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

The present study examined the antinociceptive effects of agmatine in chemical behavioural models of pain. Agmatine (1-30 mg/kg), given by i.p. route, 30 min earlier, produced dose-dependent inhibition of acetic acid-induced visceral pain, with mean ID50 value of 5.6 mg/kg. Given orally, 60 min earlier, agmatine (10-300 mg/kg) also produced dose-related inhibition of the visceral pain caused by acetic acid, with mean ID50 value of 147.3 mg/kg. Agmatine (3-100 mg/kg, i.p.) also caused significant and dose-dependent inhibition of capsaicin- and glutamate-induced pain, with mean ID50 values of 43.7 and 19.5 mg/kg, respectively. Moreover, agmatine (1-100 mg/kg, i.p.) caused marked inhibition of both phases of formalin-induced pain, with mean ID50 values for the neurogenic and the inflammatory phases of 13.7 and 5.6 mg/kg, respectively. The antinociception caused by agmatine in the acetic acid test was significantly attenuated by i.p. treatment of mice with L-arginine (precursor of nitric oxide, 600 mg/kg), naloxone (opioid receptor antagonist, 1 mg/kg), p-chlorophenylalanine methyl ester (PCPA, an inhibitor of serotonin synthesis, 100 mg/kg once a day for 4 consecutive days), ketanserin (a 5-HT2A receptor antagonist, 0.3 mg/kg), ondansetron (a 5-HT3 receptor antagonist, 0.5 mg/kg), yohimbine (an alpha2-adrenoceptor antagonist, 0.15 mg/kg) or by efaroxan (an I1 imidazoline/alpha2-adrenoceptor antagonist, 1 mg/kg). In contrast, agmatine antinociception was not affected by i.p. treatment of animals with pindolol (a 5-HT1A/1B receptor antagonist, 1 mg/kg) or idazoxan (an I2 imidazoline/alpha2-adrenoceptor antagonist, 3 mg/kg). Likewise, the antinociception caused by agmatine was not affected by neonatal pre-treatment with capsaicin. Together, these results indicate that agmatine produces dose-related antinociception in several models of chemical pain through mechanisms that involve an interaction with opioid, serotonergic (i.e., through 5-HT2A and 5-HT3 receptors) and nitrergic systems, as well as via an interaction with alpha2-adrenoceptors and imidazoline I1 receptors.
...
PMID:Mechanisms involved in the antinociception caused by agmatine in mice. 1585 29

Local administration of serotonin (5-HT) receptor agonists inhibits panic-like reactions induced by electrical stimulation of the rat dorsolateral periaqueductal grey (dlPAG). This anti-aversive effect is enhanced by chronic treatment with anti-panic drugs such as clomipramine. Since nitric oxide (NO) may mediate panic-like behavior in the dlPAG, we tested the hypothesis that chronic clomipramine treatment would also potentiate the effects of locally injected 5-HT-receptor agonists on panic-like reactions induced by intra-dlPAG injection of an NO-donor (SIN). After 21 days of daily i.p. injections of saline or clomipramine (10 mg/kg) male Wistar rats received local injections of saline, the 5-HT(1A)-receptor agonist 8-OH-DPAT (8 nmol) or the 5-HT2A/2C-receptor agonist DOI (16 nmol) followed by saline or SIN (150 nmol). NO-induced panic-like reactions were inhibited by DOI, but not by 8-OH-DPAT. Chronic clomipramine did not modify these effects but tended to produce anti-aversive effect by itself. In chronically clomipramine treated animals 8-OH-DPAT potentiated NO-induced panic-like reactions. The results indicate that the panic-like effects of NO in the dlPAG may be attenuated by 5-HT2A/2C-, but not by 5-HT1A-receptors. The anti-aversive effect of DOI is not modified by chronic clomipramine treatment.
...
PMID:Role of serotonin receptors in panic-like behavior induced by nitric oxide in the rat dorsolateral periaqueductal gray: effects of chronic clomipramine treatment. 1591 75

