| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Submitted on April 8, 2003
Accepted on May 23, 2003
1 Department of Biological Sciences, Faculty of Science, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9. Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2R7. Salk Institute, La Jolla, California, USA, 92037
* To whom correspondence should be addressed. E-mail: john.chang{at}ualberta.ca.
Using Southern blot analysis of RT-PCR products, mRNA for three different somatostatin (SS) precursors (PSS-I, -II, and -III), which encode for SS14, goldfish brain (gb)SS28, and [Pro (2)]SS14, respectively, were detected in goldfish hypothalamus. PSS-I and -II mRNA, but not PSS-III mRNA, were also detected in cultured pituitary cells. We subsequently examined the effects of the mature peptides, SS14, gbSS28, and [Pro2]SS14, on somatotrope signaling and growth hormone (GH) secretion. gbSS28 was more potent than either SS14 or [Pro2]SS14 in reducing basal GH release, but was the least effective in reducing basal cellular cAMP. The ability of SS14, [Pro2]SS14 and gbSS28 to attenuate GH responses to gonadotropin-releasing hormone were comparable. However, gbSS28 was less effective than SS14 and [Pro2]SS14 in diminishing dopamine- and pituitary adenylate cyclase-activating polypeptide-stimulated GH release, as well as GH release resulting from the activation of their underlying signaling cascades. In contrast, the actions of a different 28 amino acid SS, mammalian SS28, were more similar to those of SS14 and [Pro2]SS14. We conclude that, in goldfish, SS's differentially couple to the intracellular cascades regulating GH secretion from pituitary somatotropes. This raises the possibility that such differences may allow for the selective regulation of various aspects of somatotrope function by different SS peptides.
This article has been cited by other articles:
 |
|
 |
|
  C. Hernandez, E. Carrasco, R. Casamitjana, R. Deulofeu, J. Garcia-Arumi, and R. Simo Somatostatin Molecular Variants in the Vitreous Fluid: A comparative study between diabetic patients with proliferative diabetic retinopathy and nondiabetic control subjects Diabetes Care, August 1, 2005; 28(8): 1941 - 1947. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. F. Canosa, S. Unniappan, and R. E. Peter Periprandial changes in growth hormone release in goldfish: role of somatostatin, ghrelin, and gastrin-releasing peptide Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2005; 289(1): R125 - R133. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Unniappan and R. E. Peter In vitro and in vivo effects of ghrelin on luteinizing hormone and growth hormone release in goldfish Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2004; 286(6): R1093 - R1101. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |
