Nitric oxide modulates respiratory-related neural activity in the isolated brainstem of the bullfrog

Neurosci Lett. 1998 Jul 24;251(2):81-4. doi: 10.1016/s0304-3940(98)00485-6.


The effects of nitric oxide (NO) on respiratory-related neural activity were investigated using the isolated brainstem preparation from bullfrogs (Rana catesbeiana). Addition of the NO donor, sodium nitroprusside (SNP), or the amino acid precursor for NO synthesis, L-arginine (L-Arg), produced significant increases in respiratory-related burst frequency. Inhibition of nitric oxide synthase (NOS) with N(omega)-nitro-L-arginine (L-NA), a non-selective NOS inhibitor, 7-nitro indazole (7-NI), reversibly abolished burst activity. These results suggest that production of NO, probably via neuronal NOS (nNOS), provides a facilitatory input to the respiratory central pattern generator (CPG) in the amphibian brainstem. Endogenous production of NO may be a necessary inter- or intracellular messenger for neurotransmission and/or neuromodulation of central respiratory drive to motor effectors in the bullfrog.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain Stem / metabolism*
  • Nitric Oxide / physiology*
  • Rana catesbeiana
  • Respiratory Physiological Phenomena*


  • Nitric Oxide