Brain monoamine changes modulate the corticotropin-releasing hormone receptor 1-mediated behavioural response to acute thermal stress in zebrafish larvae.

While central monoamines play a role in regulating stress-related locomotory activity, the modulation of monoamines by the corticosteroid stress axis in shaping acute behavioural responses are unclear. We investigated whether the corticotropin-releasing hormone receptor 1 (Crhr1) modulation of stress-related behavioral response involves monoamine regulation by subjecting Crhr1 knockout (crhr1) zebrafish (Danio rerio) to an acute thermal stressor (TS: +5 °C above ambient for 60 min). The TS-induced cortisol response and hyper locomotory activity in the WT larvae was abolished in fish lacking Crhr1.