Hypothalamus-pituitary-interrenal

CBG corticosteroid binding globulin HPI hypothalamus—pituitary—interrenal... 

In bony fishes, corticosteroids are secreted from the interrenal tissues (analogous to the adrenal cortex) located in the head kidney region121 182. Cortisol is the major steroid released from these cells in response to neuroendocrine stimulation emanating from the hypothalamus and the pituitary (see Chapter 12). The release of cortisol in response to stress has been characterized in several species and also in response to different stressors and this topic has been extensively reviewed1011 70 182. Cortisol... 

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