Pharmacodynamics of Serotonin. Emphasis on 5HT-3 Antagonists and SSRI Medication (II)


5-HT4 receptors are a G-protein-coupled family of re-ceptors coupled with Gs protein that stimulates the pro-duction of the intracellular signaling molecule cAMP. It has two isoforms (5-HT4S and 5-HT4L), differing in the length and sequence of their C-termini[1]. 5-HT4 are present both in the central nervous system and peripheral tissues
in the brain, are found mostly in basal ganglia and the hippocampus[2]. In the periphery, 5HT4 play an important role in the functioning of gastrointestinal tract, urinary bladder, heart and adrenal gland. Gastrointestinal 5-HT4 receptors potentiate peristalsis, and electrolyte secretion. In the urinary bladder, acti-vation of 5-HT4 receptors modulates cholinergic and purinergic transmission. Stimulation of atrial 5-HT4 receptors produces tachycardia and arrhythmias. In the adrenal gland, activation of 5-HT4 receptors releases cortisol, aldosterone and corticosterone[3]. […]