ABSTRACT
Anterior pituitary cells have been shown, by immunocytochemistry, to contain neurotensin. In fact, considerable evidence has accumulated to indicate that the peptide can alter the release of most anterior pituitary hormones by hypothalamic and/or direct pituitary effects. In the experiments with the intraventricular injection of neurotensin antiserum, it was found that the antiserum lowered growth hormone in ovariectomized females, ovariectomized estrogen progesterone-primed females and also male rats. Surprisingly, the intravenous injection of the antiserum produced the opposite effect and an elevation in growth hormone levels in both types of ovariectomized rats. Since the hormone persists in the gland following pituitary stalk section, it not only reaches the pituitary via the portal vessels but actually may be synthesized within pituitary cells. The lack of physiological significance of neurotensin at the pituitary level in the male is also supported by the failure of the antiserum to alter prolactin release from dispersed anterior pituitary cells of males.
