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)

Anti-idiotypic antibodies were generated by immunizing rabbits with affinity-purified antibodies to serotonin (5-hydroxytryptamine; 5-HT). Anti-5-HT activity was removed from the resulting antisera by chromatography through a 5-HT affinity column. The anti-idiotypic antibodies were demonstrated by enzyme-linked immunosorbent assay to bind to affinity-purified whole anti-5-HT antibodies and their Fab fragments. Anti-idiotypic antibodies, purified by affinity chromatography on columns to which antibodies to 5-HT were coupled, competed with 5-HT (covalently bound to protein) for the binding sites on anti-5-HT antibodies and serotonin binding protein. The anti-idiotypic antibodies antagonized the binding of [3H]5-HT to membranes isolated from the cerebral cortex, striatum, and raphe area more than to membranes from hippocampus or cerebellum. The anti-idiotypic antibodies also blocked the binding of the 5-HT1B-selective ligand (-)-[125I]iodocyanopindolol (in the presence of 30 microM isoproterenol) to cortical membranes. In contrast, anti-idiotypic antibodies failed to inhibit binding of the 5-HT1A-selective ligand 8-hydroxy-2-(di-n-[3H]propylamino)-tetralin [( 3H]8-OH-DPAT) to raphe area membranes or hippocampal membranes. These observations suggested that the anti-idiotypic antibodies may recognize some 5-HT receptor subtypes but not others. This hypothesis was tested by ascertaining the ability of anti-idiotypic antibodies to immunostain cells transfected in vitro with cDNA encoding the 5-HT1C or 5-HT2 receptor or with a genomic clone encoding the 5-HT1A receptor. Punctate sites of immunofluorescence were found on the surfaces of fibroblasts that expressed 5-HT1C and 5-HT2 receptors, but not on the surfaces of HeLa cells that expressed 5-HT1A receptors. Immunostaining of cells by the anti-idiotypic antibodies was inhibited by appropriate pharmacological agents: immunostaining of cells expressing 5-HT1C receptors was blocked by mesulergine (but not ketanserin, 8-OH-DPAT, or spiperone), whereas that of cells expressing 5-HT2 receptors was blocked by ketanserin or spiperone (but not mesulergine or 8-OH-DPAT). The anti-idiotypic antibodies failed to inhibit the uptake of [3H]5-HT by serotonergic neurons. It is concluded that the anti-idiotypic antibodies generated with anti-5-HT serum recognize the 5-HT1B, 5-HT1C, and 5-HT2 receptor subtypes; however, neither 5-HT1A receptors nor 5-HT uptake sites appear to react with these antibodies.
J Neurochem 1991 Sep
PMID:Identification of serotonin receptors recognized by anti-idiotypic antibodies. 186 Nov 58

Several recent studies have shown that the 5-HT1A agonist indorenate possesses antianxiety properties. In the present study we report on other behavioural actions of this drug. Indorenate (31.6 mg/kg) induced flat body posture, forepaw treading and hind limb abduction, behavioural characteristics of the serotonin syndrome. After indorenate injection these same behaviours were observed in animals pretreated with p-chlorophenylalanine (400 mg/kg X 3 days), suggesting that the action of this compound is not mediated via serotonin release. The beta-5-HT1 blockers, (-) pindolol (2 mg/kg) or (-) alprenolol (5 mg/kg), did not prevent the actions of indorenate on the serotonin syndrome. Indorenate (10 mg/kg) stimulated the masculine sexual behaviour by reducing the number of intromissions preceding ejaculation. Higher doses (17.8 mg/kg) cause a complete inhibition of sexual behaviour. (-) Pindolol (2 mg/kg) or (-) alprenolol (5 mg/kg) did not antagonize the facilitatory actions of indorenate on male sexual behaviour. A high dose of indorenate (31.6 mg/kg) resulted in an impairment of the motor coordination as tested in a treadmill apparatus. These data reveal that indorenate possesses, in addition to its antianxiety effects, other behavioural characteristics that, however, appear at higher dose levels.
Pharmacol Biochem Behav 1990 Sep
PMID:Behavioural actions of the serotonergic anxiolytic indorenate. 197 77

