Ch 5 Central and peripheral nervous system

Which of the following drugs are sympathomimetic agents? 1. Salmeterol 2. Dopamine 3. Labetalol 4. Propranolol a. 1 and 2 only b. 2 and 3 only c. 1, 2, and 4 only d. 1, 2, 3, and 4

a. 1 and 2 only Both salmeterol and dopamine stimulate the sympathetic nervous system. Labetalol and propranolol are sympatholytic agents.

You are treating a patient for bronchospasm. Albuterol (an adrenergic bronchodilator) is the only aerosolized agent being administered at this time. What other type of aerosolized drug might you recommend? a. Anticholinergic bronchodilator b. Sympatholytic c. Both A and B d. Neither A nor B

a. Anticholinergic bronchodilator Two classes of drugs modify smooth airway muscle tone: adrenergic bronchodilators and anticholinergic bronchodilators. A sympatholytic drug would act to negate the effects of an adrenergic bronchodilator such as albuterol.

M2 receptors are present on which of the following? a. Heart, postganglionic parasympathetic nerves b. Parasympathetic ganglia, nasal submucosal glands c. Airway smooth muscle, submucosal glands d. Postganglionic cholinergic nerves, possible effect on CNS

a. Heart, postganglionic parasympathetic nerves MUSCARINIC RECEPTOR TYPE LOCATION G-PROTEIN SUBTYPE M1 Parasympathetic ganglia, nasal submucosal glands Gq M2 Heart, postganglionic parasympathetic nerves Gi M3 Airway smooth muscle, submucosal glands Gq M4 Postganglionic cholinergic nerves, possible effect on CNS, decrease in locomotion Gi M5 Possible effect on CNS Gq

Drugs that stimulate a receptor for norepinephrine or epinephrine are a. adrenergic. b. parasympathomimetic. c. parasympatholytic. d. sympathomimetic.

a. adrenergic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.

The neurotransmitter norepinephrine is terminated by the enzymes __________ and __________. a. catechol O-methyltransferase (COMT) and monoamine oxidase (MAO) b. catechol O-methyltransferase (COMT) and cholinesterase c. cholinesterase and monoamine oxidase (MAO) d. monoamine oxidase (MAO) and pseudocholinesterase

a. catechol O-methyltransferase (COMT) and monoamine oxidase (MAO) The neurotransmitter acetylcholine is terminated by the enzyme cholinesterase, and norepinephrine and sympathetic transmission are terminated by neurotransmitter reuptake into the presynaptic neuron (uptake-1) and by the enzymes catechol O-methyltransferase (COMT) and monoamine oxidase (MAO).

A drug causing stimulation of a receptor for acetylcholine is a. cholinergic. b. anticholinergic. c. adrenergic. d. parasympathomimetic.

a. cholinergic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.

An indirect-acting cholinergic agent used in the Tensilon® test is a. edrophonium. b. methacholine. c. neostigmine. d. phospholine.

a. edrophonium. Edrophonium is used in the Tensilon® test to determine whether muscle weakness is caused by overdosing with an indirect-acting cholinergic agent or undertreatment with insufficient drug. The methacholine challenge is a lung function test used to help diagnose reactive airways. Neostigmine is used to increase muscle strength in myasthenia gravis. Phospholine is an organophosphate used in insecticides (a cholinesterase reactivator) that may have lethal effects via initial stimulation and then blockade of cholinergic receptors.

The peripheral nervous system consists of which of the following? 1. Spinal cord 2. Autonomic nervous system 3. Brain 4. Somatic portion a. 1 only b. 2 and 4 only c. 1 and 3 only d. 1, 2, 3, and 4

b. 2 and 4 only The peripheral nervous system consists of sensory (afferent) neurons; somatic (motor) neurons; and the autonomic nervous system, which can be divided into parasympathetic and sympathetic branches.

In the parasympathetic branch of the nervous system, what name is given to the neurotransmitter that conducts nerve transmission at the ganglionic site? a. Cholinesterase b. Acetylcholine c. Epinephrine d. Norepinephrine

b. Acetylcholine Cholinesterase is the name given to the enzyme that inactivates acetylcholine. Acetylcholine conducts nerve transmission at ganglionic sites and at parasympathetic effector sites found at the end of postganglionic fibers. Epinephrine is a neurotransmitter similar to norepinephrine and is capable of stimulating sympathetic neuroeffector sites. Norepinephrine is generally the neurotransmitter found at sympathetic end sites (with the exception of sweat glands and the adrenal medulla, where acetylcholine is found).

What is the adrenergic effect on bronchial smooth muscle? a. Constriction b. Dilation (relaxation) c. Both d. Neither

b. Dilation (relaxation) The effect of sympathetic (adrenergic) stimulation of the bronchi is relaxation and dilation of airway diameter.

