Osmotic stimulation of the supraoptic nucleus: central and peripheral vasopressin release and blood pressure

M Ludwig, T Horn, M F Callahan, A Grosche, M Morris, R Landgraf

Research output: Contribution to journalArticlepeer-review

Abstract

Experiments were performed to determine the effect of direct osmotic stimulation of the supraoptic nucleus (SON) on central and peripheral vasopressin (AVP) release and arterial pressure. A microdialysis method was used to deliver hyperosmotic NaCl, mannitol or urea bilaterally into the SON and to sample SON extracellular fluid and blood. Simultaneous brain and blood microdialysis showed that hyperosmotic NaCl increased central and peripheral AVP release and increased mean arterial pressure (MAP). The pressor response was not blocked by intravenous injection of a V1-receptor antagonist, D(CH2)5Tyr(Me)AVP, suggesting that circulating AVP was not involved in that response. Hyperosmotic mannitol or urea caused an increase in central peptide release, but failed to affect MAP or peripheral AVP release. The results suggest that central AVP release within the SON may be due to osmoreceptor stimulation while the peripheral effects on AVP release and MAP are specific for sodium. The results also demonstrate the utility of brain and blood microdialysis for the delivery of stimuli into specific brain regions with simultaneous monitoring of central and peripheral peptide release.

Original languageEnglish
Pages (from-to)E351-6
JournalAmerican Journal of Physiology
Volume266
Issue number3 Pt 1
Publication statusPublished - Mar 1994

Keywords

  • Animals
  • Arginine Vasopressin
  • Blood Pressure
  • Brain
  • Male
  • Mannitol
  • Microdialysis
  • Osmosis
  • Rats
  • Rats, Wistar
  • Saline Solution, Hypertonic
  • Solutions
  • Supraoptic Nucleus
  • Urea

Fingerprint Dive into the research topics of 'Osmotic stimulation of the supraoptic nucleus: central and peripheral vasopressin release and blood pressure'. Together they form a unique fingerprint.

Cite this