Inhibition of noradrenaline release from the sympathetic nerves of the human saphenous vein by presynaptic histamine H3 receptors |
| |
Authors: | G J Molderings G Weißenborn E Schlicker J Likungu M Göthert |
| |
Institution: | (1) Institut für Pharmakologie und Toxikologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Reuterstrasse 2b, W-5300 Bonn 1, Federal Republic of Germany;(2) Klinik für Herz- und Gefäßchirurgie, Rheinische Friedrich-Wilhelms-Universität Bonn, Reuterstrasse 2b, W-5300 Bonn 1, Federal Republic of Germany |
| |
Abstract: | Summary The human saphenous vein was used to examine whether presynaptic histamine receptors can modulate noradrenaline release and, if so, to determine their pharmacological characteristics. Strips of this blood vessel were incubated with 3H]noradrenaline and subsequently superfused with physiological salt solution containing desipramine and corticosterone. Electrically (2 Hz) evoked 3H overflow was inhibited by histamine and the H3 receptor agonist R-(–)--methylhistamine. Histamine-induced inhibition of electrically evoked tritium overflow was not affected by 2-adrenoceptor blockade by rauwolscine. S-(+)--methylhistamine (up to 10 mol/l) as well as the histamine H1 and H2 receptor agonists 2-(2-thiazolyl)ethylamine (up to 3 mol/l) and dimaprit (up to 30 mol/l), respectively, were ineffective. The selective histamine H3 receptor antagonist thioperamide abolished the inhibitory effect of histamine. The histamine H2 and H1 receptor antagonists ranitidine and pheniramine, respectively, did not affect the histamine-induced inhibition of evoked tritium overflow. The present results are compatible with the suggestion that the sympathetic nerves of the human saphenous vein are endowed with inhibitory presynaptic histamine receptors of the H3 class.
Send offprint requests to M. Gothert at the above address |
| |
Keywords: | Noradrenaline release Histamine H3 receptor Presynaptic receptors Human saphenous vein |
本文献已被 SpringerLink 等数据库收录! |
|