Pharmacological evidence that somatostatin activates the m-current in hippocampal pyramidal neurons

Neurosci Lett. 1988 Aug 31;91(2):172-6. doi: 10.1016/0304-3940(88)90763-x.


In the in vitro hippocampal slice somatostatin has been shown to cause a direct hyperpolarization of CA 1 pyramidal neurons by increasing a potassium conductance which is resistant to blockade by tetraethylammonium 4-aminopyridine, or cesium ions. Results reported here demonstrate that this somatostatin-induced hyperpolarization is blocked by 1 mM barium and 5 x 10(-5) M carbachol, with the action of carbachol being reversed by atropine. Barium and carbachol both inactivate the m-current and these results suggest that somatostatin may exert its hyperpolarizing action on CA1 pyramidal cells by activation of the m-current.

MeSH terms

  • Animals
  • Atropine / pharmacology
  • Barium / pharmacology
  • Carbachol / pharmacology
  • Hippocampus / drug effects
  • Hippocampus / physiology*
  • In Vitro Techniques
  • Membrane Potentials / drug effects
  • Rats
  • Somatostatin / pharmacology*


  • Barium
  • Somatostatin
  • Atropine
  • Carbachol