Selective Serotonin Reuptake Inhibitors (SSRIs) Paper Example

Introduction

Major depressive disorder (MDD), also know depression is a psychiatric condition which causes severe mood changes, feeling of sadness and loss of interest in activities that one previously found fun to do leading to normal life impairment. Depression is more than feeling "blue" or "down in the dumps" for a few days because people experiencing MDD are completely incapacitated to perform their normal daily activities. A major depressive disorder is a severe mental condition that involves the brain function impairment, and it is triggered by extreme pressure at work, school, relationship stress and losing a loved one which are factors that cause depression (Villanueva, 2013). This paper will research on major depressive disorder epidemiology, physiology, pathophysiology, and treatment using literature review.

Is your time best spent reading someone else’s essay? Get a 100% original essay FROM A CERTIFIED WRITER!

Save 25%

Epidemiology

According to National Institute of Mental Health major depressive disorder is a common mental problem in the United States of America that affects 16.2 million adults which amount to 6.7 percent of the entire adult's population in the country with most of the affected experiencing the condition episode in the past year. Approximately 300 million people around the world suffer from major depressive disorder according to the World Health Organization, and the psychiatric condition is associated with a considerable number of morbidity and disability cases. This epidemiology shows that major depressive disorder remains a significant health problem and there is a need for further studies to understand the disease and create methods that can be used to treat and control its prevalence.

Physiology

The physiological processes that are affected by major depressive disorder is the brain's neurological processes in the brain. The brain is the powerhouse of human thinking processes and most psychiatric conditions interfere with the hippocampus, amygdala and the prefrontal cortex of the brain. The physiology of the major depressive disorder is still unknown despite decades of research on the mental condition (Villanueva, 2013). Brain simulations and neuropsychiatric studies have established that the localization of MDD is in the brain by interfering with the function of serotonin production in the brain stem which is responsible for sending messages to the brain for processing and commands to the rest body organs due to the dysfunction of the stress hormones released in the hippocampus. The cortical and the subcortical limbic regions of the brain in various studies on patients with depression have indicated that they are compromised (Villanueva, 2013). The brain stem which is responsible for producing neurotransmitters is also affected. This physiology suggests that the body organ that is primarily affected in patients with the major depressive disorder is the brain which is the reason behind the erratic behavior and confusion of the patients. The brain cells which produce neurotransmitters when they are affected the movement of messages in the neurons is impaired which results in the incapacitation of the brain (Villanueva, 2013). This physiology shows that MDD is caused by multiple brain malfunction especially the hippocampus that fails to regulate cortisol production.

Pathophysiology

Pathophysiology refers to the processes that cause the major depressive disorder. The regulation of the stress hormones by the hippocampus plays a significant role in regulating moods. The hippocampus which regulates the production of cortisol, as well as memories, is the brain part that is affected which results in major depressive disorder. When the body is exposed to mental stress, it releases cortisol, but in excess, the cortisol in the brain can lead to a chemical imbalance in the brain which reduces the production of serotonin a neurotransmitter used in the movement of the messages in the neurons. Serotonin is produced in the hippocampus, and people with the major depressive disorder are unable to control their moods due to the interaction of different levels of serotonin and cortisol from the hippocampus (Cowen & Browning, 2015). When the body experiences mental stress over a long period the high cortisol level affects the production of new neurons and the existing neurons shrinks which results in memory problems a problem experienced by many MDD patients. Besides, the prefrontal cortex that regulates emotions and decision generation is affected in excess cortisol which makes it difficult for the MDD patients to manage emotions. The amygdala in excess exposure to cortisol becomes enlarged and hyperactive to sensing pleasure and fear which results in the reduced ability of the brain to regulate sleep and normal activities.

Treatment

Major depressive disorder can be treated using selective serotonin uptake inhibitors which helps to reduce the impact of excessive cortisol by increasing serotonin which is a major neurotransmitter. The selective serotonin reuptake inhibitors (SSRIs) use in treating MDD can be explained by its ability to restore the chemical balance in the brain by reducing cortisol production. SSRIs are non-polar compounds that are highly selective inhibitors which inhibit serotonin reuptake (Isaac et al., 2013). MDD involves complex and many brain malfunction which occur due to the alteration of the neurotransmitters and the central nervous system. The adjustment of the presynaptic neurotransmitter function of synthesis, reuptake, metabolism, and release as well as the postsynaptic role of the neurotransmitter changes receptor, ion transportation, G-proteins and second massagers which disrupt their ability to regulate emotions (Isaac et al., 2013). Using SSRIs which are selective inhibitors of the presynaptic 5-hydroxytryptamine reuptake a transporter leads to an increase in serotonin in the synaptic cleft helps to decrease the firing rate of the serotonergic neurons by creating a negative feedback mechanism which activates the presynaptic serotonin autoreceptor (Isaac et al., 2013). The resulting neuroadaptive shifts lead to an increase in the overall serotonin released and transmitted which results in a therapeutic effect. SSRIs are very specific inhibitors and are readily absorbed from the gastrointestinal tract. The selective serotonin reuptake inhibition does not affect other neurotransmitters, and besides, SSRIs are considered less toxic compared to the other available antidepressants used to treat MDD which makes it safe (Isaac et al., 2013). It is critical to take SSRIs with food to reduce possible effects on the gastrointestinal tract because food does not reduce the level of absorption.

Conclusion

The effect of major depressive disorder on the brain is distributed to different brain regions which makes it a complex problem. MDD patients exhibit unstable behavior and emotional control which is due to the imbalance of the brain chemicals such as serotonin a neurotransmitter. The localized abnormalities are caused by the malfunction of the hippocampus which regulates memories and the release of cortisol which is a stress hormone. Prolonged exposure to stress and pressure can lead to an imbalance in the brain chemicals due to the high amount of cortisol which reduced serotonin release a major neurotransmitter. The brain chemical imbalance can be corrected using selective serotonin reuptake inhibitors which helps inhibit the presynaptic reuptake of serotonin and increase serotonin concentration in the brain which activates the presynaptic serotonin autoreceptor and results in a therapeutic effect.

References

Cowen, P. J., & Browning, M. (2015). What has serotonin to do with depression?. World Psychiatry, 14(2), 158-160.

Isaac, R., Boura-Halfon, S., Gurevitch, D., Shainskaya, A., Levkovitz, Y., & Zick, Y. (2013). Selective serotonin reuptake inhibitors (SSRIs) inhibit insulin secretion and action in pancreatic v cells. Journal of Biological Chemistry, 288(8), 5682-5693.

Villanueva, R. (2013). Neurobiology of major depressive disorder. Neural plasticity, 2013.