"Pituitary Gland"

The role of ascorbic acid in the biosynthesis of the neuroendocrine peptides alpha-MSH and TRH.

The characterization of the ascorbic acid-mediated alpha-amidation of alpha-melanotropin in cultured intermediate pituitary lobe cells.

Previous studies have shown that cultured rat intermediate pituitary lobe cells lose the ability to form ACTH-(1-13)NH2-related molecules (alpha MSH) and instead produce ACTH-(1-14)-related peptides. In vitro studies have shown that peptidylglycine …

Further characterization of the peptidyl alpha-amidating enzyme in rat anterior pituitary secretory granules.

In previous studies we have demonstrated a secretory granule-associated peptide alpha-amidation activity in rat anterior, intermediate, and posterior pituitary. This activity is capable of converting 125I-labeled synthetic D-Tyr-Val-Gly to labeled …

Acetylation of alpha MSH and beta-endorphin by rat neurointermediate pituitary secretory granule-associated acetyltransferase.

ACTH(1-8) and ACTH(9-13)NH2 were used as potential enzyme inhibitors to begin examining the relationship between the acetylation of ACTH- and beta-endorphin-related peptides. ACTH(1-8) was a potent inhibitor of the acetylation of both ACTH- and …

The alpha-amidation of alpha-melanocyte stimulating hormone in intermediate pituitary requires ascorbic acid.

Rat intermediate pituitary cells in primary culture display a time-dependent loss of the ability to produce COOH-terminally alpha-amidated alpha MSH (Glembotski, C.C., Eipper, B.A., and Mains, R.E. (1983) J. Biol. Chem. 258, 7299-7304). Instead of …

Characterization of a peptide alpha-amidation activity from rat anterior pituitary.

A secretory granule associated enzymatic activity from the rat anterior pituitary that can convert the synthetic peptide D-Tyr-Val-Gly into D-Tyr-Val-NH2 is described. Due to the presence of inhibitory activity in the cytosol and rough endoplasmic …

Peptide alpha-amidation activity in mouse anterior pituitary AtT-20 cell granules: properties and secretion.

Mouse anterior pituitary corticotropic tumor cells (AtT-20/D-16v) were homogenized and subjected to subcellular fractionation. A secretory granule associated enzyme activity was detected which could convert D-Tyr-Val-Gly into D-Tyr-Val-NH2. The …

Bovine intermediate pituitary alpha-amidation enzyme: preliminary characterization.

A secretory granule-associated enzymatic activity that converts mono-[125I]-D-Tyr-Val-Gly into mono-[125I]-D-Tyr-Val-NH2 has been studied. The activity is primarily soluble and shows optimal activity at pH 7 to pH 8. Amidation activity was stimulated …

Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid.

An enzymatic activity capable of producing an alpha-amidated peptide product from its glycine-extended precursor has been identified in secretory granules of rat anterior, intermediate, and neural pituitary and bovine intermediate pituitary. High …

Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid.

An enzymatic activity capable of producing an alpha-amidated peptide product from its glycine-extended precursor has been identified in secretory granules of rat anterior, intermediate, and neural pituitary and bovine intermediate pituitary. High …