic acid, BUdR and thymidine in the medium. A correlation between the degree of BUdR substitution in DNA and the reduction in rate of total RNA synthesis has been established. It was found that the redu...

The thymidine analog 5-bromodeoxyuridine (BrUdR) incorporated into DNA has been successfully used as a selective agent (1, 2) or mutagen (3) on various animal cells. Some of its effects are understandable in terms of base substitution in the genetic material; others, however, such as the reversible suppression of cytodifferentiation (4-7), remain unexplained. We have examined the effects of pro...