ATI Pharmacology Proctored 2023 Retake 2 Exam

ATI PHARMACOLOGY PROCTORED 2023 RETAKE 2 EXAM 1. A patient with hypertension is prescribed lisinopril, an ACE inhibitor. What is the main mechanism of action of this drug? A) It blocks the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion. B) It inhibits the enzyme that breaks down bradykinin, increasing vasodilation and reducing blood pressure. C) It antagonizes the effects of angiotensin II at the receptor level, decreasing peripheral resistance and blood volume. D) It inhibits the renin -angiotensin -aldosterone system, decreasing sodium and water retention and lowering blood pressure. Answer: A Rationale: Lisinopril blocks the conversion of angiotensin I to angiotensin II, which is a potent vasoco nstrictor and stimulates aldosterone secretion. Aldosterone increases sodium and water reabsorption, leading to increased blood volume and pressure. By blocking this pathway, lisinopril reduces blood pressure. 2. A patient with type 2 diabetes mellitus is prescribed metformin, a biguanide. What are the main effects of this drug on glucose metabolism? A) It stimulates the release of insulin from the pancreas and increases the sensitivity of peripheral tissues to insulin. B) It inhibits the production of glu cose by the liver and reduces the absorption of glucose from the intestine. C) It activates the enzyme that converts glucose to glycogen and enhances the storage of glycogen in the liver and muscles. D) It inhibits the breakdown of glycogen to glucose and prevents the release of glucose from the liver into the bloodstream. Answer: B Rationale: Metformin lowers blood glucose levels by inhibiting gluconeogenesis (the production of glucose by the liver) and reducing the absorption of glucose from the intestine . It does not stimulate insulin secretion or affect insulin sensitivity. 3. A patient with asthma is prescribed albuterol, a beta -2 adrenergic agonist. What are the main effects of this drug on the respiratory system? A) It relaxes the smooth muscles of t he bronchi and bronchioles, increasing airway diameter and improving airflow. B) It inhibits the release of histamine and leukotrienes from mast cells, reducing inflammation and mucus production. C) It stimulates the ciliary activity and mucociliary cleara nce, enhancing the removal of secretions and foreign particles. D) It increases the production of surfactant and prevents alveolar collapse, improving gas exchange and oxygenation. Answer: A Rationale: Albuterol relaxes the smooth muscles of the bronchi and bronchioles, which are innervated by beta -2 adrenergic receptors. This results in bronchodilation, which increases airway diameter and improves airflow. Albuterol does not have anti-inflammatory or mucolytic effects. 4. A patient with rheumatoid arthr itis is prescribed methotrexate, a disease -modifying antirheumatic drug (DMARD). What is the main mechanism of action of this drug on the immune system? A) It inhibits the synthesis of purines and pyrimidines, interfering with DNA replication and cell divi sion of rapidly proliferating cells. B) It binds to and inhibits tumor necrosis factor alpha (TNF -alpha), a cytokine that mediates inflammation and tissue damage. C) It depletes folate levels, impairing the function of T cells and B cells that are involved in autoimmune reactions. D) It inhibits dihydrofolate reductase, an enzyme that converts folic acid to its active form, tetrahydrofolate. Answer: D Rationale: Methotrexate inhibits dihydrofolate reductase, which is essential for the synthesis of purines a nd pyrimidines, the building blocks of DNA. This affects rapidly dividing cells, such as T cells and B cells that are responsible for autoimmune responses. Methotrexate also reduces folate levels, which are needed for DNA synthesis. 5. A patient with depr ession is prescribed fluoxetine, a selective serotonin reuptake inhibitor (SSRI). What is the main effect of this drug on neurotransmission in the brain? A) It increases the availability of serotonin in the synaptic cleft by blocking its reuptake into pres ynaptic neurons. B) It enhances the activity of serotonin receptors on postsynaptic neurons by increasing their affinity for serotonin. C) It stimulates the synthesis of serotonin in presynaptic neurons by providing more tryptophan, its precursor. D) It pr events the degradation of serotonin in synaptic cleft by inhibiting monoamine oxidase (MAO), an enzyme that breaks down serotonin. Answer: A