Depolarization- and ionophore-induced release of octacosa somatostatin from stalk median eminence synaptosomes.
Species of somatostatin of higher molecular weight were present in the nerve terminals (synaptosomes) of ovine stalk median eminences and were released by depolarizing stimuli. One of these species was identified as the biologically active molecule octacosa somatostatin. Octacosa somatostatin appears therefore to be secreted into the hypothalamic-hypophyseal system, supporting the concept of a role for this peptide in regulating pituitary hormone secretion.
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D007476:Ionophores / Q000494:pharmacology; D008473:Median Eminence / Q000378:metabolism*; D008564:Membrane Potentials; D008970:Molecular Weight; D011498:Protein Precursors / Q000378:metabolism; D011863:Radioimmunoassay; D012636:Secretory Rate / Q000187:drug effects; D012756:Sheep; D013004:Somatostatin / Q000378:metabolism*; D013574:Synaptosomes / Q000378:metabolism
D007476:Ionophores; D011498:Protein Precursors; D000001:Calcimycin; D013004:Somatostatin