Endothelial expression of the 5-hydroxytryptamine1B antimigraine drug receptor in rat and human brain microvessels

Neuroscience. 1998 Oct;86(4):1031-5. doi: 10.1016/s0306-4522(98)00196-1.


In addition to triggering vasoconstriction of peripheral blood vessels, which led to its discovery as a circulating neurohormone 50 years ago, serotonin (5-hydroxytryptamine) acts as a neurotransmitter/ modulator in the central nervous system and regulates local cerebral blood flow and vascular permeability through direct and indirect effects on intraparenchymal microvessels. Among the various 5-hydroxytryptamine receptors which mediate these effects, particular attention has been paid to the 5-hydroxytryptamine1B and 5-hydroxytryptamine1D subtypes, as the preferred targets of modern antimigraine agents. Immunoelectron microscopic labeling of the 5-hydroxytryptamine1B receptor in rat brain parenchyma has revealed a distinct localization to the endothelium of microvessels, which was predominantly cytoplasmic as opposed to membrane-bound, contrary to that on preterminal unmyelinated axons [Riad et al. (1997) Soc. Neurosci. Abstr. 23, 1214]. Similar observations have now been made in human cortical tissue, in which the expected localization of the vascular 5-hydroxytryptamine1B receptor to periarteriolar myocytes was also confirmed. Such a dual localization in human brain microvessels suggests that the 5-hydroxytryptamine1B receptor might mediate opposite effects, vasodilatory and contractile, depending upon its activation by circulating or centrally released 5-hydroxytryptamine. It raises new possibilities as regards 5-hydroxytryptamine effects on human brain microvessels in health and disease, and notably the triggering of migraine headache.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Capillaries / cytology
  • Capillaries / metabolism
  • Capillaries / pathology
  • Endothelium, Vascular / cytology
  • Endothelium, Vascular / metabolism*
  • Endothelium, Vascular / pathology
  • Humans
  • Migraine Disorders / metabolism*
  • Migraine Disorders / pathology
  • Muscle, Smooth, Vascular / cytology
  • Muscle, Smooth, Vascular / metabolism*
  • Muscle, Smooth, Vascular / pathology
  • Rats
  • Receptor, Serotonin, 5-HT1B
  • Receptors, Serotonin / biosynthesis*
  • Reverse Transcriptase Polymerase Chain Reaction


  • HTR1B protein, human
  • Receptor, Serotonin, 5-HT1B
  • Receptors, Serotonin