Glucagon and insulin secretion during acid-base alterations
Previously, we reported that change from the normal pH of 7.4 surrounding the islet cells to 7.8 results in a decreased B-cell response to 16.6 mM glucose, 10 mM arginine or 400 µg/ml tolbutamide. In the present report we studied the effect of modifications in the extracellular pH on glucose- and ar...
| Autores principales: | , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
1983
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| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/139101 |
| Aporte de: |
| id |
I19-R120-10915-139101 |
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| record_format |
dspace |
| institution |
Universidad Nacional de La Plata |
| institution_str |
I-19 |
| repository_str |
R-120 |
| collection |
SEDICI (UNLP) |
| language |
Inglés |
| topic |
Medicina extracellular pH extracellular alkalosis rat pancreas glucagon secretion insulin secretion |
| spellingShingle |
Medicina extracellular pH extracellular alkalosis rat pancreas glucagon secretion insulin secretion Rebolledo, Oscar Remigio Gagliardino, Juan José Glucagon and insulin secretion during acid-base alterations |
| topic_facet |
Medicina extracellular pH extracellular alkalosis rat pancreas glucagon secretion insulin secretion |
| description |
Previously, we reported that change from the normal pH of 7.4 surrounding the islet cells to 7.8 results in a decreased B-cell response to 16.6 mM glucose, 10 mM arginine or 400 µg/ml tolbutamide. In the present report we studied the effect of modifications in the extracellular pH on glucose- and arginine-induced glucagon and insulin secretion by the perfused rat pancreas. It was found that at pH 7.8, arginine-induced glucagon secretion was significantly greater than at pH 7.4. On the other hand, the switch from pH 7.4 to 7.8 in a pancreas already stimulated by either low glucose or arginine, produced fast and transient glucagon release. Sequential extracellular pH changes from 7.4 to 7.8 and back to 7.4 in the presence of 8.3 mM glucose and a 5 mM arginine stimulus demonstrated that A- and B-cells rapidly modify their secretion in response to extracellular alkalosis in opposite directions. While glucagon output was enhanced (mean secretory rates at pH 7.4, 0.692 ± 0.042 ng/min and 0.948 ± 0.57 at pH 7.8), insulin secretion was clearly reduced (72.6 ± 6.2 ng/min and 35.7 ± 2.8 ng/min at pH 7.4 and 7.8, respectively). The above observations, together with our previously reported data, indicate that extracellular pH plays an important role in the regulation of glucagon and insulin release. Particularly, extracellular alkalosis enhances A-cell response to 2.3 mM glucose and 5 mM arginine while partially inhibiting B-cell secretion in the perfused rat pancreas. |
| format |
Articulo Articulo |
| author |
Rebolledo, Oscar Remigio Gagliardino, Juan José |
| author_facet |
Rebolledo, Oscar Remigio Gagliardino, Juan José |
| author_sort |
Rebolledo, Oscar Remigio |
| title |
Glucagon and insulin secretion during acid-base alterations |
| title_short |
Glucagon and insulin secretion during acid-base alterations |
| title_full |
Glucagon and insulin secretion during acid-base alterations |
| title_fullStr |
Glucagon and insulin secretion during acid-base alterations |
| title_full_unstemmed |
Glucagon and insulin secretion during acid-base alterations |
| title_sort |
glucagon and insulin secretion during acid-base alterations |
| publishDate |
1983 |
| url |
http://sedici.unlp.edu.ar/handle/10915/139101 |
| work_keys_str_mv |
AT rebolledooscarremigio glucagonandinsulinsecretionduringacidbasealterations AT gagliardinojuanjose glucagonandinsulinsecretionduringacidbasealterations |
| bdutipo_str |
Repositorios |
| _version_ |
1764820457041690628 |