Expression of somatostatin receptor mRNAs is regulated in vivo by growth hormone, insulin, and insulin-like growth factor-I in rainbow trout (Oncorhynchus mykiss).
Somatostatins are a diverse family of peptide hormones that regulate various aspects of growth, development, and metabolism through interactions with numerous somatostatin receptor subtypes (SSTRs) on target tissues. In this study, we used rainbow trout to evaluate the effects of growth hormone (GH), insulin (INS), and insulin-like growth factor-I (IGF-I) on the expression of SSTR 1A, 1B and 2 mRNAs. GH regulated the expression of SSTRs in a subtype- and tissue-specific manner. GH reduced SSTR 1A, 1B, and 2 expression in optic tectum, reduced SSTR 1A and 1B expression in pancreas, reduced SSTR 1A expression in liver, and increased hepatic SSTR 1B expression. INS also regulated SSTR expression in a subtype- and tissue-specific manner. INS reduced SSTR 1B expression in optic tectum, increased SSTR 2 expression in pancreas, and increased SSTR 1B and 2 expression in liver. IGF-I generally decreased the expression of all SSTRs. These data indicate that GH, INS, and IGF-I modulate the expression of SSTRs and suggest that independent mechanisms may serve to regulate the various receptor subtypes.
Slagter
Barton J
BJ
Department of Biological Sciences and Regulatory Biosciences Center, North Dakota State University, Fargo, North Dakota 58105, United States.
Kittilson
Jeffrey
J
Sheridan
Mark A
MA
D000818:Animals; D001483:Base Sequence; D001786:Blood Glucose / Q000032:analysis; D017931:DNA Primers; D005260:Female; D013006:Growth Hormone / Q000502:physiology*; D007328:Insulin / Q000502:physiology*; D007334:Insulin-Like Growth Factor I / Q000502:physiology*; D008297:Male; D017686:Oncorhynchus mykiss; D012333:RNA, Messenger / Q000235:genetics*; D017481:Receptors, Somatostatin / Q000235:genetics*
D001786:Blood Glucose; D017931:DNA Primers; D007328:Insulin; D012333:RNA, Messenger; D017481:Receptors, Somatostatin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone