ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: Noradrenaline release from sympathetic nerve terminals was evoked by electrical nerve stimulation of an isolated segment of rat tail artery. This release was recorded by a carbon fiber electrode combined with differential pulse amperometry. The active part of the electrode (one carbon fiber 8 μm in diameter and 50 μm in length) was placed in close contact with the arterial surface. The oxidation current appearing at +120 mV and corresponding to the local noradrenaline concentration at the electrode surface was recorded every 0.5 s. No oxidation current was detected under resting conditions, but electrical stimulation evoked an immediate increase in this current. This response was suppressed when tetrodotoxin was added to the perfusion medium and was enhanced when noradrenaline reuptake was inhibited by cocaine. The amplitude of the response was increased with increasing stimulation frequencies (2–25 Hz) and train lengths (1–16 pulses). Finally, the time resolution of the method (0.5 s) was good enough to show that noradrenaline release precedes the postsynaptic response, i.e., the electrically evoked contraction of the artery.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1993.tb03284.x
