The spouse of a patient newly diagnosed with mild, unilateral symptoms of Parkinson disease (PD) asks the nurse what, besides medication, can be done to manage the disease. The nurse will:

A) Central nervous system (CNS), memory, and cognition: Myasthenia gravis (MG) primarily affects the neuromuscular junction, causing muscle weakness, not directly the central nervous system. While cognitive function may be affected in some patients due to fatigue or medication side effects, it is not the main system affected by MG.

B) Cardiovascular system and postural muscles: Myasthenia gravis primarily affects skeletal muscles, especially those responsible for voluntary movements like facial muscles, swallowing, and respiratory muscles. While MG can lead to general weakness, it does not typically affect the cardiovascular system directly.

C) Respiratory system and facial muscles: This is the correct answer. Myasthenia gravis primarily affects the voluntary muscles, particularly those controlling eye movements, facial expressions, swallowing, and breathing. The respiratory system is vulnerable due to weakness of the diaphragm and intercostal muscles, which can lead to respiratory distress in severe cases. Facial muscles are commonly affected, leading to symptoms like ptosis (drooping eyelids) and difficulty smiling or speaking.

D) Gastrointestinal system (GI) and lower extremity muscles: Although myasthenia gravis can cause generalized muscle weakness, it is not typically associated with the gastrointestinal system. The primary impact is on the voluntary muscles, such as those in the face, throat, and respiratory system. Lower extremity muscles can be affected, but the respiratory and facial muscles are more commonly involved.

A) Sweating: Sweating is a function of the sympathetic nervous system, not the parasympathetic nervous system. The sympathetic nervous system is responsible for the "fight or flight" response, which includes activating sweat glands. The parasympathetic system, in contrast, is more involved in "rest and digest" functions.

B) Pupil dilation: Pupil dilation (mydriasis) is mediated by the sympathetic nervous system through the activation of alpha-1 adrenergic receptors. The parasympathetic system causes pupil constriction (miosis) by stimulating muscarinic receptors in the eye, which is the opposite of pupil dilation.

C) Vasoconstriction: Vasoconstriction (narrowing of blood vessels) is generally a
function of the sympathetic nervous system, which releases norepinephrine to constrict blood vessels and increase blood pressure. The parasympathetic system typically causes vasodilation (widening of blood vessels) to promote relaxation and decreased blood pressure.

D) Anabolism: Anabolism refers to the metabolic processes that build up molecules and store energy, such as protein synthesis, cell growth, and energy storage. This is primarily mediated by the parasympathetic nervous system, which is involved in "rest and digest" functions. The parasympathetic system promotes activities that support energy conservation, digestion, and tissue repair, all of which support anabolic processes.