Premium
Inhibitory effect of 5‐hydroxytryptamine on penile erectile function in the rat
Author(s) -
Finberg J.P.M.,
Vardi Y.
Publication year - 1990
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1990.tb14143.x
Subject(s) - methysergide , ketanserin , prazosin , endocrinology , medicine , stimulation , metergoline , chemistry , agonist , rauwolscine , 5 ht receptor , cyproheptadine , serotonin , antagonist , receptor
1 An increase in corporal pressure was elicited in pithed rats by stimulation of the sacral part of the spinal cord. This response was inhibited by intravenous injection of 5‐hydroxytryptamine (5‐HT) (ED 50 = 28.5 ± 2.2 μg kg −1 ). 2 The inhibitory effect of 5‐HT was blocked by methysergide and methiothepin (each 1 mg kg −1 ), but not by ketanserin (0.02 mg kg −1 ), MDL 72222 (1 mg kg −1 ) or prazosin (0.1 mg kg −1 ). 3 An inhibitory effect on the corporal pressure response to spinal stimulation was also produced by 5‐carboxyamidotryptamine (ED 50 = 5.6 ± 2.8 μg kg −1 ), but not by m‐chlorophenylpiperazine (mCPP), RU 24969, 8‐hydroxy‐2‐[di‐n‐propyl‐amino]‐tetralin (8‐OH‐DPAT) or fenfluramine (doses up to 1–2 mg kg −1 ). 4 Neither methiothepin (1 mg kg −1 ) nor clomipramine (1 mg kg −1 ) had any effect on the frequency‐response curve for increase in corporal pressure by spinal stimulation. 5 The results indicate that 5‐HT exerts an inhibitory action on penile erection by a peripheral mechanism. This effect may be mediated by vasoconstriction in cavernosal vessels, or inhibition of release of a vasodilator neurotransmitter. From the spectrum of agonist and antagonist responses, the receptor involved may be of the 5‐HT 1D subtype.