In pigs, behavioural responses were examined after administration of 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT), a full agonist at 5-hydroxytryptamine (5-HT) receptors of the 5-HT1A subtype, and the pyrimidinylpiperazine derivatives ipsapirone and Bay Vq 7813 (2-[4-(2-pyrimidinyl)-1-piperazinylpropyl]-1,2-benzisothiazol++ +-3(2H) one-1,1-dioxide), which act as partial agonists at 5-HT1A receptors. The most prominent behavioural response examined after 8-OH-DPAT, 0.5 mg/kg i.m., ipsapirone, 2-5 mg/kg i.m., and Bay Vq 7813, 0.5-2 mg/kg i.m. or i.v., were head shakes. The potency of the three drugs to induce this behaviour correlated with their activity at 5-HT1A receptors as determined by inhibition of forskolin-stimulated adenylate cyclase, substantiating that the head shake response has potential as a quantitative probe of in vivo receptor function. The 5-HT2/5-HT1C receptor antagonist ritanserin did not counteract the head shakes induced by ipsapirone, suggesting that neither 5-HT2 nor 5-HT1C receptors are involved in mediation of this response to this 5-HT1A receptor agonist in pigs. Once daily administration of Bay Vq 7813 or ipsapirone for 3-5 days led to a reduction in the head shake response. 1-Pyrimidinylpiperazine (1-PP), a pharmacologically active metabolite shared by ipsapirone, Bay Vq 7813, and related pyrimidinylpiperazine derivatives, did not induce behavioural alterations in pigs. The data provide further evidence that marked species differences exist in functional responses to 5-HT receptor ligands.
Naunyn Schmiedebergs Arch Pharmacol 1990 Sep
PMID:The behavioural responses to 8-OH-DPAT, ipsapirone and the novel 5-HT1A receptor agonist Bay Vq 7813 in the pig. 214 68

Serotonin receptor ligands, with differential affinity for subtypes of serotonin (5-HT) receptors, were administered intravenously or iontophoretically to urethane-anesthetized rats and the effects of these compounds on glutamate-evoked firing of spinal motoneurons were tested. The excitability of spinal motoneurons was markedly enhanced after intravenous administration of the selective 5-HT1A ligand 8-hydroxy-2-(di-n-propylamino) tetralin (DPAT) in rats with acute spinal transections at C1. However, local application of DPAT, directly into the ventral horn by microiontophoresis, inhibited the glutamate-evoked firing of motoneurons in direct contrast to the facilitatory effects of iontophoretically applied 5-HT. The DPAT-induced inhibition may have been nonspecific, since it was not antagonized by methysergide. Other 5-HT agonists, with relatively selective affinity for 5-HT1B, 5-HT1C and 5-HT2 receptors, increased the excitability of spinal motoneurons when applied iontophoretically or intravenously. The excitatory effect of iontophoretically applied 5-HT was antagonized by the nonselective 5-HT antagonist, methysergide and by ketanserin and ritanserin, which have relatively selective affinity for 5-HT1C and 5-HT2 receptors. These results indicate that 5-HT1A receptors do not mediate facilitation of excitability of motoneurons produced by local application of 5-HT directly into the vicinity of the motoneurons. However, the marked increase in firing of motoneurons that was caused by intravenous administration of DPAT in spinal transected rats, suggests that 5-HT1A receptors in the spinal cord may participate in 5-HT-induced enhancement of somatomotor outflow, at sites presynaptic to the motoneurons. The iontophoretic results suggest that 5-HT1B, 5-HT1C and 5-HT2 receptors may all play a role in facilitation of the excitability of spinal motoneurons by locally applied 5-HT. Differentiation between these subtypes of receptor awaits the development of more completely selective agonists and antagonists.
Neuropharmacology 1990 Sep
PMID:Receptor subtypes mediating facilitation by serotonin of excitability of spinal motoneurons. 214 74

Buspirone, an azapirone derivative and a 5-HT1A partial agonist, is the first nonbenzodiazepine anxiolytic introduced into medicine for the treatment of generalized anxiety disorder. A series of well-controlled clinical trials demonstrated that its anxiolytic properties were similar to those of various benzodiazepines and significantly better than placebo. More recently, antidepressant effects were also observed. Patients with clinical indications for which buspirone seems to be particularly appropriate are those with generalized anxiety disorder, those with chronic anxiety, the anxious elderly, and, perhaps, many patients of all ages who suffer from mixed symptoms of anxiety and depression. Studies conducted with patients suffering from panic disorder have so far been inconclusive, and thus buspirone is, for the present at least, not recommended for routine treatment of panic disorder. Buspirone seems to be most helpful in anxious patients who do not demand immediate gratification or the immediate relief they associate with the benzodiazepine response. Slower and more gradual onset of anxiety relief is balanced by the increased safety and lack of dependency-producing aspects of buspirone. Finally, whether or not buspirone may possess "curative" properties, in addition to "anxiety-suppressant" properties, that allow the patient to improve coping skills with time requires further exploration.
J Clin Psychiatry 1990 Sep
PMID:Buspirone in clinical practice. 221 69

