Pharmacology Quiz: Do You Really Know About Drugs?

At low to medium therapeutic doses, sympathomimetic drugs are designed to selectively target specific receptors in the body. However, at high or toxic doses, these drugs can interact with and stimulate other receptors in addition to their intended targets. This can lead to unintended side effects or adverse reactions. Therefore, the statement that sympathomimetic drugs can stimulate other receptors at high or toxic doses is true.

Tamsulosin is selective for the A1a adrenergic receptor. This means that it specifically targets and binds to this receptor subtype, leading to its pharmacological effects. By selectively binding to the A1a receptor, tamsulosin can block the action of norepinephrine, a neurotransmitter, on this receptor, resulting in relaxation of smooth muscles in the prostate and bladder neck. This selective action of tamsulosin on the A1a receptor makes it a useful medication for the treatment of urinary symptoms associated with benign prostatic hyperplasia (BPH).

Timolol is a medication used to treat glaucoma, a condition characterized by increased intraocular pressure (IOP). It works by reducing the production of aqueous humor, the fluid that fills the front part of the eye. By decreasing the formation of aqueous humor, Timolol helps to lower the IOP, which is essential for managing glaucoma and preventing further damage to the optic nerve. Therefore, the statement "Timolol treats glaucoma by reducing the formation of aqueous humor and thereby lowering the IOP" is true.

G-protein coupled receptors (GPCRs) are a type of cell membrane receptor that are involved in signal transduction. They are activated by binding of ligands, such as hormones or neurotransmitters, which then triggers a cascade of intracellular signaling events. Adrenergic receptors specifically bind to the neurotransmitters epinephrine and norepinephrine, and are classified as GPCRs. This allows them to activate G-proteins, which in turn regulate various cellular processes. Therefore, the correct answer is G-protein coupled receptors.

Isoproterenol is selective for B1 and B2 receptors. These receptors are part of the beta-adrenergic receptor family. B1 receptors are mainly found in the heart and are responsible for increasing heart rate and contractility. B2 receptors are found in smooth muscle tissues, such as the bronchioles of the lungs, and their activation leads to relaxation and dilation of these muscles. Isoproterenol's selectivity for both B1 and B2 receptors makes it useful in medical treatments such as treating bradycardia or bronchospasm.

Norepinephrine is a neurotransmitter released into the neuroeffector junction. This question asks how 50% of the released norepinephrine is removed from the junction. The correct answer is that it is taken out of the junction by a neuronal uptake pump. This means that the norepinephrine is actively transported back into the neuron that released it, effectively removing it from the junction.

Norepinephrine is selective for A1, A2, and B1 receptors. These receptors are part of the adrenergic system, which is responsible for the body's response to stress and emergencies. A1 receptors are found in smooth muscles and blood vessels, causing vasoconstriction. A2 receptors are located in the brain and peripheral tissues, regulating neurotransmitter release. B1 receptors are primarily found in the heart, increasing heart rate and contractility. Therefore, norepinephrine can bind to and activate these receptors, leading to various physiological responses.

The urgency/retention is caused by contraction of the smooth muscle of the prostate pressing on the urethra. Blocking A1A by tamsulosin results in increased urine outflow.

(shudders) yuck

They are 2nd generation. Labetalol/Carvedilol are 3rd generation.

Tyramine is a naturally occurring compound found in certain foods and beverages. It is commonly associated with triggering migraines and other adverse reactions in sensitive individuals. While beer, wine, and cheese are known sources of tyramine, acidic fruits do not contain significant amounts of this compound. Therefore, acidic fruits are not a source of tyramine.

Phenylephrine is selective for A1 receptors. A1 receptors are a subtype of alpha-adrenergic receptors found in smooth muscle cells of blood vessels. Activation of A1 receptors by phenylephrine causes vasoconstriction, leading to an increase in blood pressure. This selective action on A1 receptors makes phenylephrine useful in treating conditions like hypotension and nasal congestion.

Cocaine and Imipramine are both known to inhibit the reuptake of norepinephrine, a neurotransmitter, at the neuroeffector junction. This means that they prevent the removal of norepinephrine from the synaptic cleft, leading to increased levels of norepinephrine in the brain. Therefore, the statement that cocaine and Imipramine block the removal of norepinephrine out of the neuroeffector junction is true.

Pseudoephedrine is a MIXED agonist because it works by these 2 mechanisms to increase the action of norepinephrine.

A2 is the most important receptor in the brain!! It turns off NE release. B receptors turn on NE release when stimulated.

Yohimbe or "horny goat weed" blocks A1 and is believed that it is connected with brain pathways associated with interest in sex (aphrodisiac)

used ONLY in chronic heart failure, when constant sympathetic input is hurting the heart and compromising its function further.

Labetalol and carvedilol are selective antagonists for A1, B1, and B2 receptors. Selective antagonists are drugs that specifically bind to and block the activity of certain receptors in the body. In this case, labetalol and carvedilol target A1, B1, and B2 receptors. These receptors are found in various tissues and organs, including the heart, blood vessels, and lungs. By blocking these receptors, labetalol and carvedilol can help to lower blood pressure, reduce heart rate, and relax blood vessels, making them useful in the treatment of conditions such as hypertension and heart failure.