The present review paper describes results indicating the influence of nitric oxide (NO) on motor control. Our last studies showed that systemic injections of low doses of inhibitors of NO synthase (NOS), the enzyme responsible for NO formation, induce anxiolytic effects in the elevated plus maze whereas higher doses decrease maze exploration. Also, NOS inhibitors decrease locomotion and rearing in an open field arena. These results may involve motor effects of this compounds, since inhibitors of NOS, NG-nitro-L-arginine (L-NOARG), N(G)-nitro-L-arginine methylester (L-NAME), N(G)-monomethyl-L-arginine (L-NMMA), and 7-Nitroindazole (7-NIO), induced catalepsy in mice. This effect was also found in rats after systemic, intracebroventricular or intrastriatal administration. Acute administration of L-NOARG has an additive cataleptic effect with haloperidol, a dopamine D2 antagonist. The catalepsy is also potentiated by WAY 100135 (5-HT1a receptor antagonist), ketanserin (5HT2a and alfal adrenergic receptor antagonist), and ritanserin (5-HT2a and 5HT2c receptor antagonist). Atropine sulfate and biperiden, antimuscarinic drugs, block L-NOARG-induced catalepsy in mice. L-NOARG subchronic administration in mice induces rapid tolerance (3 days) to its cataleptic effects. It also produces cross-tolerance to haloperidol-induced catalepsy. After subchronic L-NOARG treatment there is an increase in the density NADPH-d positive neurons in the dorsal part of nucleus caudate-putamen, nucleus accumbens, and tegmental pedunculupontinus nucleus. In contrast, this treatment decreases NADPH-d neuronal number in the substantia nigra compacta. Considering these results we suggest that (i) NO may modulate motor behavior, probably by interfering with dopaminergic, serotonergic, and cholinergic neurotransmission in the striatum; (ii) Subchronic NO synthesis inhibition induces plastic changes in NO-producing neurons in brain areas related to motor control and causes cross-tolerance to the cataleptic effect of haloperidol, raising the possibility that such treatments could decrease motor side effects associated with antipsychotic medications. Finally, recent studies using experimental Parkinson's disease models suggest an interaction between NO system and neurodegenerative processes in the nigrostriatal pathway. It provides evidence of a protective role of NO. Together, our results indicate that NO may be a key participant on physiological and pathophysiological processes in the nigrostriatal system.
...
PMID:Role of nitric oxide on motor behavior. 1604 47

Nitric oxide synthase (NOS) positive neurons are located in most brain areas related to defensive reactions, including the dorsolateral periaqueductal grey (dlPAG). NOS inhibitors injected into this structure induce anxiolytic-like responses whereas NO donors promote flight reactions. Intra-dlPAG administration of carboxy-PTIO, a NO scavenger, or ODQ, a soluble guanylate cyclase inhibitor, produced anxiolytic-like effects on rats exposed to the elevated plus-maze (EPM). A double-staining experiment using NADPHd histochemistry and c-Fos immunohistochemistry in rats exposed to a cat or to the EPM showed increased activation of NO producing neurons in the dlPAG, paraventricular and lateral nuclei of hypothalamus and dorsal raphe nucleus. Cat exposure also increased activation of NOS neurons in the medial amygdala, dorsal pre-mammillary nucleus and bed nucleus of stria terminalis. Local infusion into the dlPAG of a glutamate NMDA-receptor antagonist (AP7) or a benzodiazepine agonist (midazolam) completely prevented the flight reactions induced by intra-dlPAG administration of SIN-1, a NO donor. The responses were also inhibited by the 5-HT2A/C agonist DOI but not by a 5-HT1A agonist. These results suggest a modulatory role for NO on brain areas related to defensive reactions, probably by interacting with glutamate, serotonin and/or GABA-mediated neurotransmission.
...
PMID:Role of nitric oxide in brain regions related to defensive reactions. 1609 96

