Stereoselectivity of butylidenephthalide on non-adrenergic prejunctional voltage-dependent Ca(2+) channels in prostatic portion of rat vas deferens.
Eur J Pharmacol
; 786: 47-52, 2016 Sep 05.
Article
em En
| MEDLINE
| ID: mdl-27238973
ABSTRACT
The naturally occurring and synthetic butylinenephthalide (Bdph) has two geometric isomers. Z- and E-Bdph were reported to have geometric stereoselectivity for voltage-dependent calcium channels (VDCCs) in guinea-pig ileum. The aim of this study was to investigate whether the binding of Z- and E-Bdph on prejunctional VDCCs of rat vas deferens (RVD) is stereoselective. The twitch responses to electrical field stimulation (EFS, supramaximal voltage, 1 ms, 0.2Hz) were recorded on a polygraph. Z- and E-Bdph concentration-dependently inhibited the twitch responses to EFS in full tissue, prostatic portion and epididymal portion of RVD. The pIC50 value of Z-Bdph was greater than that of E-Bdph in the electrically stimulated prostatic portion of RVD, suggesting that the binding of Bdph on the non-adrenergic prejunctional VDCCs of cell membrane is stereoselective. In the prostatic portion, exogenous Ca(2+) only partially reversed the twitch inhibition by Z-Bdph, but effectively reversed those by Ca(2+) channel blockers, such as verapamil, diltiazem and aspaminol, suggesting that the action mechanisms may be different from those of Ca(2+) channel blockers. K(+) channel blockers, such as tetraethylammonium (TEA) and 4-aminopyridine (4-AP), may prolong duration of action potential to allow greater Ca(2+) entry and induced more release of transmitters. Therefore both blockers via their prejunctional actions reversed the twitch inhibition induced by Z-Bdph in all preparations of RVD by a non-specific antagonism.
Palavras-chave
4-Aminopyridine (PubChem CID: 1727); Aspaminol hydrochloride (PubChem CID: 11971482); Butylinenephthalide (Bdph); Butylinenephthalide (PubChem CID: 642376); Diltiazem hydrochloride (PubChem CID: 62920); Noradrenaline bitartrate (PubChem CID: 297812); Potassium channel blockers; Rat vas deferens; StereoSelectivity; TwiTch response; Verapamil hydrochloride (PubChem CID: 62969); Voltage-dependent calcium channels
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Anidridos Ftálicos
/
Próstata
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Ducto Deferente
/
Canais de Cálcio
Limite:
Animals
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article