Used to treat performance anxiety & muscle tremors in people like fine musicians or sharp shooters. It affects the movement of glucose & potassium in/out of the muscle and prevents excessive stimulation.

Reserpine affects NE uptake by blocking the transport of norepinephrine and dopamine into the storage vesicle. This means that reserpine prevents the reuptake of these neurotransmitters into the vesicles, which are responsible for storing them. As a result, the levels of norepinephrine and dopamine in the synaptic cleft are reduced, leading to decreased neurotransmission.

Clonidine is a drug that blocks the activity of adrenergic neurons. Adrenergic neurons are responsible for releasing norepinephrine, a neurotransmitter that plays a role in the sympathetic nervous system. By blocking these neurons, clonidine reduces the release of norepinephrine, leading to various effects such as lowering blood pressure and reducing anxiety. Therefore, the statement that clonidine is an adrenergic neuron blocking drug is true.

Turning off cAMP leads to LESS protein phosphorylation

B2 receptors are activated, which causes vasodilation & decrease in BP. The B1 receptors stimulate increased contractility of the heart which increases HR. The baroreceptors are also stimulated to increase HR.

Pindolol has the highest oral bioavailability among the given options. Oral bioavailability refers to the percentage of a drug that reaches the systemic circulation after oral administration. Pindolol is known to have a high oral bioavailability, meaning that a larger proportion of the drug is absorbed and reaches the bloodstream when taken orally compared to the other drugs listed (Nadolol, Atenolol, and Metoprolol). This suggests that Pindolol is more efficiently absorbed and has a higher systemic availability when taken orally.

Visine is used to treat ocular congestion by decreasing capillary permeability and contracting blood vessels. This action helps to reduce redness and swelling in the eyes, providing relief from congestion.

Adrenergic agonists are used to TREAT open angle glaucoma. Worsening of narrow angle glaucoma is an adverse event caused by stimulating A1.

Beta receptor antagonists, also known as beta blockers, work by blocking the beta receptors in the body. These receptors are found in various organs and tissues, including the heart, kidneys, and lungs. By blocking these receptors, beta blockers have several effects on the body. One of these effects is a decrease in glycogenolysis and gluconeogenesis, which refers to the breakdown of glycogen into glucose and the production of glucose from non-carbohydrate sources, respectively. This decrease in glucose production and release helps to lower blood sugar levels and can be beneficial in conditions such as diabetes.

Amphetamine, Phentermine, and methylphenidate are drugs that release norepinephrine. These drugs belong to a class called sympathomimetic amines, which stimulate the release of norepinephrine from nerve endings. Norepinephrine is a neurotransmitter that plays a role in regulating various physiological processes, including attention, alertness, and mood. By increasing the release of norepinephrine, these drugs can have stimulant effects on the central nervous system, leading to increased wakefulness and focus.

Tachycardia is not an adverse effect of beta blockers. Beta blockers actually work to decrease heart rate, so tachycardia would not be expected as a side effect. Wheezing, CNS effects, and rebound angina are all potential adverse effects of beta blockers.

Phenylephrine would cause vasoconstriction (increased BP) but then the baroreceptors would kick in to keep the HR low.

Septic shock is primarily associated with low blood pressure. Cardiogenic shock is related to reduced work of the heart.

Amphetamine causes the neuronal uptake pump to run backwards, which leads to the pumping of neuroepinephrine (NE) into the neuroeffector junction. This occurs because amphetamine displaces NE from the vesicle, preventing its storage and causing it to be released into the junction. This results in an increased concentration of NE in the junction, leading to its effects on the neuroeffector junction.

Phentermine is used in appetite suppression by stimulating dopamine receptors in the brain. This stimulation leads to a decrease in appetite and a feeling of fullness. Additionally, phentermine releases norepinephrine (NE) in the central nervous system, which further triggers the release of dopamine. This combined action of stimulating dopamine receptors and releasing NE and dopamine helps to suppress appetite and control food cravings.

Beta blockers are used to PREVENT angina. Patient would use nitrostat for treatment.

Raynaud's is a condition that presents in the extremities, specifically the digits, with white discoloration when exposed to cold temperatures. This is due to excessive vasoconstriction in combination with plaques in the arterioles. The condition can be treated with alpha blocking drugs, such as prazosin or phenoxybenzamine. These medications help to relax and widen the blood vessels, improving blood flow and reducing symptoms.

Metyrosine is a medication that blocks the conversion of tyrosine to dopa. This is significant because dopa is a precursor to norepinephrine, a neurotransmitter involved in the stress response. By inhibiting this conversion, metyrosine reduces the production of norepinephrine, which can be beneficial in the treatment of conditions such as pheochromocytoma. Additionally, metyrosine can enter the brain and cause central nervous system (CNS) effects, further contributing to its therapeutic actions. It is important to note that while metyrosine can be used to manage symptoms, the only definitive treatment for pheochromocytoma is surgical removal of the tumor.