Abstract
The classic postulate by Harris of neuroendocrine control of the anterior pituitary gland predicted that factors would be identified within the hypothalamus that were transported via capillaries of the hypophyseal-portal vessels to regulate pituitary hormone secretion. Two such factors have recently been identified that regulate growth hormone secretion — growth hormone releasing factor (GRF) (1) and the inhibitory peptide, somatostatin (SRIF) (2) (Fig 1). SRIF is widely synthesized and distributed through the hypothalamus and extra-hypothalamic brain (3). Somatostatinergic neurons that originate in perikarya in the periventricular nucleus of the hypothalamus have axons that project via the retrochiasmatic region to terminate in nerve endings in the external layer of the median eminence (4). Manipulation of growth hormone and steroid hormone homeostasis influence preprosomatostatin mRNA (5,6) and SRIF content (7) primarily in this pathway and lesions along the pathway deplete the median eminence of SRIF (8). It thus appears likely that this tract represents the hypophysiotropic somatostatinergic pathway.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
