Abstract
The effects of dermorphin, a new potent opioid peptide, on structural and ultrastructural changes in the crop sac and in pituitary lactotrophs were assessed in pigeons ( Columba livia). A single administration of dermorphin into the third cerebral ventricle (1 μg) and the same dose repeated for 3 consecutive days both produced maximal crop sac stimulation, as documented by the presence of milk-like material as well as by scanning and transmission electron microscopy of crop sac mucosa. In addition, marked stimulatory effects were also observed in pituitary lactotrophs, as shown by stimulation of Golgi apparatus, enlargement of rough endoplasmic reticulum, increase in mitochondria size, and the presence of lysosomes and electron-opaque granules. The stimulatory effects of dermorphin on the crop sac and lactotrophs were completely prevented by naloxone, an antagonist at opiate receptors. Since dermorphin is a natural constituent of the avian brain, it has been suggested that this peptide may represent the still-obscure hypothalamic prolactin stimulatory factor.
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.