Several findings relate the hippocampal formation to the behavioural consequences of stress. It contains a high concentration of corticoid receptors and undergoes plastic modifications, including decreased neurogenesis and cellular remodelling, following stress exposure. Various major neurotransmitter systems in the hippocampus are involved in these effects. Serotonin (5-HT) seems to exert a protective role in the hippocampus and attenuates the behavioural consequences of stress by activating 5-HT1A receptors in this structure. These effects may mediate the therapeutic actions of several antidepressants. The role of noradrenaline is less clear and possibly depends on the specific hippocampal region (dorsal vs. ventral). The deleterious modifications induced in the hippocampus by stress might involve a decrease in neurotrophic factors such as brain derived neurotrophic factor (BDNF) following glutamate N-methyl-D-aspartate (NMDA) receptor activation. In addition to glutamate, nitric oxide (NO) could also be related to these effects. Systemic and intra-hippocampal administration of nitric oxide synthase (NOS) inhibitors attenuates stress-induced behavioural consequences. The challenge for the future will be to integrate results related to these different neurotransmitter systems in a unifying theory about the role of the hippocampus in mood regulation, depressive disorder and antidepressant effects.
...
PMID:Modulation of stress consequences by hippocampal monoaminergic, glutamatergic and nitrergic neurotransmitter systems. 1761 38

The present report examined the effects of midbrain raphe nuclei injections of nitric oxide synthase inhibitors NG-nitro-L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI) on eating behavior. L-NAME (5-500 pmol) and 7-NI (2-200 pmol) were administered into either the dorsal or median raphe nucleus. Both nitric oxide synthase inhibitors decreased food intake in adult male Sprague-Dawley rats when injected into either raphe site. Further, eating elicited by dorsal and median raphe injections of the 5-HT1A agonist 8-OH-DPAT (0.8 nmol) was attenuated by L-NAME or 7-NI pretreatment. Our findings indicate that nitric oxide acts within the raphe to alter food intake. The inhibitory effects of L-NAME and 7-NI on eating elicited by 8-OH-DPAT further suggest that nitric oxide and 5-HT systems interact in the control of food intake.
...
PMID:Anorexigenic action of nitric oxide synthase inhibition in the raphe nuclei. 2181 25

Serotonin (5-HT) has long been considered as a key transmitter in the neurocircuitry controlling aggression. Impaired regulation of each subtype of 5-HT receptor, 5-HT transporter, synthetic and metabolic enzymes has been linked particularly to impulsive aggression. The current summary focuses mostly on recent findings from pharmacological and genetic studies. The pharmacological treatments and genetic manipulations or polymorphisms of aspecific target (e.g., 5-HT1A receptor) can often result in inconsistent results on aggression, due to "phasic" effects of pharmacological agents versus "trait"-like effects of genetic manipulations. Also, the local administration of a drug using the intracranial microinjection technique has shown that activation of specific subtypes of 5-HT receptors (5-HT1A and 5-HT1B) in mesocorticolimbic areas can reduce species-typical and other aggressive behaviors, but the same receptors in the medial prefrontal cortex or septal area promote escalated forms of aggression. Thus, there are receptor populations in specific brain regions that preferentially modulate specific types of aggression. Genetic studies have shown important gene-environment interactions; it is likely that the polymorphisms in the genes of 5-HT transporters or rate-limiting synthetic and metabolic enzymes of 5-HT (e.g., MAOA) determine the vulnerability to adverse environmental factors that escalate aggression. We also discuss the interaction between the 5-HT system and other systems. Modulation of 5-HT neurons in the dorsalraphe nucleus by GABA, glutamate and CRF profoundly regulate aggressive behaviors. Also, interactions of the 5-HT system with other neuropeptides(arginine vasopressin, oxytocin, neuropeptide Y, opioid) have emerged as important neurobiological determinants of aggression. Studies of aggression in genetically modified mice identified several molecules that affect the 5-HT system directly (e.g., Tph2, 5-HT1B, 5-HT transporter, Pet1, MAOA) or indirectly[e.g., BDNF, neuronal nitric oxide (nNOS), aCaMKII, Neuropeptide Y].The future agenda delineates specific receptor subpopulations for GABA, glutamate and neuropeptides as they modulate the canonical aminergic neurotransmitters in brainstem, limbic and cortical regions with the ultimate outcome of attenuating or escalating aggressive behavior.
...
PMID:Behavioral and pharmacogenetics of aggressive behavior. 2229 76

