Stress response in silver catfish (Rhamdia quelen) exposed to the essential oil of Hesperozygis ringens.
This study investigated the effects of prolonged exposure of silver catfish (Rhamdia quelen) to the essential oil (EO) of Hesperozygis ringens. Ventilatory rate (VR), stress and metabolic indicators, energy enzyme activities, and mRNA expression of adenohypophyseal hormones were examined in specimens that were exposed for 6 h to 0 (control), 30 or 50 µL L(-1) EO of H. ringens in water. Reduction in VR was observed in response to each treatment, but no differences were found between treatments. Plasma glucose, protein, and osmolality increased in fish exposed to 50 µL L(-1). Moreover, lactate levels increased after exposure to both EO concentrations. Plasma cortisol levels were not changed by EO exposure. Fish exposed to 30 µL L(-1) EO exhibited higher glycerol-3-phosphate dehydrogenase (G3PDH) activity, while exposure to 50 µL L(-1) EO elicited an increase in glucose-6-phosphate dehydrogenase (G6PDH), fructose-biphosphatase (FBP), and 3-hydroxyacyl-CoA-dehydrogenase (HOAD) activities compared with the control group. Expression of growth hormone (GH) only decreased in fish exposed to 50 µL L(-1) EO, while somatolactin (SL) expression decreased in fish exposed to both concentrations of EO. Exposure to EO did not change prolactin expression. The results indicate that GH and SL are associated with energy reorganization in silver catfish. Fish were only slightly affected by 30 µL L(-1) EO of H. ringens, suggesting that it could be used in practices where a reduction in the movement of fish for prolonged periods is beneficial, i.e., such as during fish transportation.
Post-Graduate Program in Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Cândida
C
Toni
Juan Antonio
JA
Martos-Sitcha
Ignacio
I
Ruiz-Jarabo
Juan Miguel
JM
Mancera
Gonzalo
G
Martínez-Rodríguez
Carlos Garrido
CG
Pinheiro
Berta Maria
BM
Heinzmann
Bernardo
B
Baldisserotto
D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D017756:Aquaculture / Q000379:methods*; D001786:Blood Glucose / Q000187:drug effects; D001798:Blood Proteins / Q000187:drug effects; D002397:Catfishes / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D029941:Fish Proteins / Q000378:metabolism; D006597:Fructose-Bisphosphatase / Q000378:metabolism; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D005993:Glycerolphosphate Dehydrogenase / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism; D013006:Growth Hormone / Q000378:metabolism; D006854:Hydrocortisone / Q000378:metabolism; D019686:Lamiaceae / Q000737:chemistry*; D009822:Oils, Volatile / Q000009:adverse effects*; D009994:Osmolar Concentration; D010101:Oxygen Consumption / Q000187:drug effects; D010907:Pituitary Hormones / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D013053:Spectrophotometry / Q000662:veterinary; D013312:Stress, Physiological / Q000187:drug effects* / Q000502:physiology
D001786:Blood Glucose; D001798:Blood Proteins; D017931:DNA Primers; D029941:Fish Proteins; D006023:Glycoproteins; D009822:Oils, Volatile; D010907:Pituitary Hormones; C064448:somatolactin protein, fish; D013006:Growth Hormone; D005993:Glycerolphosphate Dehydrogenase; D015094:3-Hydroxyacyl CoA Dehydrogenases; D005954:Glucosephosphate Dehydrogenase; D006597:Fructose-Bisphosphatase; D006854:Hydrocortisone