Immunocytochemical characterization of ACTH-like immunoreactivity in cerebral nerves and in endocrine cells of the pituitary and gastrointestinal tract by using region-specific antisera.

The development and use of region-specific antisera for characterizing pituitary and extrapituitary ACTH immunoreactivity are described. The pituitary corticotrophs and melanotrophs, as well as a system of cerebral nerves, contain antigenic determinants, indistinguishable from those of true, pituitary ACTH [1-39]. The distributional patterns of cerebral nerves, most probably containing ACTH [1-39], is of interest in view of documented behavioral effects of ACTH fragments, as well as the possible interaction between ACTH and certain opioid peptides. Studies on antropyloric gastrin cells, previously reported to contain immunoreactive ACTH-like material indicate that the main form of immunoreactive peptide stored in these cells contains only part of the ACTH [1-39] sequence. Its relation to fragments of the ACTH molecule, as well as to yet unknown (hormonal) peptides, is discussed.

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Characterization of antral gastrin cells with region-specific antisera.

Journal of Histochemistry & Cytochemistry ◽

10.1177/25.12.925341 ◽

1977 ◽

Vol 25 (12) ◽

pp. 1317-1321 ◽

Cited By ~ 61

Author(s):

L I Larsson ◽

J F Rehfeld

Keyword(s):

Cross Reactivity ◽

Terminal Region ◽

Gastrin Cells ◽

Related Peptide ◽

Specific Antisera

A number of gastrin antisera, which in radioimmunoassay systems showed no or negligible cross-reactivity towards the structurally and functionally related peptide cholecystokinin were found to react with both gastrin and cholecystokinin cells when used for immunocytochemistry. This discrepancy was shown to be due either to reactivity against a COOH-terminal region common to gastrin and cholecystokinin or to the occurrence of heterogenous antibody populations in the antisera. By differential absorptions the latter type of antisera could be rendered specific for gastrin. Antisera reactive against the NH2-terminal, middle or COOH-terminal regions of human heptadecapeptide gastrin were prepared and together with a specific cholecystokinin antiserum used for the characterization of antral gastrin cells of different species. The results indicate that only the COOH-terminal region of gastrin is conserved during evolution.

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Distribution of glucagon-like peptide I in canine and feline pancreas and gastrointestinal tract.

Journal of Histochemistry & Cytochemistry ◽

10.1177/34.9.3755450 ◽

1986 ◽

Vol 34 (9) ◽

pp. 1117-1121 ◽

Cited By ~ 23

Author(s):

C R Vaillant ◽

P K Lund

Keyword(s):

Gastrointestinal Tract ◽

Endocrine Cells ◽

Northern Blot Analysis ◽

Islet Cells ◽

Cleavage Product ◽

Antigenic Determinants ◽

Normal Pancreas ◽

Fetal Rat ◽

Islet Tissue ◽

Glucagon Like Peptide

Recently, a putative hormone, glucagon-like peptide I (GLP I), has been identified in the predicted sequences of the precursors to pancreatic glucagon in human, rat, hamster, and ox. The distribution of GLP I immunoreactivity in canine and feline pancreas and gastrointestinal tract was examined immunohistochemically and was compared with that of two other antigenic determinants of pancreatic pro-glucagon, i.e., glucagon and the NH2 terminus of glicentin. All three determinants occurred in the same population of islet cells in normal pancreas and in pancreas consisting predominantly of islet tissue from dogs with canine pancreatic acinar atrophy. Northern blot analysis of mRNA from the latter tissue, using a rat pre-pro-glucagon complementary DNA probe, revealed a single mRNA species similar in size to the pre-pro-glucagon mRNA detected in fetal rat pancreas. The three antigenic determinants of pancreatic pro-glucagon were co-localized also in intestinal L-cells and in canine gastric A-cells. Canine and feline pancreatic pro-glucagons therefore resemble those identified in other mammals and may also occur in gastrointestinal endocrine cells. Although there is evidence that the GLP I sequence is not liberated from pancreatic pro-glucagon, our results raise the possibility that this putative hormone may be a cleavage product of pro-glucagon in the gastrointestinal tract.

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Common Antigenic Sites in Human, Bovine and Porcine Fibrinogens

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650157 ◽

1981 ◽

Vol 45 (02) ◽

pp. 169-172 ◽

Cited By ~ 2

Author(s):

Czeslaw S Cierniewski

Keyword(s):

Antigenic Determinants ◽

Antigenic Sites ◽

Specific Antisera ◽

Antigenic Homology ◽

Polypeptide Chains ◽

Fibrinogen Molecule

SummarySpecific antisera to the Aα, Bβ and γ chains of porcine fibrinogen were used to characterize an antigenic homology of human, bovine, and porcine fibrinogens. Antigenic determinants shared by these fibrinogens were mostly formed by the Aα chain. However, in the case of bovine and porcine fibrinogens they were also found in the Bβ and γ polypeptide chains. The results reported here show that the Aα chain determinants exposed on the intact fibrinogen molecule are conserved to a considerably larger extent than those of the Bβ and γ chains.

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