Effects of pituitary graft and 2-bromo-alpha-ergocryptine on mammary DNA synthesis in mice in relation to mammary tumorigenesis.
3H-thymidine incorporation into mammary DNA as an index of mammary DNA synthesis in C3H/He virgin females was significantly higher at proestrus than at estrus and diestrus. The rise in incorporation at proestrus was completely blocked by the administration of 2-bromo-alpha-ergocryptine (Bromocriptin) 1 day before proestrus. The incorporation was maintained at a higher level than that at proestrus by pituitary grafts. The results supported the view that mammary DNA synthesis, which is stimulated by prolactin, is an important factor for mammary tumorigenesis.
D000818:Animals; D001971:Bromocriptine / Q000494:pharmacology*; D004247:DNA / Q000096:biosynthesis*; D004873:Ergolines / Q000494:pharmacology*; D004971:Estrus; D005260:Female; D008321:Mammary Glands, Animal / Q000378:metabolism*; D008325:Mammary Neoplasms, Experimental / Q000209:etiology*; D051379:Mice; D008809:Mice, Inbred C3H; D010902:Pituitary Gland / Q000502:physiology*; D010903:Pituitary Gland, Anterior / Q000502:physiology* / Q000637:transplantation; D011247:Pregnancy; D011388:Prolactin / Q000502:physiology; D014185:Transplantation, Isogeneic
D004873:Ergolines; D001971:Bromocriptine; D011388:Prolactin; D004247:DNA