COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART A, MOLECULAR & INTEGRATIVE PHYSIOLOGY
Abstract
The objective of the present study was to evaluate themodulation of acute stress response by dietary nucleotides(NT) in sole, Solea solea. A basal diet was supplemented with levels of 0 (normal diet), or 0.4 g NT/kg dry diet for 8 weeks. At the end of feeding trial, fish fed the normal and NT-supplemented diet were subjected to a standardized
protocol of disturbance and sampled over a 24 h recovery after the stressor exposure. Modulatory effects of
NT on acute stress response (cortisol and glucose), proopiomelanocortin (POMC) and cannabinoid receptor 1
splice variants (CB1A and CB1B) mRNA levels were studied. Both plasma cortisol and glucose levels of fish
fed NT-supplemented diet were significantly lower than fish fed the control diet at 1 and 4 h post-stress
time-points. There are no significant effects of dietary NT on POMC and HSP70 mRNA levels. In our study, both CB1A and CB1B trascript levels were induced in fish fed the normal diet at 1 and 4 h post-stress intervals. Collectively,
the results obtained suggest that dietary NT modulates the CB1-like receptor mRNA expressions leading to
attenuation in stressor-induced plasma cortisol level in sole.
