Dopamine Receptor Subtypes and Arousal

Abstract

Publisher Summary The study of events induced by centrally acting dopaminergic (DAergic) agents is a classic means of investigating the pharmacology and function of DA within the central nervous system (CNS). This chapter focuses on the activity of selective agonists for D-1 and D-2 receptors. The series of experiments demonstrates that DA receptor systems, especially the D-1 subtype, are primarily involved in the generation of arousal in laboratory animals. From the data, it appears that both D- 1 and D-2 receptors, when stimulated, can influence to different extents this physiological event. However, of the two receptors, D-1 seems more concerned with the generation of cortical and behavioral arousal. At the cellular level, the differential function in arousal process between D-1 and D-2 receptors might well depend on the different cascade of events that are initiated by the stimulation of each receptor site. The formation of the second messenger cAMP and the activation of the polyphosphoinositide system could certainly be responsible for differences in the ultimate biological response. In addition, it is well known that the DAergic system may be intimately related with the noradrenergic system in the control of behavior. Experimental and theoretical reviews have proposed that multicenter anatomical systems with multiple neurochemical signatures are involved in the elaboration of the sleep-waking states.