Changes in hormone sensitivity of pituitary mammotropes during progression from normal to autonomous.

نویسندگان

  • K H CLIFTON
  • J FURTH
چکیده

The autonomous mammotropie tumors (3I tT) studied have retained responsiveness to estrogen. Optimal growth of such tumors occurs at doses one-tenth tha t necessary to induce tumorous proliferation of mammotropie cells (Sit) in p i tu i ta ry glands in situ or in grafts or normal t)i tuitary tissue beneath the kidney capsule. The similari ty in sensitivity between normal 3 I t in situ and M:t in subeapsular grafts of normal p i tu i tary tissue indicates tha t immediate circulatory connection with the hypothalaInus does not play a dominant role in the effects of estrogen on the 3ft . The estrogen sensitivity of grafts of dependent 5~[tT is similar to tha t of normal X[t or intermediate between autonomous and normal Mt . These results suggest tha t gain in estrogen sensitivity may be an adapt ive phenomenon acquired gradually and is not an exclusive characteristic of autonomous cells. Additional results indicate tha t the subcapsular site is superior to both intramusenlar and subcutaneous graft sites for such studies.

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عنوان ژورنال:
  • Cancer research

دوره 21  شماره 

صفحات  -

تاریخ انتشار 1961