Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P08908 (5-HT1A)
 5,574 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

5-Hydroxytryptamine (5-HT) receptors of the 5-HT1A subtype are localized on serotoninergic cells and dendrites in the raphe nuclei of the brain stem and are believed to regulate synaptic 5-HT release through an inhibitory influence on serotoninergic impulse flow. The effects of 5-HT1A agonists on 5-HT release can, therefore, only be detected by measurement of 5-HT release from intact serotoninergic neurones. Here we review the evidence that the microdialysis technique, when applied to the anaesthetized rat, is able to detect extracellular 5-HT in the brain which derives from serotoninergic neurones and changes in accordance with serotoninergic neuronal activity. We have observed that a range of 5-HT1A agonists, including 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), inhibit 5-HT release in hippocampus, most probably by acting on somatodendritic 5-HT1A autoreceptors in the dorsal raphe nucleus. The inhibitory action of 8-OH-DPAT and several other selective 5-HT1A receptor active drugs on 5-HT release is sensitive to pindolol, further supporting the idea that the 5-HT receptor being measured is of the 5-HT1 subtype. Two drugs, BMY 7378 and NAN-190, which show 5-HT1A antagonist properties in certain models, reduce 5-HT release indicating that they have mixed agonist/antagonist actions at the 5-HT1A receptor. Our data indicate that measurement of 5-HT release in rat brain using the microdialysis technique may be a useful method to probe the pharmacology of the 5-HT1A autoreceptor in vivo.
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PMID:Application of brain microdialysis to study the pharmacology of the 5-HT1A autoreceptor. 225 48

NAN-190 has been reported to be a 5-HT1A antagonist in drug discrimination studies. In order to determine if the effect of NAN-190 was directly due to competitive inhibition at 5-HT1A receptors, 5-HT1A-mediated inhibition of adenylyl cyclase in hippocampal membranes was investigated. NAN-190 (10(-10)-10(-5) M), by itself, was found to have no effect on forskolin-stimulated adenylyl cyclase. NAN-190, however, did shift the 5-carboxamidotryptamine (a 5-HT1A agonist) log-concentration inhibition curve to the right in a concentration-dependent manner, typical of competitive antagonism. Schild analysis revealed a KB of 1.9 nM for NAN-190. Thus, NAN-190 appeared to be a potent competitive 5-HT1A antagonist using the in vitro adenylyl cyclase system. [3H]NAN-190 was synthesized and its 5-HT1A receptor binding properties were characterized and compared with the 5-HT1A agonist radioligand, [3H]8-hydroxy-2-(di-n-propylamino)tetralin ([3H]8-OH-DPAT). The 5-HT1A agonists, serotonin (5-HT) and 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) competed with equal affinities regardless of the radioligand used to label the 5-HT1A receptors. [3H]NAN-190 and [3H]8-OH-DPAT labeled the same number of sites in rat hippocampus, striatum and frontal cortex. Guanosine-5'-O-(3-thio)triphosphate (GTP gamma S) and 5-guanylyl-imidodiphosphate (GppNHp), non-hydrolyzable analogs of GTP, inhibited specific [3H]NAN-190 binding. Adenosine-5'-O-(3-thio)triphosphate (ATP gamma S) and 5-adenylyl-imidodiphosphate (AppNHp) were ineffective. This guanylyl nucleotide-specific effect is generally associated with agonist radioligand binding to a GTP-binding protein coupled receptor. However, [3H]8-OH-DPAT was far more sensitive than [3H]NAN-190 to the Bmax reducing effects of GTP and GTp gamma S. We propose that the test for a reduction in Bmax by non-hydrolyzable guanylyl nucleotides may be more sensitive than other tests for quantifying agonist activity and may demonstrate that NAN-190 has low intrinsic activity. In summary, NAN-190 displayed antagonist-like properties in functional models of 5-HT1A receptor activity and possibly partial agonist-like properties in radioligand binding experiments.
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PMID:NAN-190: agonist and antagonist interactions with brain 5-HT1A receptors. 228 13

