Stress response

Stress response

When the sympathetic nervous system is activated, the brain stimulates the adrenal medulla. The cells in the medulla immediately secrete adrenaline (80%) and noradrenaline (20%).

 

These hormones stimulate adrenergic receptors throughout the whole body. Adrenaline mobilises glucose, fatty acids and energy, and increases heart rate and force of muscle contraction.

1

I. Acute stress results in higher blood pressure within seconds.

II. Chronic stress is mediated by noradrenaline.