Effects of preproglucagon-derived peptides and exendins on steroid-hormone secretion from dispersed adrenocortical cells of normal and streptozotocin-induced diabetic rats

  • Authors:
    • Ludwik K. Malendowicz
    • Raffaella Spinazzi
    • Gastone G. Nussdorfer
    • Marcin Trejter
  • View Affiliations

  • Published online on: July 1, 2003     https://doi.org/10.3892/ijmm.12.1.115
  • Pages: 115-119
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Abstract

Many lines of evidence have shown that preproglucagon-derived peptides affect steroid secretion from dispersed adrenocortical cells, and that streptozotocin (STZ)-induced experimental diabetes alters adrenocortical-cell function. Hence, we compared the effects of glucagon, glucagon-like peptide (GLP)-1 and GLP-2 on basal and ACTH-stimulated secretion of dispersed adrenocortical cells from normal and STZ-induced diabetic rats. We also examined the effects of exendins (EX) 3 and 4, because EX4 is known to be a potent and long-lasting agonist of GLP-1 receptors. STZ-induced diabetes moderately enhances basal and ACTH-stimulated secretion from dispersed zona glomerulosa (ZG) cells, without significantly affecting corticosterone production from dispersed zona fasciculata-reticularis (ZF/R) cells. In normoglycemic rats, glucagon increased basal aldosterone and corticosterone secretion from ZG and ZF/R cells, GLP-2 raised both basal and ACTH-stimulated aldosterone secretion and ACTH-stimulated corticosterone output, and EX4 increased basal corticosterone secretion. In contrast, glucagon, GLP-2 and EX4 did not elicit secretory responses from adrenocortical cells of diabetic rats. GLP-1 and EX3 did not alter secretion of dispersed adrenocortical cells of either normal or STZ-treated rats. Taken together, our findings indicate that preproglucagon-derived peptides enhance steroid secretion from adrenocortical cells of normal, but not STZ-induced diabetic rats. It is suggested that the prolonged exposure to low concentrations of insulin causes unresponsiveness of adrenocortical cells to glucagon, GLP-2 and EX4, which may contribute to the hyporeninemic hypoaldosteronism and alterations in glucocorticoid metabolism occurring in experimental diabetes.

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July 2003
Volume 12 Issue 1

Print ISSN: 1107-3756
Online ISSN:1791-244X

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Spandidos Publications style
Malendowicz LK, Spinazzi R, Nussdorfer GG and Trejter M: Effects of preproglucagon-derived peptides and exendins on steroid-hormone secretion from dispersed adrenocortical cells of normal and streptozotocin-induced diabetic rats. Int J Mol Med 12: 115-119, 2003.
APA
Malendowicz, L.K., Spinazzi, R., Nussdorfer, G.G., & Trejter, M. (2003). Effects of preproglucagon-derived peptides and exendins on steroid-hormone secretion from dispersed adrenocortical cells of normal and streptozotocin-induced diabetic rats. International Journal of Molecular Medicine, 12, 115-119. https://doi.org/10.3892/ijmm.12.1.115
MLA
Malendowicz, L. K., Spinazzi, R., Nussdorfer, G. G., Trejter, M."Effects of preproglucagon-derived peptides and exendins on steroid-hormone secretion from dispersed adrenocortical cells of normal and streptozotocin-induced diabetic rats". International Journal of Molecular Medicine 12.1 (2003): 115-119.
Chicago
Malendowicz, L. K., Spinazzi, R., Nussdorfer, G. G., Trejter, M."Effects of preproglucagon-derived peptides and exendins on steroid-hormone secretion from dispersed adrenocortical cells of normal and streptozotocin-induced diabetic rats". International Journal of Molecular Medicine 12, no. 1 (2003): 115-119. https://doi.org/10.3892/ijmm.12.1.115