1-(2-Methoxyphenyl)-4-[4-(2-phthalimido)butyl]piperazine, NAN-190, is a novel compound with putative 5-HT1A antagonist properties. In the present study, the effects of NAN-190 were examined with regard to functional pre- and post-synaptic 5-HT1A receptor-mediated events, using in vivo brain microdialysis and behavioural techniques. Our findings provide evidence that NAN-190 acts as a mixed agonist/antagonist at central 5-HT1A receptors. Thus, NAN-190 blocked (+)8-OH-DPAT-induced behaviour in reserpinized rats, indicating antagonist properties at postsynaptic 5-HT1A receptors. However, the compound was also able to decrease the release of 5-HT in vivo, tentatively due to an agonist action at somatodendritic 5-HT1A autoreceptors. These data extend previous information on the pharmacological profile of NAN-190 and further emphasizes the difference between pre- and postsynaptic 5-HT1A receptors in brain.
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PMID:Mixed agonist/antagonist properties of NAN-190 at 5-HT1A receptors: behavioural and in vivo brain microdialysis studies. 232 21

The actions of NAN-190, a putative 5-HT1A antagonist, were assessed in rats. The selective 5-HT1A agent ipsapirone suppressed operant responding, but this effect was not antagonised by NAN-190, which suppressed responding itself in a dose-related manner, and had additive effects when administered with ipsapirone. These data do not support suggestions that NAN-190 is a 5-HT1A antagonist. NAN-190 may be a 5-HT1A partial agonist which can antagonise effects of full 5-HT1A agonists.
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PMID:In vivo interactions of NAN-190, a putative selective 5-HT1A antagonist, with ipsapirone. 262 48

We studied the effects of serotonin (5-HT) on intrinsic and synaptic responses of hippocampal CA1 cells. The effects were partially mimicked by the 5-HT1A receptor agonist, 8-OH-DPAT, and prevented by the 5-HT1A receptor antagonist, NAN-190. Polysynaptic fast and slow inhibitory postsynaptic potentials (IPSPs) were reduced in amplitude by 60-70% following application of both 5-HT and 8-OH-DPAT. Monosynaptic fast IPSPs were reduced by 60% and slow IPSPs by 90% following application of both drugs. Since there is a temporal overlap of fast and slow IPSPs, the reduction in fast IPSPs could have arisen indirectly from the larger effect of 5-HT on slow IPSPs. To overcome this problem we blocked the slow IPSPs with new, potent GABA-B antagonists, but still observed a similar reduction in the fast IPSP with 5-HT and 8-OH-DPAT. However, the reductions in the fast IPSPs could also have arisen from the 5-HT-induced total conductance increases. Using single-electrode voltage clamp and intracellular K+ channel blockers we still observed similar changes. 5-HT and 8-OH-DPAT had no effect upon GABA-A-mediated currents evoked by iontophoretic GABA application to the dendrites or the soma of CA1 pyramidal cells, Putative inhibitory internuerons were hyperpolarized by 5-HT and their evoked EPSPs strongly reduced by 5-HT and 8-OH-DPAT. Our data indicate that 5-HT modulates fast and slow synaptic inhibition of principal cells using presynaptic mechanisms involving the inhibition of inhibitory interneurons.
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PMID:Serotonin reduces inhibition via 5-HT1A receptors in area CA1 of rat hippocampal slices in vitro. 747 76

