Cortisol response of green sturgeon to acid-infusion stress.
Cortisol and lactate are classic indicators of stress in fishes and their interactive effects on metabolism during recovery from stress have recently become a subject of more intense study. We examined how stressing green sturgeon through acid infusion affected the cortisol response and lactate metabolism in green sturgeon (Acipenser medirostris). Both lactic acid (0.3 M) and HCl (0.3 N) infusion (infusion volumes 1.5 ml kg(-1)) elicited an immediate cortisol response (21.61+/-4.61 ng ml(-1) and 17.50+/-3.00 ng ml(-1), respectively). Lactic acid prolonged the cortisol response compared to HCl (90 min vs. 25 min). Neutralized lactate (0.23 M; with 1 N NaOH; final pH 7.8) and NaCl (0.9%) infusion (infusion volumes 1.5 ml kg(-1)) did not affect plasma cortisol. Sturgeon infused with lactic acid showed a faster rate of lactate disappearance from plasma than those with neutralized lactic acid. We relate these findings to lactate metabolism following exercise, acid-infusion and air immersion stress in fishes.
Warren
Daniel E
DE
Department of Wildlife, Fish, and Conservation Biology, Davis, CA 95616, USA. Daniel_E_Warren@brown.edu
Matsumoto
Shinsyu
S
Roessig
Julie M
JM
Cech
Joseph J
JJ
D000136:Acid-Base Equilibrium; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D005399:Fishes / Q000502:physiology*; D006851:Hydrochloric Acid / Q000009:adverse effects*; D006854:Hydrocortisone / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007263:Infusions, Parenteral; D019344:Lactic Acid / Q000008:administration & dosage / Q000009:adverse effects*; D010100:Oxygen / Q000097:blood; D010805:Physical Conditioning, Animal; D013312:Stress, Physiological; D013997:Time Factors
D001786:Blood Glucose; D019344:Lactic Acid; D006851:Hydrochloric Acid; D010100:Oxygen; D006854:Hydrocortisone