Chonnam Med J.  2005 Apr;41(1):14-18.

Effects of Norepinephrine on the Resting Activity of Medial Vestibular Nuclear Neurons in the Rat

• Jeong HS
• Huh HR
• Huang M
• Park JS

Abstract

The purpose of this study is to clarify the increasing effects of norepinephrine on the spontaneous activity of medial vestibular nuclear neurons of the rat. Sprague-Dawley rats aged 14 to 16 days were used. After decapitation and enzymatic digestion of brainstem, the portion of medial vestibular nucleus neuron was obtained by micropunching. The dissociated neurons were transferred into a recording chamber mounted on an inverted microscope and spontaneous action potentials were recorded by standard patch-clamp techniques. The spontaneous action potentials responded with increase to norepinephrine in 18 cells among 27 tested (66.7%). The spike frequency as well as the amplitude of afterhyperpolarization was increased by norepinephrine. The neurons were depolarized but its spike width was not affected by norepinephrine. These results suggest that norepinephrine increases spontaneous firing of the medial vestibular nuclear neurons by altering the afterhyperpolarization and depolarizing the neuron.

Keyword

Norepinephrine; Medial vestibular nucleus; Action potential

MeSH Terms

Action Potentials
Animals
Brain Stem
Decapitation
Digestion
Fires
Neurons*
Norepinephrine*
Patch-Clamp Techniques
Rats*
Rats, Sprague-Dawley
Vestibular Nuclei
Norepinephrine