Abstract

The uptake of intraperitoneally injected 125I-labeled rat growth hormone into brain and peripheral tissues was measured in normal and hypophysectomized adult rats. A significant level of radioactivity was observed in the seven brain regions examined -- the telencephalon, diencephalon, midbrain, pons-medulla, cerebellum, pineal and pituitary glands. The pineal and pituitary glands, which are outside the blood-brain barrier, contained three to four times the concentration of radioactivity of the other brain regions. Compared to brain, the level of radioactivity was much higher in peripheral tissues (the diaphragm, kidney, serum and liver). For example, the serum contained ten times the level of radioactivity of most brain regions. For a given tissue, however, the normal and hypophysectomized rats showed a comparable amount of 125I-growth hormone. Trichloroacetic acid precipitates from each tissue sample showed that peripheral tissues had a higher proportion of radioactivity (35-48% of total tissue radioactivity) than the brain samples (13-26%). The data support the view that growth hormone, or a metabolite can enter the central nervous system and may directly affect on-going metabolic processes.

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 call

Disclaimer: 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.