Publication Date:
1979-07-27
Description:
By using two separate electrodes with tips inside a single feline motoneuron, current-voltage characteristics were studied during extracellular iontophoresis of noradrenaline. The usually observed hyperpolarization was accompanied by an increase in membrane resistance and became larger with polarizing and smaller with depolarizing currents. During large depolarizing current injections, the noradrenaline-induced potential reversed its direction, usually at a membrane potential of about -20 millivolts. These data are compatible with the concept that noradrenaline hyperpolarizes nerve cells by decreasing resting membrane conductances to sodium and potassium ions. The observation could also be explained by a nonspecific decrease in ion permeability that is associated with a hyperpolarization due to sodium pump activation.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Marshall, K C -- Engberg, I -- New York, N.Y. -- Science. 1979 Jul 27;205(4404):422-4.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/451613" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Cats
;
Membrane Potentials/drug effects
;
Neurons/drug effects/*physiology
;
Norepinephrine/*pharmacology
;
Potassium/metabolism
;
Sodium/metabolism
;
Spinal Cord/drug effects/*physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
