QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online August 8, 2003

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Milligan, C. L. Search for Related Content PubMed PubMed Citation Articles by Milligan, C. L.

A regulatory role for cortisol in muscle glycogen metabolism in rainbow trout Oncorhynchus mykiss Walbaum

C. Louise Milligan

Department of Biology, The University of Western Ontario, London, ON N6A 5B7 Canada

View larger version (14K): [in a new window]   Fig. 1. Plasma cortisol levels in fish injected with either saline (control, N=8; filled squares), metyrapone (N=8; open circles) prior to exercise or cortisol (N=8; filled triangles) after a 5 min period of exercise (indicated by rectangular bar). R, the pre-exercise, post-injection value. Values are means ± 1 S.E.M.. *Significant difference (P<0.05) from the pre-exercise value; significant difference (P<0.05) from the corresponding control value.

View larger version (18K): [in a new window]   Fig. 2. Plasma adrenaline (A) and noradrenaline (B) levels prior to and following 5 min of exercise in fish treated with metyrapone or saline prior to exercise, or cortisol after exercise. R, pre-exercise, post-injection value. Values are means ± 1 S.E.M.. (N=8 for each group). *Significant difference (P<0.05) from pre-exercise value.

View larger version (20K): [in a new window]   Fig. 3. Muscle glycogen (A) and lactate (B) concentrations in fish treated with metyrapone or saline prior to exercise or cortisol after 5 min of exercise. Muscle glycogen concentration is expressed as glycosyl units. R indicates pre-exercise, post-injection value. Values are means ± 1 S.E.M.. (N=8 for each group). *Significant difference (P<0.05) from pre-exercise value; significant difference (P<0.05) from corresponding control value.

View larger version (21K): [in a new window]   Fig. 4. Muscle glycogen phosphorylase a (A) and glycogen synthase I (B) activities prior to and following 5 min of exercise. Glycogen phosphorylase activity is expressed as the percentage of the total activity (measured in the presence of 5'AMP) in the active form (measured in the absence of 5'AMP). Glycogen synthase activity is expressed as the percentage of the total activity (measured in the presence of glucose-6-phosphate) in the active form (measured in the absence of glucose-6-phosphate). R, pre-exercise, post-injection value. Values are means ± 1 S.E.M.. (N=8 for each group). *Significant difference (P<0.05) from the pre-exercise value; significant difference (P<0.05) from the corresponding control value.

View larger version (19K): [in a new window]   Fig. 5. Muscle glucose (A) and glucose-6-phosphate (B) concentrations in fish treated with metyrapone or saline prior to exercise or cortisol after 5 min of exercise. R, pre-exercise, post-injection value. Values are means ± 1 S.E.M.. (N=8 for each group). *Significant difference (P<0.05) from the pre-exercise value; significant difference (P<0.05) from the corresponding control value.