In the present study, using a two-lever drug discrimination procedure, we characterized the effects of a series of chemically-diverse, novel 5-HT1A receptor agonists and antagonists in rats trained to discriminate the serotonin (5-HT)1A receptor agonist, 8-hydroxy-2-(di-N-propylamino) tetralin (8-OH-DPAT) (0.31 mg/kg, i.p.) from saline. In analogy to the 5-HT1A receptor agonists, ipsapirone (a pyrimidinylpiperazine) and flesinoxan (a benzodioxane), the arylpiperazine derivatives, WY-48,723 and WY-50,324, as well as the methoxynaphtylpiperazines, S 14506 and S 14671, substituted 100% for the discriminative stimulus (DS) effects of 8-OH-DPAT, with the latter two displaying remarkable potency [50 effective doses (ED50s): 1.25, 0.34, 0.05, 0.69, 0.009 and 0.006 mg/kg, s.c., respectively]. In contrast, an additional pyrimidinylpiperazine, zalospirone, failed to fully mimick the training drug (maximal effect: 40%) even at a dose markedly disrupting response rates (2.5 mg/kg, s.c.). The potency of agonists in generalizing to 8-OH-DPAT correlated significantly (P < .05) with their affinity at rat hippocampal 5-HT1A receptors in vitro (r = .78), and with their potency to induce hypothermia in the rat (r = .96). S 15535 and S 15931, novel benzodioxopiperazines possessing mixed 5-HT1A autoreceptor agonist/postsynaptic 5-HT1A receptor antagonist properties, antagonized (approximately 75%) the discriminative stimulus (DS) properties of 8-OH-DPAT (ED50s: 6.9 and 0.97 mg/kg, s.c., respectively), although their structural analogue, S 14489, reduced by only 50% the action of 8-OH-DPAT. The 5-HT1A receptor antagonists, (+/-)-pindolol (-70%; ED50: 0.65 mg/kg, s.c.), (-)-alprenolol (-67%; ED50: 7.1) and NAN-190 (-80%; ED50: 1.5), all blocked the 8-OH-DPAT DS. Likewise, several novel antagonists at 5-HT1A autoreceptors and postsynaptic 5-HT1A receptors; the benzoisothiazolpiperazine, SDZ 216-525 (-83%; ED50: 0.64), the aryloxyalkylamine, (-)-tertatolol (-83%; ED50: 7.7) and the methoxyphenylpiperazine, (+)-WAY 100,135 (-80%; ED50: 17.0), antagonized the 8-OH-DPAT cue. Antagonist potency correlated significantly with affinity at 5-HT1A receptors (r = .83) and potency for antagonism of 8-OH-DPAT-induced hypothermia (r = .83). Antagonists showed only variable and not significant (P > .05) generalization rates (13-50%) when tested alone.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:A drug discrimination analysis of the actions of novel serotonin1A receptor ligands in the rat using the 5-HT1A receptor agonist, 8-hydroxy-2-(di-n-propylamino)tetralin. 747 72

The effect of fluvoxamine, a selective serotonin (5-HT) reuptake inhibitor, was studied in a model of anxiety and/or obsessive compulsive disorder (OCD) in mice. In the anxiety/OCD model, marble-burying behavior, marble-burying was significantly suppressed by fluvoxamine at 30 and 60 mg/kg, p.o. and the monoamine reuptake inhibitor clomipramine, at 60 mg/kg, p.o. No suppressive effect, however, was observed by the selective norepinephrine reuptake inhibitor desipramine at doses from 15 to 60 mg/kg, p.o. Suppressive effects were obtained by the serotonergic anxiolytic buspirone at 30 and 60 mg/kg, p.o. and the benzodiazepine anxiolytic diazepam at 10 mg/kg, p.o. The effect of fluvoxamine on marble-burying was slightly attenuated after repeated administration. On the other hand, both the effects of buspirone and diazepam completely disappeared after repeated administration. Effect of fluvoxamine on the marble-burying was unaffected by the 5-HT2 antagonist ritanserin. However, the 5-HT1A antagonist NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl] piperazine) inhibited the suppressive effect of fluvoxamine on the marble-burying. From these results, the 5-HT1A-receptor subtype may be involved in the suppressive effect of fluvoxamine on the marble-burying, but the 5-HT2-receptor subtype is not involved in this effect.
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PMID:5-HT1A-receptor subtype mediates the effect of fluvoxamine, a selective serotonin reuptake inhibitor, on marble-burying behavior in mice. 749 84

