Fight-or-flight reaction

Activity often involves mass discharge of entire system Predominates during emergency "fight-or-flight" reactions and exercise... 

Under certain circumstances, anxiety is an appropriate emotional response. We expect a person to feel sad after a signihcant loss such as the death of a loved one, and it is eqnally reasonable for a person to feel fearful and anxious when faced with a frightening situation such as a painful or risky medical procedure. Indeed, in the context of the fight or flight reaction readily witnessed in nature when a predator is lurking near its intended prey, the physical and mental symptoms of anxiety can indeed be adaptive. This anxiety clearly serves as an appropriate alarm that potential danger is nearby and readies the individnal for a self-protective response. 

The autonomic nervous system is divided into the sympathetic and parasympathetic components, which typically exert opposing effects. The sympathetic system is involved in the fight or flight reaction (increased blood pressure and heart rate, and accommodation for increased vision, for example) that prepares the organism for stressful situations. The parasympathetic system conversely establishes a more relaxed situation, for instance, the rest period after a meal. The autonomic nervous system that is responsible for the independent control of the mechanical and secretory functions of the gastrointestinal tract is sometimes called the enteric system. 

Inhalants make the heart extra sensitive to adrenaline, a hormone secreted in reaction to stresses. Adrenaline can trigger an irregular heartbeat, which disrupts the body s ability to ship oxygen-rich blood to the brain. Lastly, if an abuser is startled or sent into a fight-or-flight reaction, the body will release extra adrenaline. The extra-sensitivity can disturb the heart rhythm to the point of fatal cardiac arrest. 

Stress and anxiety conditions affect both physical and mental health and are also associated with a modern lifestyle and its demands. Everyone experiences stress - some is normal and essential. But to be subject to stress over a long period can be very harmful. Stress is thought to exacerbate all other clinical conditions as it acts on the sympathetic branch of the autonomic nervous system. This system is responsible for the fight or flight reactions in the body. It may cause changes to normal digestion, respiratory and cardiovascular system, poor immunity and exhaustion. Mentally it may be... 

Cells can also recover from the signal for the fight or flight reaction by taking hormones that they have released back up into themselves. Cocaine interferes with the reuptake of adrenalin by cells in the cortex of the brain, thus intensifying the effects of adrenalin and producing a sense of euphoria and (sometimes) hallucinations. Cocaine use leads to psychological dependency and can cause convulsions, respiratory failure, and death. 

Hormones control many aspects of our lives, ranging from the fight or flight reaction of adrenaline to digesting sugars (e.g., insulin). Some hormones affect our reproductive systems these hormones were first identified in nature as endocrine disrupters. Because they affect so many of our processes, it is not surprising that their toxic effects can be very diverse. 

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