1975•PubMedRequires access
Inhibitory effect of actinomycin D on the inductio of rat mammary tumors by in vitro exposure to 7,12-dimethylbenz(a)anthracene.
Takeshi Tominaga, Noriyuki Tei, T Taguchi, Yoshifumi Takeda
Open publisher page 3 citations
Abstract
The inhibitory effect of actinomycin D on the induction of tumors by in vitro exposure of mammary glands to 7,12-dimethylbenz(a)anthracene was studied. When actinomycin D was given i.p. 24 hr before excision of the mammary glands, the induction of tumors by in vitro exposure of the glands to 7,12-dimethylbenz(a)anthracene was significantly decreased. On the other hand, when actinomycin D was administered 24 hr after excision, it had no effect on the induction of tumors. In vitro exposure of excised glands to 7,12-dimethylbenz(a)anthracene and actinomycin D significant decreased tumor induction. However, the order of exposure to 7,12-dimethylbenz(a)anthracene and actinomycin D influenced the inhibitory effect of actinomycin D on tumor induction. Results indicated that this might be due to a difference in the amounts of 7,12-dimethylbenz(a)anthracene and actinomycin D bound to the mammary glands.