TY - JOUR
T1 - Somatostatin-14 and somatostatin-25 stimulate glycogenolysis in rainbow trout, oncorhynchus mykiss, liver incubated in vitro
T2 - A systemic role for somatostatins
AU - Eilertson, Carmen D.
AU - O'connor, Pamela K.
AU - Sheridan, Mark A.
N1 - Funding Information:
We are grateful to Kim Michelsen for her technical assistance and to the North Dakota State Department of Game and Fish and the U.S. Fish and Wildlife Service (Garrison National Hatchery) for providing experimental animals. We also thank Dr. Erika Pli-setskaya, University of Washington, for the generous gift of salmon somatostatin-25. This work was supported by grants from the NIH (RR 07206-06) and the NSF (BBS 8704115, DCB 8901380) to M.A.S.
PY - 1991/5
Y1 - 1991/5
N2 - The effects of somatostatin-14 (SS-14) and salmon somatostatin-25 (sSS-25) on hepatic glycogenolysis were studied by incubating rainbow trout liver pieces in vitro. Glycogen content in untreated liver pieces cultured for 3 and 5 hr was 28.6 ± 7.6 mg/g fresh wt. and 21.5 ± 6.6 U, respectively. Treatment of liver pieces with either SS-14 or sSS-25 resulted in significant glycogen depletion; sSS-25 appeared more potent in this regard. Equimolar concentrations (10-8 M) of SS-14 or sSS-25 reduced glycogen content to 10.6 ± 1.6 and 2.6 ± 2.2 U, respectively, in liver pieces incubated for 3 hr. Alterations in liver glycogen content were reflected in glucose release into medium. Basal release of glucose into culture medium over the course of a 3-hr incubation was 20 ± 5.6 μmol/g dry wt. Both SS-14 and sSS-25 stimulated a rapid increase (500 and 600%, respectively) in glucose release during the first 0.5 hr of incubation. After 3 hr, SS-14 and sSS-25 stimulated glucose release over basal levels to 116 ± 9.3 and 153 ± 16 U, respectively. Both SS-14 and sSS-25 stimulated glucose release in a dose-dependent manner; ED50 for both peptides was ca. 5 × 10t-8 M. These results indicate that both SS-14 and sSS-25 directly mediate hepatic glycogenolysis in rainbow trout.
AB - The effects of somatostatin-14 (SS-14) and salmon somatostatin-25 (sSS-25) on hepatic glycogenolysis were studied by incubating rainbow trout liver pieces in vitro. Glycogen content in untreated liver pieces cultured for 3 and 5 hr was 28.6 ± 7.6 mg/g fresh wt. and 21.5 ± 6.6 U, respectively. Treatment of liver pieces with either SS-14 or sSS-25 resulted in significant glycogen depletion; sSS-25 appeared more potent in this regard. Equimolar concentrations (10-8 M) of SS-14 or sSS-25 reduced glycogen content to 10.6 ± 1.6 and 2.6 ± 2.2 U, respectively, in liver pieces incubated for 3 hr. Alterations in liver glycogen content were reflected in glucose release into medium. Basal release of glucose into culture medium over the course of a 3-hr incubation was 20 ± 5.6 μmol/g dry wt. Both SS-14 and sSS-25 stimulated a rapid increase (500 and 600%, respectively) in glucose release during the first 0.5 hr of incubation. After 3 hr, SS-14 and sSS-25 stimulated glucose release over basal levels to 116 ± 9.3 and 153 ± 16 U, respectively. Both SS-14 and sSS-25 stimulated glucose release in a dose-dependent manner; ED50 for both peptides was ca. 5 × 10t-8 M. These results indicate that both SS-14 and sSS-25 directly mediate hepatic glycogenolysis in rainbow trout.
UR - http://www.scopus.com/inward/record.url?scp=0025782968&partnerID=8YFLogxK
U2 - 10.1016/0016-6480(91)90183-7
DO - 10.1016/0016-6480(91)90183-7
M3 - Article
C2 - 1677340
AN - SCOPUS:0025782968
VL - 82
SP - 192
EP - 196
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
SN - 0016-6480
IS - 2
ER -