The effect of fluvoxamine, a selective serotonin (5-HT) reuptake inhibitor, was studied in the forced-swimming test, a model of depression, in mice. Fluvoxamine at 60 mg/kg, p.o. significantly decreased the immobility time in the forced-swimming test. A similar effect was observed by the selective norepinephrine reuptake inhibitor desipramine at the same dose. Furthermore, the suppression of immobility time was slightly potentiated by repeated administration of fluvoxamine, and a significant effect was observed at 30 mg/kg, p.o. The effect of fluvoxamine on forced-swimming was unaffected by the 5-HT2 antagonist ritanserin. On the other hand, the 5-HT1A antagonist NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl] piperazine) potentiated the effect of fluvoxamine on forced-swimming. It is expected, however, that a 5-HT1A antagonist should antagonize the effect of fluvoxamine when 5-HT1A mediates the suppressive effect of fluvoxamine on the immobility time in forced-swimming. From these results, neither the 5-HT1A- nor the 5-HT2-receptor subtype is involved in the suppressive effect of fluvoxamine on the immobility associated with forced-swimming.
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PMID:Neither the 5-HT1A- nor the 5-HT2-receptor subtype mediates the effect of fluvoxamine, a selective serotonin reuptake inhibitor, on forced-swimming-induced immobility in mice. 749 85

To explore the role of 5-HT receptor subtypes in controlling aversion, we measured the effect of 5-HT1A and 5-HT2A/2C receptor agonists microinjected into the dorsal periaqueductal gray (DPAG) of rats on aversive behavior induced by electrical stimulation of the same brain area. The 5-HT1A agonists 8-OH-DPAT (4-16 nmol) and BAY-R-1531 (4-16 nmol) raised the threshold of aversive electrical stimulation in a dose-dependent way. Similarly, microinjection of the 5-HT2A/2C agonist DOI (4-16 nmol) increased the aversive mCPP (16 and 32 nmol) was ineffective. Previous intra-DPAG administration of the 5-HT1A receptor blocker NAN-190 (40 nmol) antagonized the antiaversive effect of 8-OH-DPAT (8 nmol), whereas pretreatment with the 5-HT2A receptor blocker spiperone (10 nmol) antagonized the effect of DOI (16 nmol). Spiperone also counteracted the effect of 8-OH-DPAT and NAN-190 counteracted the effect of DOI. These results indicate that activation of 5-HT1A and 5-HT2A receptors inhibits aversion in the DPAG and that both receptors have to be functional for the expression of each one's activation to occur.
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PMID:Role of 5-HT receptor subtypes in the modulation of dorsal periaqueductal gray generated aversion. 750 49

The modulating effects of 5-HT1A and 5-HT2 receptor agonists on behaviour spinal excitatory amino acid (EAA) agonists were examined. Intrathecal (i.th.) administration of both N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) produce a behavioural syndrome of caudally directed biting and scratching. Serotonin (5-HT) agonists were coadministered with either NMDA or AMPA, and changes in EAA-induced behaviour were scored. All drugs were administered i.th. The 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT) (15-60 nmol) reduced both NMDA (0.25 nmol) and AMPA (0.06 nmol) induced behaviour in a dose-dependent manner, and preadministration of the 5-HT1A receptor antagonist, 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl]piperazine hydrobromide (NAN-190) (20 nmol) reversed this effect. The administration of the 5-HT2 agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) (0.7-28 nmol) produced a dose-dependent behavioural syndrome similar to the EAA agonists. This was reversed by preadministration of ritanserin (10 nmol), a 5-HT2 antagonist. When DOI was coadministered with NMDA (0.25 nmol) or MAPA (0.06 nmol) there was an increase in the behaviour recorded and this effect was antagonised by ritanserin. The results of this study implicate that in the spinal cord subtypes of 5-HT receptors have different effects on modulation of behaviour induced by activation of the NMDA or the AMPA receptors; the activated 5-HT1A receptors have an inhibitory effect whereas activation of the 5-HT2 receptors enhance the induced behaviour.
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PMID:Different functions of spinal 5-HT1A and 5-HT2 receptor subtypes in modulating behaviour induced by excitatory amino acid receptor agonists in mice. 750 33


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