Jodi M Vaughn YesterdayJun 7 at 12:20am WEEK 2 MAIN POST The agonist-to-antag

Jodi M Vaughn
YesterdayJun 7 at 12:20am
WEEK 2 MAIN POST
The agonist-to-antagonist spectrum of action of psychopharmacology agents refers to the ability of drugs to modulate neurotransmitter function. An agonist activates a receptor, producing a response, while an antagonist blocks the receptor, preventing any activation. The spectrum of action ranges from full agonists, partial agonists, neutral antagonists, inverse agonists, and antagonists. Partial agonists produce a lower response at the receptor than full agonists. Inverse agonists have the opposite of an agonist effect, inducing less activity than the observed basal activity. The selection of a partial agonist or an inverse agonist may contribute to the efficacy of a psychopharmacologic treatment, given a drug’s dose-response curve (Stahl et al., 2021a). Several factors, such as an individual’s drug metabolism and genetics, can modulate any medication’s efficacy, explaining the variability in response.
In contrast to the G-coupled protein, ion channels directly regulate the concentration of ions in the cell. Upon neurotransmitter binding to the receptor, the ion channel opens in the first instance, allowing an influx of ions. The flow of ions activates the signal in the postsynaptic neuron, generating an electrical signal (Stahl et al., 2021b).
Epigenetics studies the modification of gene expression without altering the DNA sequence (Maggert, 2011). These modifications can influence gene expression, transcription, and protein synthesis, affecting various psychiatric and neurological diseases. The individual’s environment and experiences can alter brain development, gene expression, and metabolism-associated psychiatric disorders through epigenetic mechanisms. The epigenetic profile of individuals can be used to predict which drugs may be most beneficial for their given condition. Epigenetics has profound implications for pharmacology, recognizing individual patient biology, mapping distinct groups, and improving efficient, targeted therapeutic interventions.
The PMHNP should consider the pharmacologic action of medications when prescribing medication. For example, in a patient who needs an anxiolytic, a benzodiazepine such as diazepam can enhance the binding of GABA on GABA A receptors, increasing chloride current in ion channels that dampen neuronal excitability. The downside of benzodiazepines is their high risk of dependence and tolerance. As a result, the prescribing PMHNP should have a candid conversation with the patient about the risks and benefits before prescribing the medication. The PMHNP should also screen for factors such as substance abuse, which can increase dependency, and monitor the patient during drug therapy, titrating the medication down gradually to prevent withdrawal symptoms (Champion & Kameg, 2021).
References
Champion, C., & Kameg, B. (2021, March). Best practices in benzodiazepine prescribing and management in primary care. The Nurse Practitioner. https://journals.lww.com/tnpj/Fulltext/2021/03000/…
Maggert, K. A. (2011, November 29). Genetics: Polymorphisms, epigenetics, and something in between. Genetics Research International. https://www.hindawi.com/journals/gri/2012/867951/?…
Stahl, S. M., Grady, M. M., & Muntner, N. (2021a). Chapter 2: Transporters, Receptors, and Enzymes. In Stahl’s essential psychopharmacology: Neuroscientific basis and practical applications (5th ed., pp. 29–50). Cambridge University Press.
Stahl, S. M., Grady, M. M., & Muntner, N. (2021b). Chapter 3: Ion Channels. In Stahl’s essential psychopharmacology: Neuroscientific basis and practical applications (5th ed., pp. 51–76). Cambridge University Press.