A parasympathetic effect is generally the same as which of the following? a. Antimuscarinic effect b. Muscarinic effect c. Parasympatholytic effect d. Anticholinergic effect

b. Muscarinic effect An antimuscarinic effect may also be referred to as a parasympatholytic effect. Muscarine stimulates acetylcholine receptors at the parasympathetic terminal sites. A parasympatholytic effect would also be known as an antimuscarinic effect and an anticholinergic effect.

M1 receptors are present on which of the following? a. Heart, postganglionic parasympathetic nerves b. Parasympathetic ganglia, nasal submucosal glands c. Airway smooth muscle, submucosal glands d. Postganglionic cholinergic nerves, possible effect on CNS

b. Parasympathetic ganglia, nasal submucosal glands. MUSCARINIC RECEPTOR TYPE LOCATION G-PROTEIN SUBTYPE M1 Parasympathetic ganglia, nasal submucosal glands Gq M2 Heart, postganglionic parasympathetic nerves Gi M3 Airway smooth muscle, submucosal glands Gq M4 Postganglionic cholinergic nerves, possible effect on CNS, decrease in locomotion Gi M5 Possible effect on CNS Gq

Your patient has bradycardia. Which type of drug do you recommend? a. Sympatholytic b. Sympathomimetic c. Parasympathomimetic d. Both A and C

b. Sympathomimetic A sympatholytic drug would work to block the "fight or flight" response and prevent an increase in heart rate. A sympathomimetic drug would induce a "fight or flight" response and cause an increase in heart rate. A parasympathomimetic response would involve slowing the rate of sinoatrial (SA) node conduction and decreasing atrioventricular (AV) node conduction.

You administer an inhaled bronchodilator that is known to have adrenergic side effects. What cardiovascular clinical effect should you watch for in your patient? a. Bradycardia b. Tachycardia c. Bradypnea d. Tachypnea

b. Tachycardia The adrenergic effect on the heart is excitatory, leading to an increase in heart rate. The muscles of respiration are under somatic control.

Which portion of the nervous system is manipulated by neuromuscular blocking agents, to induce paralysis in surgical procedures or during mechanical ventilation? a. The parasympathetic branch of the autonomic nervous branch b. The somatic portions of the motor branch c. The sensory branch of the peripheral nervous system d. The spinal cord

b. The somatic portions of the motor branch The sensory branch of the nervous system consists of afferent neurons from heat, light, pressure, and pain receptors in the periphery to the CNS. The somatic portion (or motor branch) of the nervous system is under voluntary, conscious control and innervates skeletal muscle for motor actions such as lifting, walking, or breathing. This portion of the nervous system is manipulated by neuromuscular blocking agents, to induce paralysis in surgical procedures or during mechanical ventilation. The autonomic nervous system is the involuntary, unconscious control mechanism of the body, sometimes said to control vegetative or visceral functions.

Drugs that block a receptor for acetylcholine are a. cholinergic. b. anticholinergic. c. adrenergic. d. parasympathomimetic.

b. anticholinergic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.

A direct-acting cholinergic agent often used in bronchial challenge tests to assess the degree of airway activity is a. edrophonium. b. methacholine. c. neostigmine. d. phospholine.

b. methacholine. Edrophonium is used in the Tensilon® test to determine whether muscle weakness is caused by overdosing with an indirect-acting cholinergic agent or undertreatment with insufficient drug. The methacholine challenge is a lung function test used to help diagnose reactive airways. Neostigmine is used to increase muscle strength in patients with myasthenia gravis. Phospholine is an organophosphate used in insecticides (a cholinesterase reactivator) that may have lethal effects via initial stimulation and then blockade of cholinergic receptors.

Agents blocking or inhibiting the effects of the parasympathetic nervous system are a. cholinergic. b. parasympatholytic. c. adrenergic. d. parasympathomimetic.

b. parasympatholytic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.

The stimulation of which receptor sites produces bronchial smooth muscle relaxation? a. β1 b. β2 c. α d. β1 and β2

b. β2 Stimulation of β1 receptors increases the force and rate of cardiac contraction. Stimulation of β2 receptors relaxes bronchial smooth muscle as well as the vascular beds of skeletal muscle. Stimulation of α receptors results in the vasoconstriction of peripheral blood vessels.