Serotonin is a monoamine and is widely distributed in the human organism. Serotonin is synthesized from the amino acid tryptophane and is broken down via mono-amino-oxydase enzymes to 5-hydroxy-indol-acetic acid and by acetylizing and methylizing to melantonin. In 1986, a consensus concerning the classification of the serotonergic receptors was established. Three main classes were determined, viz: 5-HT1, 5-HT2 and 5-HT3. 5-HT1 receptors were further subdivided into A, B, C and D-receptors and, of these, the 5-HT1A-receptor is involved in the centrally mediated blood pressure control via reduction in the pre- and postganglionic sympathetic activity. The 5-HT2 receptors are primarily involved in control of peripheral blood pressure where agonizing results in vascular contraction of the large arteries and veins and thrombocyte aggregation. The 5-HT1 receptors are also involved peripherally in connection with release of relaxing factors derived from endothelium. In vitro and in animal experiments, it has been demonstrated that serotonin is capable of inducing arrhythmia and myocardial dysfunction via 5-HT3 receptors. Several preparations with effects on both the central and peripheral serotonergic receptors are already marketed for treatment of hypertension and other conditions.
Ugeskr Laeger 1990 Sep 24
PMID:[Serotonin and cardiovascular control]. 221 14

Stimulation of astroglial 5-HT1A receptors causes astroglial cells to acquire a more mature morphology and to release a factor (or factors) which promotes growth of serotonergic neurons. By using an antibody-blocking approach, we have shown that at least one of the growth-promoting factors thus released is the astroglial-specific protein S-100. This may be a particularly important observation, in view of studies implicating S-100 in both Down's syndrome and Alzheimer's disease.
Brain Res 1990 Sep 24
PMID:Stimulation of astroglial 5-HT1A receptors releases the serotonergic growth factor, protein S-100, and alters astroglial morphology. 224 32

Increasing brain 5-hydroxytryptamine (5-HT) function in humans raises plasma concentrations of prolactin, growth hormone and ACTH. Measurement of these hormonal responses provides an index of the functional activity of brain 5-HT pathways. More recent strategies have included the use of directly-acting 5-HT receptor agonists to probe the function of specific receptor subtypes; at present these studies are limited by the questionable selectivity of the agonists employed. Using 5-HT neuroendocrine testing it can be shown that lithium specifically increases the prolactin release mediated by 5-HT pathways. Further studies are needed to determine if this effect is caused by an enhanced sensitivity of post-synaptic 5-HT1A receptors.
J Neurosci Methods 1990 Sep
PMID:5-HT neuroendocrine responses during psychotropic drug treatment: an investigation of the effects of lithium. 225 42

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.
J Neurosci Methods 1990 Sep
PMID:Application of brain microdialysis to study the pharmacology of the 5-HT1A autoreceptor. 225 48

The actions of 5-hydroxytryptamine (5-HT) on the electrically induced twitch responses of mouse vas deferens were studied. 5-HT at the concentration range of 10(-8) to 10(-4) M produced a "bell-shaped" concentration-response curve on the field-stimulated twitch contractions; the enhancement of the contractions was maximum at 10(-5) M and progressively reduced at the concentrations of more than 10(-5) M. In the presence of ketanserin, whereas the stimulatory response to low concentrations of 5-HT (less than or equal to 10(-6) M) was not changed, that to high concentrations was reversed. The stimulation by 5-HT (less than or equal to 10(-5) M) was principally antagonized by MDL 72222. In the presence of both MDL 72222 and ketanserin, 5-HT inhibited the twitch contractions in a dose-dependent manner. 8-Hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and BP-554 (1-[3-(3,4-methylenedioxyphenoxy)propyl]-4-phenyl piperazine), selective 5-HT1A agonists, only inhibited the twitch contractions. Downward slope of the contraction-response curve of 5-HT (greater than or equal to 10(-5) 5 M) was shifted to right in the presence of 8-OH-DPAT. 5-HT and 8-OH-DPAT had no effect on the tension of unstimulated organs. Contractions elicited by ATP were potentiated by 5-HT, which was antagonized by ketanserin. 8-OH-DAPT did not affect ATP-elicited contractions. These results suggest the presence of presynaptic 5-HT1, maybe 5-HT1A and 5-HT3 receptors mediating inhibition and potentiation, respectively, of neurotransmitter release and of postsynaptic responsible for enhancing neurogenic contractions in mouse vas deferens.
J Pharmacol Exp Ther 1990 Sep
PMID:5-Hydroxytryptamine modulation of electrically induced twitch responses of mouse vas deferens: involvement of multiple 5-hydroxytryptamine receptors. 239 4


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