Growth hormone and insulin-like growth factor-1 differentially stimulate the expression of preprosomatostatin mRNAs in the Brockmann bodies of rainbow trout, Oncorhynchus mykiss

Gregory T. Melroe, Melissa M. Ehrman, Jeffrey D. Kittilson, Mark A. Sheridan

Research output: Contribution to journalArticle

9 Scopus citations

Abstract

We previously characterized three cDNAs obtained from the endocrine pancreas (Brockmann body) of rainbow trout that encode for distinct preprosomatostatin (PPSS) molecules: PPSS I containing somatostain-14 (SS-14) at its C-terminus and two separate PPSS IIs, PPSS II and PPSS II″, containing [Tyr7,Gly10]-SS-14 at their C-termini. In this study, we examined the control of PPSS I, PPSS II , and PPSS II″ mRNA expression by growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Rainbow trout implanted with GH for 21 days displayed elevated pancreatic expression of all PPSS mRNAs compared to control animals. Growth hormone directly stimulated the expression of all pancreatic PPSS mRNAs in vitro in a dose-dependent manner; however, GH was a more potent stimulator of PPSS II expression than of PPSS I or PPSS II″ expression. Insulin-like growth factor-1 also directly stimulated the expression of PPSS mRNAs in a dose-dependent manner in Brockmann bodies incubated in vitro; IGF-1 was a more potent stimulator of PPSS I and PPSS II expression than of PPSS II″ expression. These results indicate that the expression of PPSS mRNAs in the Brockmann body of trout is differentially regulated by GH and IGF-1 and suggest that SS mediate the feedback regulation of GH and IGF-1.

Original languageEnglish
Pages (from-to)353-359
Number of pages7
JournalGeneral and Comparative Endocrinology
Volume136
Issue number3
DOIs
StatePublished - May 1 2004

Keywords

  • Growth hormone
  • Insulin-like growth factor 1
  • Preprosomatostatin expression
  • Rainbow trout

Fingerprint Dive into the research topics of 'Growth hormone and insulin-like growth factor-1 differentially stimulate the expression of preprosomatostatin mRNAs in the Brockmann bodies of rainbow trout, Oncorhynchus mykiss'. Together they form a unique fingerprint.

Cite this