Related Experiment Video

Updated: Aug 8, 2026

Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography
07:51

Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography

Published on: September 22, 2011

Serotonin-induced Na+/K+ pump stimulation in vascular smooth muscle cells. Evidence for coupling to multiple receptor

S S Navran1, G Allain, H F Garcia

  • 1Department of Medicine, Baylor College of Medicine, Houston, Texas.

The Journal of Pharmacology and Experimental Therapeutics
|January 1, 1991
PubMed

Insights

Serotonin (5-HT) stimulates the Na+/K+ pump in canine femoral artery cells via 5-HT1 and 5-HT2 receptors, involving Na+ influx and calcium. This pump activation may oppose serotonin-induced contraction.

Area of Science:

  • Vascular smooth muscle physiology
  • Cellular signaling pathways
  • Pharmacology

Background:

  • Serotonin (5-HT) is a known contractile agonist in vascular smooth muscle.
  • The role of 5-HT in regulating ion transport, specifically the Na+/K+ pump, is less understood.
  • Investigating 5-HT's effects on ion transport provides insights into vascular tone regulation.

Purpose of the Study:

  • To investigate the effect of serotonin (5-HT) on the Na+/K+ pump activity in cultured canine femoral artery vascular smooth muscle cells.
  • To elucidate the receptor subtypes (5-HT1, 5-HT2) and signaling pathways involved in 5-HT-mediated Na+/K+ pump stimulation.
  • To determine the role of Na+ influx and intracellular calcium in 5-HT's action on the Na+/K+ pump.

Main Methods:

  • Cell culture of canine femoral artery vascular smooth muscle cells.
  • Measurement of ouabain-sensitive 86Rb uptake to assess Na+/K+ pump activity.
  • Pharmacological blockade of 5-HT receptors using ketanserin and methiothepin.
  • Assessment of Na+ influx and its modulation by dimethylamiloride.
  • Use of intracellular calcium chelator BAPTA/AM.

Main Results:

  • Serotonin (5-HT) significantly stimulated ouabain-sensitive 86Rb uptake (3.6-fold), indicating Na+/K+ pump activation.
  • Both 5-HT1 and 5-HT2 receptors mediate the 5-HT-induced pump stimulation, with 5-HT1 receptors primarily responsible for the associated Na+ influx.
  • 5-HT activated a Na+ influx pathway, likely Na+/H+ exchange, and increased intracellular calcium, both contributing to pump stimulation.
  • The 5-HT-stimulated Na+/K+ pump activation was partly inhibited by intracellular calcium chelation.

Conclusions:

  • Serotonin (5-HT) stimulates the electrogenic Na+/K+ pump in vascular smooth muscle cells.
  • This stimulation involves activation of both 5-HT1 and 5-HT2 receptors, Na+ influx via Na+/H+ exchange, and a rise in intracellular calcium.
  • The stimulation of the Na+/K+ pump by 5-HT may act as a counter-regulatory mechanism to its contractile effects.

More Related Videos

Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography11:02

Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography

Published on: September 14, 2012

Isolation of Intrapulmonary Artery and Smooth Muscle Cells to Investigate Vascular Responses07:56

Isolation of Intrapulmonary Artery and Smooth Muscle Cells to Investigate Vascular Responses

Published on: June 8, 2022

Related Concept Videos

G-protein Coupled Receptors01:21

G-protein Coupled Receptors

G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
G Protein-coupled Receptors01:15

G Protein-coupled Receptors

G Protein-Coupled Receptors or GPCRs are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to sensory stimuli such as light, odors, hormones, cytokines, or neurotransmitters.
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
Adrenergic Receptors: β Subtype01:26

Adrenergic Receptors: β Subtype

β-adrenoceptors have varied sensitivities towards adrenaline, noradrenaline, and isoprenaline. The order of agonist potency is as follows:
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
Drugs Affecting Neurotransmitter Release or Uptake01:21

Drugs Affecting Neurotransmitter Release or Uptake

Certain drugs can affect how neurotransmitters called catecholamines, are released or taken back up in the adrenergic neuron. They can have different effects on the body's sympathetic transmission. Reserpine, a natural compound found in the Rauwolfia shrub, blocks a transporter called vesicular monoamine transporter (VMAT), which leads to a buildup of catecholamines in the cell and reduces sympathetic transmission. Another drug called guanethidine works in multiple ways, including blocking...
Smooth Muscle Contraction01:25

Smooth Muscle Contraction

Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
Drugs Affecting GI Tract Motility: Serotonin Receptor Agonists01:23

Drugs Affecting GI Tract Motility: Serotonin Receptor Agonists

Serotonin, a crucial neurotransmitter synthesized by enterochromaffin cells, plays a cardinal role in regulating gastrointestinal (GI) motility. With over 90% of the body's total serotonin in the GI tract, its influence on digestive processes is profound. Serotonin is swiftly released upon various stimuli, such as food boluses or certain drugs, triggering intrinsic sensory neurons in the myenteric plexus and extrinsic vagal and spinal sensory neurons. This leads to the activation of the...