Explain how the role of epigenetics may contribute to pharmacologic action
For this Discussion, review the Learning Resources and reflect on the concepts of foundational neuroscience as they might apply to your role as the psychiatric mental health nurse practitioner in prescribing medications for patients.
- Explain the agonist-to-antagonist spectrum of action of psychopharmacologic agents, including how partial and inverse agonist functionality may impact the efficacy of psychopharmacologic treatments.
- Compare and contrast the actions of g couple proteins and ion gated channels.
- Explain how the role of epigenetics may contribute to pharmacologic action.
- Explain how this information may impact the way you prescribe medications to patients. Include a specific example of a situation or case with a patient in which the psychiatric mental health nurse practitioner must be aware of the medication’s action.
******* REQUIRED READINGS/RESOURCES
-Camprodon, J. A., & Roffman, J. L. (2016). Psychiatric neuroscience: Incorporating pathophysiology into clinical case formulation. In T. A. Stern, M. Favo, T. E. Wilens, & J. F. Rosenbaum. (Eds.), Massachusetts General Hospital psychopharmacology and neurotherapeutics (pp. 1–19). Elsevier.
Neurotransmitters and Receptor Theory
Agonist-To-Antagonist Spectrum of Action of Psychopharmacologic Agents
An agonist is a chemical that fixes a receptor and activates it to yield a biological response. However, an antagonist is a group of institutions, characters, or concepts representing or stands in opposition and must be contended by the protagonist (Wager et al., 2017). In other words, the antagonist is an individual or group of persons opposing a protagonist. The agonist and antagonist’s difference is that agonist causes an action while antagonist opposes an action of the former. Inverse agonist produces a biological response opposite from that of agonist. In pharmacology, partial agonists are medications that fit themselves on a given receptor and activate them. Their efficacy is partial compared to full agonists (Camprodon & Roffman, 2016). Partial agonists can be used to activate the receptors so that they can respond to medications. Inverse agonists can be used to induce a pharmacological response of the agonist.
Actions of G-Couple Proteins and Ion Gated Channels
G couple proteins receptors, also known as &TM receptors or serpentine receptors, are part of evolutionarily-related proteins, the largest and diverse class of membrane receptors found in the eukaryotes (Meng, Kang & Zhou, 2018). The g couple proteins function as an inbox for messages in peptides, light energy, sugars, lipids, and proteins. On the other hand, ion gated channels are a group of proteins known as transmembrane ion-channel, which open to permit ions, such as sodium, calcium, potassium, or chloride, to pass through the cell membrane in response to the action of a ligand. The key difference between the two elements is that G protein-coupled receptors have a wide variety of functions, including transmitting signals from many stimuli outside the cell into the cell. However, ion gated channels are pores in the cell membrane that allow the passage of in and out of the cell. The similarity is that these two elements are fundamental in pharmacology in that they determine how humans respond to certain medications.
Impact of Epigenetics Role in Pharmacologic Action
Epigenetics is the study of how environment and behavior can cause transitions that impact the functions of one’s genes. Unlike genetics, epigenetics changes cannot alter the DNA sequence and are reversible but can change how the body sees the DNA sequence. The role of epigenetics may have a huge contribution to pharmacologic action, especially pharmacokinetics or drug metabolism. The changes in the expression of enzymes involved in drug metabolism can impact the pharmacokinetic process. For instance, Mestre-Fos et al. (2018) report that minRNAs can help medication behavior by changing the drug’s distribution of metabolism.
Impact of the Information in Drug Prescription
Epigenetic alterations are fundamental in both disease and normal state of a patient. The alterations include phosphorylation, acetylation, methylation, and ubiquitylation of the histone chromatin and the DNA (Mestre-Fos et al., 2018). Few patients respond to standard therapies because of various gene alterations in their cells. Therefore, when prescribing medications, a caregiver should evaluate the patient’s epigenetics. In mental health, epigenetics can determine the side effects of medications and identify new pharmaceutical targets for treatment (Camprodon & Roffman, 2016). For instance, a drug such as aripiprazole can have an epigenetic effect on a patient’s gene. Hence, when prescribing it, psychiatric mental health should be aware of its action.
Camprodon, J. A., & Roffman, J. L. (2016). Psychiatric neuroscience: Incorporating pathophysiology into clinical case formulation. In T. A. Stern, M. Favo, T. E. Wilens, & J. F. Rosenbaum. (Eds.), Massachusetts General Hospital psychopharmacology and neurotherapeutics (pp. 1–19). Elsevier.
Meng, X. Y., Kang, S. G., & Zhou, R. (2018). Molecular mechanism of phosphoinositides’ specificity for the inwardly rectifying potassium channel Kir2. 2. Chemical science, 9(44), 8352-8362. DOI: 10.1039/C8SC01284A
Mestre-Fos, S., Penev, P. I., Suttapitugsakul, S., Ito, C., Petrov, A. S., Wartell, R. M., … & Williams, L. D. (2018). Dynamic G-quadruplexes on the surface of the human ribosome. bioRxiv, 435594. doi: 10.1016/j.jmb.2019.03.010
Wager, T. T., Chappie, T., Horton, D., Chandrasekaran, R. Y., Samas, B., Dunn-Sims, E. R., … & Schmidt, C. J. (2017). Dopamine D3/D2 receptor antagonist PF-4363467 attenuates opioid drug-seeking behavior without concomitant D2 side effects. ACS chemical neuroscience, 8(1), 165-177. https://doi.org/10.1021/acschemneuro.6b00297