Primary structure and biological activity of hemoglobin-related hypothalamic peptides

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Measurement of Heme Synthesis Levels in Mammalian Cells
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A A Galoyan1

  • 1Institute of Biochemistry, NAS RA, Yerevan, Republic of Armenia.

Biopolymers
|January 1, 1997
PubMed

Insights

Researchers isolated novel hemorphin peptides from bovine hypothalamus that constrict coronary arteries by activating calmodulin-dependent enzymes. These findings reveal new hemoglobin-derived peptides with potential cardiovascular implications.

Area of Science:

  • Biochemistry
  • Cardiovascular Science
  • Neuroendocrinology

Background:

  • Hemoglobin-derived peptides, known as hemorphins, have diverse biological activities.
  • The bovine hypothalamus is a source of bioactive peptides.
  • Calmodulin-dependent enzymes play crucial roles in cellular signaling.

Purpose of the Study:

  • To isolate and characterize novel peptides from bovine hypothalamic extract with coronary constrictory activity.
  • To determine the relationship of these peptides to the known hemorphin group.
  • To investigate the mechanism of action involving calmodulin.

Main Methods:

  • Peptide isolation and sequencing from bovine hypothalamic extract.
  • Assay of coronary constrictory activity.
  • Calmodulin binding assays and activation of calmodulin-dependent enzymes.

Main Results:

  • Five individual fractions with coronary constrictory activity were isolated and sequenced.
  • All identified fractions belong to the hemorphin group of hemoglobin-derived peptides.
  • These hemorphins bind calmodulin and activate calmodulin-dependent enzymes.
  • New hemoglobin alpha- and beta-chain fragments with unknown activity were also identified.

Conclusions:

  • Novel hemorphins from the bovine hypothalamus exhibit coronary constrictory effects.
  • The mechanism involves calmodulin binding and activation of downstream enzymes.
  • These findings expand the known repertoire of hemorphins and their physiological roles.
  • Further research is warranted to explore the therapeutic potential of these peptides.

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