TY - JOUR
T1 - The effects of starvation and temperature acclimation on pentose phosphate pathway dehydrogenases in brook trout liver
AU - Yamauchi, Toshio
AU - Stegeman, John J.
AU - Goldberg, Erwin
N1 - Funding Information:
1 This research was supported in part by National Science Foundation Grant GB - 7271 and by U. S. Public Health Service Predoctoral Fellowships 4 F01 GM 43657-03 (T.Y.) and 4 FOl GM 41704-03 (J.S.). Z Send reprint requests to Toshio Yamauchi. Present address: Department of Biology, The University of Texas System C!ancer Center, M. D. Anderson Hospital and Tumor Institute at Houston, 6723 Bertner Avenue, Houston, Texas 77025. *Present address: Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543. ’ Abbreviations: Glucose-6-phosphate dehydrogenase, GGPD; 6-phosphogluconate dehydrogenase, 6-PGD; pentose phosphate pathway, PPP: hexose-6-phosphate dehydrogenase, HGPD.
Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1975/3
Y1 - 1975/3
N2 - Temperature and starvation were found to be factors which affected the PPP dehydrogenase activities in brook trout liver. Fish acclimated at 5 °C possessed greater levels of G6PD, H6PD, and 6PGD activity than those fish maintained at 10 or 15 °C. This phenomenon was probably associated with increased lipogenesis during cold acclimation. During starvation hepatic G6PD and 6PGD activities decreased, whereas H6PD activity increased slightly. Upon refeeding, the G6PD level gradually increased, but the "overshoot" in enzyme activity reported in mammalian studies was not observed. When both cold acclimation and starvation were studied simultaneously, regulation by temperature was initially the dominant control factor. After 6 wk at 5 °C, there was no difference in specific activities between starved and fed fish. However, fish maintained at 5 °C for longer than 2 mo did show the normal response to starvation and refeeding. Therefore, regulation of the PPP by temperature appears to be a transitory phenomenon and may be associated with temporary metabolic reorganization in the fish.
AB - Temperature and starvation were found to be factors which affected the PPP dehydrogenase activities in brook trout liver. Fish acclimated at 5 °C possessed greater levels of G6PD, H6PD, and 6PGD activity than those fish maintained at 10 or 15 °C. This phenomenon was probably associated with increased lipogenesis during cold acclimation. During starvation hepatic G6PD and 6PGD activities decreased, whereas H6PD activity increased slightly. Upon refeeding, the G6PD level gradually increased, but the "overshoot" in enzyme activity reported in mammalian studies was not observed. When both cold acclimation and starvation were studied simultaneously, regulation by temperature was initially the dominant control factor. After 6 wk at 5 °C, there was no difference in specific activities between starved and fed fish. However, fish maintained at 5 °C for longer than 2 mo did show the normal response to starvation and refeeding. Therefore, regulation of the PPP by temperature appears to be a transitory phenomenon and may be associated with temporary metabolic reorganization in the fish.
UR - http://www.scopus.com/inward/record.url?scp=0016637865&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0016637865&partnerID=8YFLogxK
U2 - 10.1016/0003-9861(75)90436-1
DO - 10.1016/0003-9861(75)90436-1
M3 - Article
C2 - 1130788
AN - SCOPUS:0016637865
SN - 0003-9861
VL - 167
SP - 13
EP - 20
JO - Archives of biochemistry and biophysics
JF - Archives of biochemistry and biophysics
IS - 1
ER -