]> 2026-07-31T07:51:15+00:00 WBR0573 0 en α-adrenergic receptors α-adrenergic receptors may be either α1 or α2. α1-receptors have a role in vasoconstriction, pupillary dilation, and bladder sphincter muscle contraction. α2-receptors have a role in decreasing sympathetic outflow, insulin release, and lipolysis. α-adrenergic receptors are not involved in modulation of skeletal muscle function. 5-HT2 receptors 5-HT2 receptors are not part of the inhibitory pathway of the basal ganglia. 5-HT2 mediate many of the central and peripheral physiologic functions of serotonin. Nicotinic receptors Dopamine D1 receptors Dopamine D2 receptors Dopamine D2 receptors are involved in the inhibitory or indirect pathway that causes a net decrease in locomotor activity. A defect in the inhibitory pathway, such as a subthalamic nucleus lesion, results in a shift of the balance toward the excitatory pathway and increased movement, which is observed in hemiballismus, chorea, and athetosis. Pathophysiology A 68-year-old left-handed man with a past medical history of chronic stable angina and hypertension presents to the emergency department with violent involuntary movements of his right extremities for the past 3 hours. The patient explains that these attacks began suddenly and have since been repetitive and uncontrollable. Physical examination is remarkable for non-rhythmic, continuous, violent flinging motions of the right upper and lower extremities. Although a cranial CT scan is negative, an underlying small ischemic stroke is still suspected. Which of the following receptors is a significant component of the pathway involved in this patient's condition? E Neurology 2020-10-28T01:00:07Z 2459150.5417477 WBR0573