Somatostatin-28 is an hormonally active peptide secreted into hypophysial portal vessel blood

@article{Millar1983Somatostatin28IA,
  title={Somatostatin-28 is an hormonally active peptide secreted into hypophysial portal vessel blood},
  author={Robert Peter Millar and William Sheward and Ivonne Wegener and George Fink},
  journal={Brain Research},
  year={1983},
  volume={260},
  pages={334-337}
}
Somatostatin 14 and 28 (SS-14 and SS-28) have been measured in hypophysial portal blood of male Wistar rats. The concentration and total amount of SS released into portal blood were increased 6- to 7-fold by electrical stimulation of the median eminence. On HPLC, only two peaks of immunoreactivity were detected in extracts of portal plasma and these peaks corresponded with SS-14 and SS-28, respectively. The amount of SS-28 in portal plasma was, on a molar basis, similar or greater than that of… Expand
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Findings suggest that, in contrast to S-14, S-28 is a hormone and may modulate postprandial nutrient absorption and use. Expand
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The primary structure of this intestinal peptide has been found to be an octacosapeptide, somatostatin-28, which is a precursor of somatogtatin-14 and Sequence comparison between somatstatin- 28 and prohormones also suggest that it may be a precursor. Expand
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  • Biology, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 1980
TLDR
An octacosapeptide that is most likely a precursor (pro-hormone) of somatostatin in the hypothalamus has been isolated from acid extracts of porcine hypothalami and found to have the amino acid sequence Ser-Ala-Asn-Ser- asn-Pro- Ala-Met-AlA-Pro, which crossreacts strongly with antisera generated against the som atostatin tetradecapeptide. Expand
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