ACQUIRED RESISTANCE TO THE THYROID-STIMULATING AND PSEUDOLUTEINIZING HORMONE OF CATTLE ANTERIOR PITUITARY*

Abstract
When guinea pigs received continuous injections of thyroid stimulating hormone of cattle anterior pituitary for long periods, there occurred, for 4-6 weeks, thyroid stimulation with ovarian changes; this was followed by retrogression and return to normal. Continued administration with periodic interruptions was accompanied by hastened retrogression.