Publicação: α-Adrenoceptor-mediated prejunctional effects of chloroethylclonidine in the canine saphenous vein
dc.contributor.author | Guimarães, Serafim | |
dc.contributor.author | Paiva, Maria Q. | |
dc.contributor.author | Pereira, Oduvaldo [UNESP] | |
dc.contributor.institution | Faculty of Medicine | |
dc.contributor.institution | Universidade Estadual Paulista (Unesp) | |
dc.date.accessioned | 2014-05-27T11:18:15Z | |
dc.date.available | 2014-05-27T11:18:15Z | |
dc.date.issued | 1997-09-01 | |
dc.description.abstract | The present study was undertaken to look for the effect of chloroethylclonidine (CEC) on prejunctional alpha-2 autoreceptors of the canine saphenous vein. The effect was tested on tritium overflow evoked by electrical stimulation from tissues preloaded with 0.2 μM 3H- norepinephrine. Yohimbine (3-300 nM) and CEC (1-125 μM) increased and UK- 14,304 reduced the overflow of tritium evoked by 300 pulses (1 Hz). The maximal increase of tritium overflow caused by yohimbine was much higher than that caused by CEC: 3.82 and 1.74 times, respectively. CEC (5 μM) abolished both the inhibition caused by UK-14,304 and the enhancement of tritium overflow caused by yohimbine. However, when CEC was added after yohimbine, it reduced the electrically evoked overflow of tritium, the maximal effect being a reduction of tritium overflow by 35%. Prazosin (1-100 nM) did not change either the inhibitory effect of UK-14,304 or the facilitatory effect of CEC. These results suggest that CEC acts on two different subtypes of prejunctional alpha-2 autoreceptors; on one of them it acts as an antagonist and increases the electrically evoked overflow of tritium (and inhibits both the effect of UK-14,304 and yohimbine); on the other it acts as an agonist and reduces the electrically evoked overflow of tritium. Alternatively, one can admit that CEC is able to inhibit alpha-2 autoreceptors, which causes an increase of the transmitter release, and to activate a nonadrenergic inhibitory receptor thus causing a reduction of the transmitter release. | en |
dc.description.affiliation | Inst. of Pharmacol. and Therapeutics Faculty of Medicine, 4200-Porto | |
dc.description.affiliation | Departamento de Farmacologia I.B. Botucatu-UNESP, 18600 Botucatu, SP | |
dc.description.affiliationUnesp | Departamento de Farmacologia I.B. Botucatu-UNESP, 18600 Botucatu, SP | |
dc.format.extent | 1326-1330 | |
dc.identifier | http://jpet.aspetjournals.org/content/282/3/1326.full.pdf | |
dc.identifier.citation | Journal of Pharmacology and Experimental Therapeutics, v. 282, n. 3, p. 1326-1330, 1997. | |
dc.identifier.issn | 0022-3565 | |
dc.identifier.scopus | 2-s2.0-0030886329 | |
dc.identifier.uri | http://hdl.handle.net/11449/65177 | |
dc.language.iso | eng | |
dc.relation.ispartof | Journal of Pharmacology and Experimental Therapeutics | |
dc.relation.ispartofjcr | 3.706 | |
dc.relation.ispartofsjr | 1,586 | |
dc.rights.accessRights | Acesso restrito | |
dc.source | Scopus | |
dc.subject | alpha adrenergic receptor | |
dc.subject | brimonidine | |
dc.subject | chloroethylclonidine | |
dc.subject | tritium | |
dc.subject | yohimbine | |
dc.subject | animal tissue | |
dc.subject | controlled study | |
dc.subject | dog | |
dc.subject | drug effect | |
dc.subject | drug mechanism | |
dc.subject | electrostimulation therapy | |
dc.subject | evoked response | |
dc.subject | female | |
dc.subject | male | |
dc.subject | neurotransmission | |
dc.subject | nonhuman | |
dc.subject | presynaptic nerve | |
dc.subject | priority journal | |
dc.subject | saphenous vein | |
dc.subject | Adrenergic alpha-Antagonists | |
dc.subject | Animals | |
dc.subject | Autoreceptors | |
dc.subject | Clonidine | |
dc.subject | Dogs | |
dc.subject | Dose-Response Relationship, Drug | |
dc.subject | Female | |
dc.subject | Male | |
dc.subject | Prazosin | |
dc.subject | Quinoxalines | |
dc.subject | Receptors, Adrenergic, alpha-2 | |
dc.subject | Saphenous Vein | |
dc.subject | Yohimbine | |
dc.title | α-Adrenoceptor-mediated prejunctional effects of chloroethylclonidine in the canine saphenous vein | en |
dc.type | Artigo | |
dspace.entity.type | Publication | |
unesp.campus | Universidade Estadual Paulista (UNESP), Instituto de Biociências, Botucatu | pt |
unesp.department | Farmacologia - IBB | pt |