Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Target Concepts:
Gene/Protein
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Query: UNIPROT:P08908 (
5-HT1A
)
5,574
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Norepinephrine (NE) has been shown to have a biphasic effect on evoked potentials in the CA1 region of the hippocampus of the rat in vitro, with a beta receptor mediating an increase and an alpha receptor eliciting a decrease in the amplitude of the population spike. The purpose of this study was to use selective alpha-adrenergic agonists and antagonists to determine the subtype of receptor mediating the depressant response of NE. The present investigations demonstrated that the selective alpha 1 agonist, phenylephrine (2-50 microM) elicited a dose-dependent depression of the amplitude of the population spike. Clonidine, a relatively selective alpha 2-agonist, also depressed the amplitude of the population spike, but only at concentrations (10 microM) that were inconsistent with a selective action upon alpha 2-receptors. Another alpha 2-agonist, alpha-methylnorepinephrine (100-400 nM) did not depress the amplitude of the population spike. The depressant effect of NE was antagonized by the nonselective alpha antagonist, phentolamine (0.5-50 microM) and the alpha 1-selective antagonist, prazosin (1 microM), but not by the alpha 2-selective antagonist, idazoxan (1-10 microM).
Phentolamine
and prazosin antagonized the response to phenylephrine but not to clonidine. The depressant effect of NE was not antagonized by the antagonist of serotonin and dopamine, spiperone (100 nM); conversely, the effect of 8-hydroxy-2-(di-n-propylamine) tetralin (50 microM), a
5-HT1A
receptor-selective agonist, which also depresses the amplitude of the population spike, was not antagonized by phentolamine (5 microM).(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Noradrenergic depression of synaptic responses in hippocampus of rat: evidence for mediation by alpha 1-receptors. 284 79
The antiemetic effects of flesinoxan were evaluated following s.c. administration in cats. Flesinoxan produced a dose-dependent suppression of motion sickness and also reduced xylazine-induced emesis at higher doses. Flesinoxan had a short latency to onset and may have a brief duration of action. It was slightly more potent that 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), in contrast to their relative potencies on most other in vivo measures. High doses of both agonists produced defensive behavior as a result of
5-HT1A
receptor stimulation. (-)-Propranolol, which previously reduced 8-OH-DPAT suppression of feline motion sickness, failed to reduce the antiemetic effect of flesinoxan. The dose of 3 mg/kg of NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl]piperazine) produced a slight decrease in motion sickness and added to the suppression of motion sickness by low doses of flesinoxan via an uncertain mechanism. It also reduced the antiemetic effect of higher doses of flesinoxan. In contrast, NAN-190 produced additive antiemetic effects when combined with 8-OH-DPAT and little if any reduction. NAN-190 reduced the defensiveness produced by both flesinoxan and 8-OH-DPAT.
Phentolamine
and sulpiride reduced neither the antiemetic effect nor the defensive behavior produced by flesinoxan, thus ruling out a role for alpha-adrenoceptors and dopamine D2 receptors. Flesinoxan exerted a broad spectrum antiemetic effect by an action at
5-HT1A
receptors as does 8-OH-DPAT, but differed in its response to putative
5-HT1A
receptor antagonists.
...
PMID:Antiemetic effects of flesinoxan in cats: comparisons with 8-hydroxy-2-(di-n-propylamino)tetralin. 801 49