Regarding GABA, which statement is false?

Correct Answer: A

Rationale: The correct answer is A) Receptor blockers have anticonvulsant activity. This statement is false because GABA receptor blockers actually decrease the inhibitory effects of GABA, leading to increased neuronal excitability. Anticonvulsant activity is typically associated with drugs that enhance GABAergic transmission, not block it. Option B) Is found in high concentrations in the basal ganglia is true. GABA is indeed found in high concentrations in the basal ganglia, where it plays a crucial role in motor control and movement regulation. Option C) Concentrations in the basal ganglia are abnormally low in Huntington's chorea is also true. In Huntington's chorea, there is a decrease in GABA levels in the basal ganglia, contributing to the motor symptoms seen in this condition. Option D) Metabolism is inhibited by sodium valproate is true. Sodium valproate is known to inhibit the metabolism of GABA, leading to increased levels of this neurotransmitter in the brain. Educationally, understanding the role of GABA in the central nervous system is crucial for healthcare professionals, especially when managing conditions like epilepsy, movement disorders, and mood disorders. Knowing how drugs affect GABAergic transmission can help in selecting appropriate treatment options and understanding the underlying mechanisms of various neurological conditions.

Correct Answer: D

Rationale: In this scenario, the correct answer is D) Tamsulosin. Tamsulosin is a selective alpha-1 blocker that specifically targets the alpha-1 receptors in the prostate, leading to relaxation of smooth muscle in the bladder neck and prostate, which helps improve urinary flow and reduce symptoms of benign prostatic hyperplasia (BPH) like a weak stream and nocturia. A) Alfuzosin, B) Doxazosin, and C) Prazosin are also alpha-1 blockers used in BPH treatment, but they are less selective for the alpha-1 receptors in the prostate compared to Tamsulosin. This reduced selectivity can lead to more side effects like dizziness, low blood pressure, and fatigue, which the patient in this case wants to avoid due to sensitivity to medication side effects. Educationally, this question assesses the candidate's understanding of the pharmacological treatment of BPH and the importance of selecting medications with specific receptor selectivity to minimize side effects, especially in elderly patients who may be more prone to adverse reactions. Understanding the rationale behind choosing Tamsulosin over other alpha-1 blockers reinforces the importance of individualizing treatment based on a patient's specific needs and characteristics.

Correct Answer: C

Rationale: The correct answer is C) Retroperitoneal fibrosis. In this scenario, the patient's bilateral hydronephrosis and elevated serum creatinine are most likely due to retroperitoneal fibrosis caused by the bromocriptine. Retroperitoneal fibrosis is a known adverse effect of bromocriptine, a central nervous system stimulant used in Parkinson's disease. This condition results from the development of fibrous tissue in the retroperitoneal space, leading to compression of nearby structures, including the ureters, causing hydronephrosis and renal impairment. Option A) Drug toxicity is not the best choice because it does not specifically address the mechanism of action leading to the renal findings in this case. Renal artery stenosis (Option B) and renal vein thrombosis (Option D) are less likely as they typically present with different clinical features and are not commonly associated with bromocriptine use in Parkinson's disease. Educationally, understanding the potential side effects and adverse reactions of medications used in neurological conditions like Parkinson's disease is crucial for healthcare professionals. This case highlights the importance of monitoring patients for rare but serious complications associated with central nervous system stimulants, ensuring early detection and management to prevent significant harm.

Correct Answer: A

Rationale: The correct answer is A) Contains a domain that passes through the cell membrane seven times. Explanation: β2-receptors are G protein-coupled receptors located on the cell membrane. They have seven transmembrane domains that allow them to interact with intracellular G proteins when activated by ligands like epinephrine. This interaction initiates a signaling cascade that leads to bronchodilation in the case of β2-receptors in bronchial smooth muscle. Why other options are wrong: B) Forms a dimer and autophosphorylates intracytoplasmic residues - This describes receptor tyrosine kinases, not G protein-coupled receptors like β2-receptors. C) Ligand-gated chloride channel - This describes ligand-gated ion channels, not G protein-coupled receptors like β2-receptors. D) Physically attached to smooth endoplasmic reticulum causing release of intracellular calcium stores - This describes calcium channels on the endoplasmic reticulum, not β2-receptors. Educational context: Understanding the structure and function of different receptor types is crucial in pharmacology and medicine. Knowing how drugs like epinephrine interact with specific receptors helps healthcare providers make informed decisions in treating conditions like anaphylaxis. This knowledge is essential for nursing practice, especially in emergency situations where quick and accurate interventions are critical for patient outcomes.

Correct Answer: A

Rationale: The correct answer is A) Diarrhea. The woman's smoking habit of one pack per day can lead to the exacerbation of her chronic irritable bowel syndrome symptoms, particularly diarrhea. Nicotine in cigarettes can stimulate the bowel movements and increase gut motility, worsening diarrhea in individuals with irritable bowel syndrome. Option B) Muscle aches is incorrect because smoking is not directly linked to causing muscle aches in irritable bowel syndrome. Option C) Right lower quadrant pain and Option D) Right upper quadrant pain are incorrect as they are not typically associated with irritable bowel syndrome, especially in the context of smoking exacerbating symptoms. Educational Context: Understanding the potential effects of smoking on irritable bowel syndrome symptoms is crucial for healthcare providers to effectively manage and treat patients. Educating patients on the negative impact of smoking on gastrointestinal health can aid in symptom management and overall well-being. Health promotion strategies should include smoking cessation interventions to improve the outcomes for patients with irritable bowel syndrome.