Drugs on Stress Perception and Stress Adaptation

¶ … Drugs on Stress Perception and Stress Adaptation

This paper addresses the dual effects of drugs and stress: drugs may change the perception of stress or activities under stress, and drugs affect adaptation to stress. The brain under stress functions in a highly active, yet limited capacity. This "flight or fight" mechanism is referred to as "stressors" and is divided into three categories: external conditions that result in pain or discomfort, internal homeostatic disturbances, and learned or associative responses to the perception of impending endangerment, pain and discomfort, known as "psychological stress." Drugs may change how the brain works to either effect a more stressful, restricted situation or to allow for more flexibility in its activity.

Stress may make a person alert, but it also restricts the activities of the mind and body. A study done at Ohio State University finds that taking a common drug, a beta-blocker sold as Inderal and by other generic names, restores the mental flexibility that disappears when stress takes over the brain. Inderal restores problem-solving ability in people under stress. The findings were reported in 2005 at the Society for Neuroscience in Washington. A group of people made about 40% fewer correct answers on a test after watching a stressful movie than they did after watching a comedy film, yet memory was not affected.

This suggests that stress affects mental problem-solving functions by activating a specific part of the brain and beta blockers slow this process. Other-stress-inducing tests produced the same results. Test scores were consistently worse following stressful situations than after stress-free situations, even when it was the same group of people taking both tests. But when these subjects took 40 milligrams of Inderal before the stressful situation, test scores turned out as well as when they were not under stress. Inderal, a beta-blocker, evidently slows the neuroendocrine system and suppresses the release of stress-related hormones normally produced in a stressful situation (DeNoon, para. 1-12).

Mind-altering drugs are affected by stress in sometimes unpredictable ways. Overpowering noise creates stress, and this stress enhances "recreational" drugs. As many nightclub fans know, loud music enhances the effects of taking the drug ecstasy. In a study in Italy with results appearing in the journal BMC Neuroscience, Class -- a drugs were given to laboratory rats and the rats were exposed to rave music at the decibel level commonly found in clubs. Researchers found that not only does the loud noise prolong the effects of ecstasy by up to five days, but noise and ecstasy together may damage nerve pathways in the brain. They found, by measuring electrical activity in the rodents' brains, that without the music, brain activity returned to normal in just one day. Dr. Michelangelo Iannone, from the Institute of Neurological Science in Catanzaro, Italy, stressed the potential danger of substances popularly accepted as safe owing to their supposedly short-term effects (Tait, para. 12).

Drugs can alter perceptions of stress. Psychoactive drugs affect the connections between neurons in the brain - synapses - where chemical messages jump from one neuron to the next. Drugs interfere with this transmission, affecting perception of what is happening. Brain activity depends on electrical impulses traveling along nerve cells with chemical messages jumping between them. An electric spark triggers a neuron to release a chemical at a neurotransmitter, which affects the synapse, causing it to lock to a second neuron, causing the second neuron to fire. When the first neuron reabsorbs the chemical, the firing stops. Mood-altering drugs, such as ecstasy and Prozac, stop the neurotransmitter from reabsorbing serotonin, creating a concentration in the synapse and aiding the firing process. Serotonin levels are strongly linked with mood and emotion, with resulting euphoria (Maes, p. 313).

Drugs used to medicate illnesses may be suppressed or enhanced by stress, as immune systems are very much affected by stress, depending on the nature of the stressor and immune variables. There is a possibility that psychological stress may affect the production of pro-inflammatory and immunoregulatory cytokines, which in turn affect homeostatic responses to stress and stress-induced anxiety (Maes, et al. p. 313).

The effects of stress on drugs such as interleukin (IL)-1 receptor ® antagonist (a), soluble (s) IL-2R, sIL-6R, soluble glycoprotein 130 (sgp130) have been studied. In one study stress, such as the stress students undergo when they are taking examinations, has been measured by scores on the PSS, and the STAI, and compared with immune-inflammatory variables and levels of serum cortisol to find out if there is a relationship between serum levels and stress. It was found that academic exam stress caused significant increases in PSS and STAI scores, which were related to high levels of serum, significantly more so in males than females, who only had an increase in serum sgp130 when taking birth control drugs. Males were found to have significantly more serum sCD8. The results suggest that psychological stress induces immune-inflammatory changes with complex regulatory responses in IL-6 signaling, decreased anti-inflammatory capacity of serum and interactions with T-cell and monocytic activation. The results of this study also suggest that sex hormones may modify stress-induced immune-inflammatory responses (Song et al. p. 293).

Anxiolytic drugs of the benzodiazepine class and other drugs that affect catecholamine, GABAA, histamine and serotonin receptors, alter the stress response and regulate stress hormone secretion. It has been shown that exposure to hostile conditions induces lowered immune system and cardiovascular responses, as well as neural circuits and neurotransmitter system responses. It also initiates the secretion of several hormones, including corticosterone/cortisol, catecholamines, prolactin, oxytocin, and renin, as part of the survival mechanism (Van de Kar, p. 1). In each of these the three manifestations of stress, external, internal and psychological "stressors," there are hormones released in response to the stressors referred to as stress hormones, which are regulated by neural circuits from hypothalamic neurons that are the final output toward the pituitary gland and the kidneys. The forebrain has circuits mediating neuroendocrine responses to stressors and emphasizing neuroendocrine systems that have previously received little attention as stress-sensitive hormones: renin, oxytocin, and prolactin. Anxiolytic drugs of the benzodiazepine class and other drugs, alter the stress response and stress hormone secretion (Van de Kar, p. 1).

Steven Harris, a theoretician on brain activity, believes that any medication of the brain is ultimately damaging and creates stress and damage to the delicate pathways in the brain. Medications as they now exist, cause increased stress to the system. The current model of targeting a symptom, while ignoring the side effects that may be more damaging, he believes, is wrong. Drugs, as far as Harris is concerned, create stress, eventual damage and ultimately decrease brain function. (Harris, para. 5).

Conclusion

While studies have been consistent in showing that medications have an effect on the brain under stress, stress perception may be altered by circuitously avoiding the effects of normal neurotransmissions by inducing the ability maintain serotonin, such as in ecstasy and Prozac. Stress may be adapted to by the use of other drugs, such as Inderal, allowing the body to function as it would normally would under stress-free situations, by altering the response to stress in the brain. However, it has always been noted that there are variables, such as hormones, gender and newly discovered neuroendocrine systems that respond to stressors that affect the effect of drugs in sometimes predictable ways.