it appears thus that modulation of pituitary responsiveness to the action of grf is mediated by at least two independent mechanisms in the rat : in addition to the inhibitory action imposed by hypothalamic srif , which induces periods of refractoriness to the action of grf , it was shown in this study that in the pituitary level each grf stimulation also induces a transient desensitization of somatotrophs for about 1 h .
C0020663
hypothalamic
C0037659
srif