Browsing by Author "Herrera, M."
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- Comparative gene expression and histological analysis of skin response to injury in two congeneric flatfish with striking skin morphological differences, the brill (Scophthalmus rhombus) and the turbot (Scophthalmus maximus)Publication . Estêvão, J.; Millan, A.; Pardo, B. G.; Fernandez, C.; Rubiolo, J.; Herrera, M.; Gomez-Tato, A.; Ronza, P.; Cabaleiro, S.; Quiroga, M., I.; Power, Deborah; Martinez, P.Analysis of the morphological and genetic differences in the skin response to injury between Turbot and Brill.
- Effect of amino acid supplementation and stress on expression of molecular markers in meagre (Argyrosomus regius)Publication . Herrera, M.; Matias, A. C.; Soares, F.; Ribeiro, L.; Moreira, Márcio; Salamanca, N.; Jerez-Cepa, I.; Mancera, J. M.; Astola, A.The objectives of this work were: 1) develop of molecular stress biomarkers obtaining sequence data of different transcripts, 2) study the molecular stress response through the expression quantification of key gene involved in it, and 3) assess the effects of dietary amino acid additives on stress response in meagre meagres (Argyrososmus regius). Fish batches were fed two experimental diets with tryptophan (Trp) or aspartate (Asp) added for seven days. Before sampling fish were submitted to confinement/netting stress during 1 h, except control fish. Therefore fish were sampled before and after stress (1 h and 6 h post-stress). The sampling consisted of blood and tissues (brain, hypophysis and liver). Several gene expressions related to the stress response were measured in those tissues, and the cloning of corticotropin-releasing hormone (crh), corticotropin-releasing hormone binding protein (crh-bp), and thyrotropin-releasing hormone (trh) has been reported in meagre for the first time. In fact, fish fed an additional Asp diet did not present any sl, prl and gh expression changes, as for the control group. Contrarily, the Trp diet altered the prl and gh expressions after stress. For crh and crh-bp expressions, no significant differences were detected within the Asp diet hence that amino acid improved the stress response. However, Asp feeding, but not Trp, enhanced pomc-a expression after stress. Hsp70 expression varied for every treatment, including the control feeding, indicating a late response at 6 h post-stress sampling, where both Asp and Trp treatments increased these expressions significantly. Concluding, the response of molecular stress markers to amino acid enriched diets was diverse. The stressor did not change significantly the relative expression of most analyzed genes for control feeding groups, though the Asp supplemented diet was more effective for attenuating molecular markers than the Trp one.
- Physiological short-term response to sudden salinity change in the Senegalese sole (Solea senegalensis)Publication . Herrera, M.; Aragão, C.; Hachero-Cruzado, Ismael; Ruiz-Jarabo, I.; Vargas-Chacoff, L.; Mancera, J. M.; Conceição, L. E. C.The physiological responses of Senegalese sole to a sudden salinity change were investigated. The fish were first acclimated to an initial salinity of 37.5 ppt for 4 h. Then, one group was subjected to increased salinity (55 ppt) while another group was subjected to decreased salinity (5 ppt). The third group (control group) remained at 37.5 ppt. We measured the oxygen consumption rate, osmoregulatory (plasma osmolality, gill and kidney Na+,K+-ATPase activities) and stress (plasma cortisol and metabolites) parameters 0.5 and 3 h after transfer. Oxygen consumption at both salinities was higher than for the control at both sampling times. Gill Na+,K+-ATPase activity was significantly higher for the 55 ppt salinity at 0.5 h. Plasma osmolality decreased in the fish exposed to 5 ppt at the two sampling times but no changes were detected for high salinities. Plasma cortisol levels significantly increased at both salinities, although these values declined in the low-salinity group 3 h after transfer. Plasma glucose at 5 ppt salinity did not vary significantly at 0.5 h but decreased at 3 h, while lactate increased for both treatments at the first sampling time and returned to the control levels at 3 h. Overall, the physiological response of S. senegalensis was immediate and involved a rise in oxygen consumption and plasma cortisol values as well as greater metabolite mobilization at both salinities.