Size heterogeneity of beta-MSH in ectopic ACTH-producing tumors: presence of beta-LPH-like peptide.
J Clin Endocrinol Metab
; 42(1): 33-40, 1976 Jan.
Article
em En
| MEDLINE
| ID: mdl-175084
ABSTRACT
Gel chromatographic, immunologic and biologic properties of beta-melanocyte-stimulating hormone (beta-MSH) in tumor tissues obtained from eight patients with the ectopic ACTH syndrome were studied and compared to those of pituitary beta-MSH. Size heterogeneity of immunoreactive beta-MSH was found in all the tumors studied as well as in normal human pituitaries. Both the tumors and pituitaries contained immunoreactive beta-MSH of a larger molecular size than the well-characterized beta-MSH of small molecular size. The large molecular weight beta-MSH also predominated in the plasma. It was found to be bioactive by an in vitro MSH assay, immunologically indistinguishable from human beta-MSH, and chromatographically very similar to beta-lipotropic hormone (beta-LPH). Tryptic digestion of the large molecular weight beta-MSH under controlled conditions promptly produced bioactive beta-MSH of small molecular size, followed by the appearance of immunologically active but biologically inert fragments. These results suggest that the ectopic ACTH-producing tumor as well as the pituitary elaborate beta-LPH-like peptide which might be the predominant component of immunoreactive beta-MSH in man.
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Base de dados:
MEDLINE
Assunto principal:
Hormônios Estimuladores de Melanócitos
/
Hormônio Adrenocorticotrópico
/
Síndromes Endócrinas Paraneoplásicas
Limite:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
J Clin Endocrinol Metab
Ano de publicação:
1976
Tipo de documento:
Article