Hesperidin (4'-methoxy-7-O-rutinosyl-3',5-dihydroxyflavanone), a naturally occurring flavanone glycoside, was previously shown to produce an antidepressant-like effect with modultation of the serotonergic 5-HT1A and kappa-opioid receptors. In this study, the signaling mechanisms underlying their antidepressant-like effects were further evaluated by investigating in acute and chronic treatments. Results showed that chronic treatment of hesperidin or hesperitin (0.1, 0.3 and 1mg/kg, intraperitoneal, i.p.) have an antidepressant-like effect in the mouse tail suspension test (TST) without modified the locomotor activity in the open field test. Pretreatment with l-arginine (a nitric oxide (NO) precursor), sildenafil (a phosphodiesterase 5 inhibitor) or S-nitroso-N-acetyl-penicillamine (a NO donor) significantly reversed the reduction in immobility time elicited by acute treatment with hesperidin (0.3mg/kg) in the TST. Hesperidin (0.01mg/kg, a sub-effective dose in acute treatment) produced an additive antidepressant-like effect with N(G)-nitro-l-arginine (an inhibitor of nitric oxide synthase (NOS)) or 7-nitroindazole (a neuronal NOS inhibitor) in the TST. Pretreatment of animals with methylene blue (an inhibitor of NOS/soluble guanylate cyclase (sGC)) or ODQ (a specific inhibitor sGS) caused an additive effect with hesperidin in the TST. Hesperidin in the acute (1mg/kg) and chronic (0.1, 0.3 and 1mg/kg) treatments caused a significant decrease in nitrate/nitrite (NOX) levels in the hippocampus of mice. Chronic treatment with hesperidin (0.3 and 1mg/kg) also resulted in an increase in hippocampal brain-derived neurotrophic factor (BDNF) levels. These results demonstrated that the antidepressant-like effect of hesperidin is likely mediated by inhibition of l-arginine-NO-cGMP pathway and by increased of the BDNF levels in hippocampus.
...
PMID:Hesperidin exerts antidepressant-like effects in acute and chronic treatments in mice: possible role of l-arginine-NO-cGMP pathway and BDNF levels. 2470 58

NMDA receptors have been implicated in the acute response to stress, possibly mediated the nitric oxide pathway; serotonin has also been implicated in these responses, and has recently been shown to modulate the nitric oxide pathway via 5-HT1 and 5-HT2 receptors. In this work, we compare the effects of NMDA and a 5-HT1A receptor ligands on light/dark preference in adult zebrafish, and investigate whether nitric oxide mediates the effects of such drugs. The noncompetitive NMDA receptor antagonist MK-801 decreased dark preference (scototaxis), while NMDA increased it; the effects of NMDA were completely blocked by pretreatment with the nitric oxide synthase (NOS) antagonist L-NAME. SNP, a nitric oxide donor, produced a bell-shaped dose-response profile on scototaxis. Treatment with 5-HTP increased scototaxis, an effect which was potentiated by pre-treatment with NMDA, but not MK-801, and partially blocked by L-NAME. The 5-HT1A receptor antagonist WAY 100,635 decreased scototaxis, an effect which was completely blocked by L-NAME. These results suggest that tonic NOS inhibition is an important downstream effector of 5-HT1A receptors in the regulation of dark preference behavior in zebrafish, and that NOS is also under phasic independent control by NMDA receptors.
...
PMID:Interactions between serotonin and glutamate-nitric oxide pathways in zebrafish scototaxis. 2553 32

Nitric oxide (NO) and serotonin (5-HT) interact at the molecular and systems levels to control behavioral variables, including agression, fear, and reactions to novelty. In zebrafish, the 5-HT1B receptor has been implicated in anxiety and reactions to novelty, while the 5-HT1A receptor is associated with anxiety-like behavior; this role of the 5-HT1A receptor is mediated by NO. This work investigated whether NO also participates in the mediation of novelty responses by the 5-HT1B receptor. The 5-HT1B receptor inverse agonist SB 224,289 decreased bottom-dwelling and erratic swimming in zebrafish; the effects on bottom-dwelling, but not on erratic swimming, were blocked by pre-treatment with the nitric oxide synthase inhibitor L-NAME. These effects underline a novel mechanism by which 5-HT controls zebrafish reactivity to novel environments, with implications for the study of neotic reactions, exploratory behavior, and anxiety-like states.
...
PMID:Interaction between 5-HT1B receptors and nitric oxide in zebrafish responses to novelty. 2554 56


<< Previous 1 2 3 4 Next >>