Which cells react negatively to stress?

Answer 1

The part of the human brain which controls the body's response to stress is the limbic system in the central nervous system and the sympathetic nervous system of the peripheral nervous system. The sympathetic nervous system has a hand in most biological responses related to stress, such as pupil dilation and secretion of adrenaline from the adrenal glands. The nervous system originates primarily from the spinal cord, but it has no specific nervous center. The limbic system regulates chemicals related to the activation of the sympathetic nervous system. The amygdala is often referred to the emotional center of the brain, producing responses such as rage or fear which prepare the body for a response to stimulus. The orbitofrontal complex is related to decision and action, and the hypothalamus controls arousal. All of these are related to stress response.

During this response, several things may occur. Pupils dilate, digestion ceases, and the bladder may relax. The circulatory system will up-regulate, increasing breathing rates, heart rate, blood flow, and blood pressure. Muscle blood vessels will dilate, preparing the body for quick reaction. Extended periods of arousal at high or low levels ultimately lead to exhaustion.