M3 receptors are present on which of the following? a. Heart, postganglionic parasympathetic nerves b. Parasympathetic ganglia, nasal submucosal glands c. Airway smooth muscle, submucosal glands d. Postganglionic cholinergic nerves, possible effect on CNS

c. Airway smooth muscle, submucosal glands MUSCARINIC RECEPTOR TYPE LOCATION G-PROTEIN SUBTYPE M1 Parasympathetic ganglia, nasal submucosal glands Gq M2 Heart, postganglionic parasympathetic nerves Gi M3 Airway smooth muscle, submucosal glands Gq M4 Postganglionic cholinergic nerves, possible effect on CNS, decrease in locomotion Gi M5 Possible effect on CNS Gq

Means by which nerve impulses are conducted include which of the following? a. Electrical b. Chemical c. Both A and B d. Neither A nor B

c. Both A and B Nerve impulses are conducted by both electrical and chemical means; the chemical portion of nerve transmission is referred to as a neurotransmitter.

Following administration of a dose of atropine to your patient, which of the following effects are not likely to occur? a. Dry mouth b. Decreased mucus production c. Bronchial constriction d. Increased heart rate

c. Bronchial constriction As a parasympatholytic agent, atropine blocks salivary secretion and causes dry mouth. Atropine also blocks the parasympathetically maintained basal tone of bronchial smooth muscle and would produce an expected relaxation of bronchial smooth muscle. Atropine has a parasympatholytic effect on the mucous glands, decreasing mucus production, and blocks vagal innervation of the heart to produce an increased heart rate.

How is the neurotransmitter acetylcholine inactivated at the parasympathetic terminal receptor site? a. By the enzyme catechol O-methyltransferase (COMT) b. By the reuptake process c. By the enzyme cholinesterase d. By the enzyme monoamine oxidase (MAO)

c. By the enzyme cholinesterase The enzymes COMT and MAO inactivate catecholamines such as epinephrine. The reuptake process terminates norepinephrine and sympathetic transmission. Cholinesterase inactivates the neurotransmitter acetylcholine at the parasympathetic terminal receptor site.

You are treating a patient for motion sickness with the drug dimenhydrinate (Dramamine®). What possible side effect may the patient experience when taking this drug? a. Tachycardia b. Insomnia c. Dry mouth d. None of the above

c. Dry mouth The anticholinergic (antimuscarinic) effect on the vestibular system can inhibit motion sickness. Scopolamine was used for this, and antihistamine drugs such as dimenhydrinate (Dramamine®) that have anticholinergic effects are commonly used to prevent motion sickness. The dry mouth and drowsiness that also occur with a drug such as dimenhydrinate are typical antimuscarinic effects.

You are treating an asthmatic who also happens to be taking propranolol (a β blocker) for a history of cardiac arrhythmias. What type of effect would you expect albuterol to have on this patient? a. Antagonistic effect b. Synergistic effect c. Little or no effect d. Additive effect

c. Little or no effect As a β blocker, propranolol would prevent albuterol (a β agonist) from inducing the desired effect of bronchodilation. Propranolol and albuterol are not synergistic drugs and actually compete for the same receptor sites.

The somatic portion of the nervous system controls which of the following? a. Heart muscle b. Glandular secretion c. Skeletal muscle d. Smooth airway muscle

c. Skeletal muscle Heart muscle is under autonomic control. Glandular secretion and smooth airway muscle are controlled by the autonomic nervous system. Skeletal muscle (used for such motor actions as lifting, walking, and breathing) is under conscious control by the somatic portion of the nervous system.

Nicotine is capable of stimulating a. sympathetic receptors only. b. parasympathetic autonomic cholinergic receptors only. c. both sympathetic and parasympathetic autonomic cholinergic receptors. d. neither sympathetic nor parasympathetic autonomic cholinergic receptors.

c. both sympathetic and parasympathetic autonomic cholinergic receptors. Nicotine, a substance in tobacco products, stimulates acetylcholine (cholinergic) receptors at autonomic ganglia (both parasympathetic and sympathetic) and at skeletal muscle sites. The practical effects of such stimulation include increased blood pressure and skeletal muscle tremors.

The two major control systems in the body are a. the brain and spinal cord. b. the brain and nervous system. c. the nervous system and the endocrine system. d. the brain and the endocrine system.

c. the nervous system and the endocrine system. There are two major control systems in the body: the nervous system and the endocrine system. Both systems of control can be manipulated by drug therapy, which either mimics or blocks the usual action of the control system, to produce or inhibit physiologic effects.

Muscarinic receptors are found in which of the following? 1. Exocrine glands 2. Cardiac muscle 3. Smooth muscle 4. The gastrointestinal tract a. 1 and 2 only b. 2 and 4 only c. 1, 2, and 3 only d. 1, 2, 3, and 4

d. 1, 2, 3, and 4 Muscarinic receptors are found in exocrine glands, cardiac muscle, and smooth muscle of the gastrointestinal tract.

