ISSN:
1432-1912
Keywords:
Noradrenaline release
;
Serotonin receptors
;
5-HT1D receptor
;
Presynaptic receptors
;
Human saphenous vein
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary The human saphenous vein preincubated with [3H]noradrenaline was used to determine the pharmacological properties of the release-inhibiting presynaptic serotonin (5-HT) receptor on the sympathetic nerves. The overflow of tritium evoked by transmural electrical stimulation (2 Hz) was concentration-dependently inhibited by drugs known to stimulate 5-HT receptors in the following rank order: oxymetazoline ≥ 5-HT ≥ 5-carboxamidotryptamine = 5-methoxytryptamine = sumatriptan 〉 tryptamine 〉 N,N(CH3)2-5-HT = yohimbine = 8-hydroxy-2-(di-n-propylamino)-tetraline. The potencies of these agonists in inhibiting overflow were significantly correlated with their affinities for 5-HT1B and 5-HT1D binding sites, but not with those for 5-HT1A or 5-HT1C binding sites. 5-Aminotryptamine, methysergide, ipsapirone, cyanopindolol, SDZ 21009 and metergoline dit not produce a significant inhibition. Metitepine and methysergide antagonized the inhibitory effect of 5-HT, whereas spiroxatrine, propranolol, ketanserin and ICS 205-930 did not. These data exclude the idea that the inhibitory presynaptic 5-HT receptor on the sympathetic nerves belongs to the 5-HT2 and 5-HT3 receptor class; the pattern of agonist potencies suggests that the receptor is very similar to the 5-HT1D receptor subtype.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00169451
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