Your patient is accidentally given a large dose of a parasympathomimetic drug. What side effects of parasympathetic overstimulation do you expect to see? 1. Salivation 2. Lacrimation 3. Urination 4. Defecation a. 1 only b. 1 and 2 only c. 1, 2, and 3 only d. 1, 2, 3, and 4

d. 1, 2, 3, and 4 Overstimulation of the parasympathetic branch would render the body incapable of violent action and would result in what is termed the SLUD syndrome: salivation, lacrimation, urination, and defecation.

After administering a sympathomimetic drug to your patient, in what areas would you expect to see an upward trend? 1. Heart rate 2. Blood pressure 3. Blood glucose a. 1 only b. 1 and 2 only c. 1 and 3 only d. 1, 2, and 3

d. 1, 2, and 3 The sympathetic branch reacts as a general alarm ("fight or flight") system. As the organism prepares for maximal physical exertion, heart rate and blood pressure increase, blood flow shifts from the periphery to muscles and the heart, blood glucose increases, and bronchi dilate.

Branches of the nervous system, which can cause relaxation of airway smooth muscle, include which of the following? 1. Sympathetic nerves 2. Parasympathetic nerves 3. Nonadrenergic, noncholinergic (NANC) inhibitory nerves a. 1 only b. 2 only c. 1 and 2 only d. 1, 2, and 3

d. 1, 2, and 3 There is evidence of a branch of nerves that are neither parasympathetic (cholinergic) nor sympathetic (adrenergic), which can cause relaxation of airway smooth muscle. These nerves have been termed nonadrenergic, noncholinergic (NANC) inhibitory nerves. They are also referred to as simply nonadrenergic inhibitory nerves because adrenergic activity relaxes airway smooth muscle, and this is an additional but nonadrenergic neural method of relaxing such smooth muscle.

As a practitioner, you would expect which parts of the physical examination to be affected by a dose of atropine or other parasympatholytic agent? a. Gastrointestinal examination b. Neurologic examination c. Cardiac examination d. All of the above

d. All of the above Atropine decreases the tone and mobility of the gastrointestinal tract and causes pupillary dilation (mydriasis), which could lead an unknowing practitioner to suspect head injury, brain infarct, or some other type of detrimental process. Atropine increases the heart rate by blocking vagal innervation and may cause a patient to present with drug-induced tachycardia.

Epinephrine stimulates which of the following receptor sites? a. α b. β1 c. β2 d. All of the above

d. All of the above Epinephrine stimulates α and β sites equally.

A patient is experiencing changes in heart rate and pupillary response to light. What division of the nervous system is responsible for these changes? a. Central nervous system b. Somatic neurons c. Sensory neurons d. Autonomic nervous system

d. Autonomic nervous system The autonomic nervous system is the involuntary, unconscious control mechanism of the body, sometimes said to control vegetative or visceral functions. The autonomic nervous system regulates heart rate, pupillary dilation and contraction, glandular secretion such as salivation, and smooth muscle in blood vessels and the airway.

Which type of impulse travels from the brain to the neuroeffector sites? a. Afferent b. Reflex c. Ganglionic d. Efferent

d. Efferent Afferent nerves carry impulses from the periphery to the cord. Somatic reflex arcs travel from the periphery and back. Ganglionic is a term used to describe agents that are anticholinergic in nature. Efferent impulses travel from the brain and spinal cord out to the various neuroeffector sites.

Agents causing stimulation of the parasympathetic nervous system are a. cholinergic. b. anticholinergic. c. adrenergic. d. parasympathomimetic.

d. parasympathomimetic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.

Agents blocking or inhibiting the effect of the sympathetic nervous system are a. anticholinergic. b. adrenergic. c. parasympatholytic. d. sympatholytic.

d. sympatholytic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.

Agents causing stimulation of the sympathetic nervous system are a. adrenergic. b. parasympathomimetic. c. parasympatholytic. d. sympathomimetic.

d. sympathomimetic. The following terms are based on the anatomy of the nerve fibers, to describe stimulation or inhibition: parasympathomimetic, an agent causing stimulation of the parasympathetic nervous system sites; sympathomimetic, an agent causing stimulation of the sympathetic nervous system; cholinergic (cholinomimetic), a drug causing stimulation of a receptor for acetylcholine; anticholinergic, a drug blocking a receptor for acetylcholine; adrenergic (adrenomimetic), a drug stimulating a receptor for norepinephrine or epinephrine; antiadrenergic, a drug blocking a receptor for norepinephrine or epinephrine; cholinoceptor, an alternative term for cholinergic receptor; adrenoceptor, an alternative term for adrenergic receptor; sympatholytic, an agent blocking or inhibiting the effect of the sympathetic nervous system.