Chronic Administration of 5-HT1A Receptor Agonist Relieves Depression and Depression-Induced Hypoalgesia

Previous studies have shown that depressed patients as well as animal models of depression exhibit decreased sensitivity to evoked pain stimuli, and serotonin is indicated to be involved in depression-induced hypoalgesia. The purpose of this study was to investigate the potential role of 5-HT1A receptor in the depression-induced hypoalgesia. Acute or chronic administration of 5-HT1A receptor agonist, 8-OH-DPAT, was performed in olfactory bulbectomy (OB) and sham-operated rats. The depression-like behavior and pain thresholds were measured using open-field test and radiant heat thermal pain test, respectively. We found that acute administration of 8-OH-DPAT increased locomotor activity and pain thresholds in the sham rats but had no effect on the OB rats. In contrast, chronic administration of 8-OH-DPAT reduced locomotor activity and pain thresholds and restored them to normal level. Increased pain thresholds were also observed in the sham rats after the chronic administration. These results demonstrated that chronic administration of 8-OH-DPAT reversed the depression-induced decrease in pain sensitivity in rats, suggesting that 5-HT1A receptor may play a role in the depression-associated hypoalgesia.

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Role of AT1 receptors in the renal papillary effects of acute and chronic nitric oxide inhibition

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.274.3.r760 ◽

1998 ◽

Vol 274 (3) ◽

pp. R760-R766 ◽

Cited By ~ 8

Author(s):

M. Clara Ortíz ◽

Lourdes A. Fortepiani ◽

Francisco M. Ruiz-Marcos ◽

Noemí M. Atucha ◽

Joaquín García-Estañ

Keyword(s):

Nitric Oxide ◽

Blood Flow ◽

Angiotensin Ii ◽

Chronic Administration ◽

Acute Administration ◽

Synthesis Inhibitor ◽

Renal Vasoconstriction ◽

Oxide Inhibition ◽

Stimulation Of

Nitric oxide (NO) is a vasodilator substance controlling renal papillary blood flow (PBF) in the rat. In this study we have evaluated the role of AT1 angiotensin II receptors as modulators of the whole kidney and papillary vasoconstrictor effects induced by the acute or chronic inhibition of NO synthesis. Experiments have been performed in anesthetized, euvolemic Munich-Wistar rats prepared for the study of renal blood flow (RBF) and PBF. In normal rats, acute administration of the NO synthesis inhibitor N ω-nitro-l-arginine methyl ester (l-NAME) increased mean arterial pressure (MAP) and decreased RBF and PBF. Either acute or chronic treatment with the AT1 receptor blocker losartan did not modify the decreases in RBF or PBF secondary to l-NAME. In animals made hypertensive by chronic inhibition of NO, basal MAP was higher, whereas RBF and PBF were lower than in the controls. In these animals, acute or chronic administration of losartan decreased MAP and increased both RBF and PBF significantly. These results indicate that, under normal conditions, the decreases in RBF or PBF induced by the acute inhibition of NO synthesis are not modulated by AT1-receptor stimulation. However, the arterial hypertension, renal vasoconstriction, and reduced PBF present in chronic NO-deficient hypertensive rats is partially due to the effects of angiotensin II, via stimulation of AT1-receptors.

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Increase in locomotor activity after acute administration of the nicotinic receptor agonist 3-bromocytisine in rats

European Journal of Pharmacology ◽

10.1016/j.ejphar.2010.02.030 ◽

2010 ◽

Vol 634 (1-3) ◽

pp. 89-94 ◽

Cited By ~ 4

Author(s):

Juan Andrés Abin-Carriquiry ◽

Jessika Urbanavicius ◽

Cecilia Scorza ◽

Marcos Rebolledo-Fuentes ◽

Susan Wonnacott ◽

...

Keyword(s):

Locomotor Activity ◽

Nicotinic Receptor ◽

Receptor Agonist ◽

Acute Administration

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Role of spinal adenosine A1 receptors in the analgesic effect of electroacupuncture in a rat model of neuropathic pain

Journal of International Medical Research ◽

10.1177/0300060519883748 ◽

2019 ◽

Vol 48 (4) ◽

pp. 030006051988374 ◽

Cited By ~ 1

Author(s):

Qin-xue Dai ◽

Lu-ping Huang ◽

Yun-chang Mo ◽

Li-na Yu ◽

Wen-wen Du ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Analgesic Effect ◽

High Performance ◽

Pain Thresholds ◽

Adenosine A1 Receptors ◽

Thermal Pain ◽

Adenosine A1 ◽

Zusanli Acupoint

Objective The aim of this study was to determine the role of spinal adenosine A1 receptors (A1Rs) in the analgesic effects of electroacupuncture (EA) for neuropathic pain. Methods We performed EA for 30 minutes at the zusanli acupoint in the legs of rats with previously induced chronic constriction injuries and observed the mechanical and thermal pain thresholds 1 hour later. We also examined adenosine levels by high-performance liquid chromatography and A1R expression in the L4–6 spinal cord by western blot analysis. We then injected A1R short interfering RNA (AV-shA1RNA) into the L4–6 spinal cord to downregulate A1R expression and re-examined the mechanical and thermal pain thresholds. Results Adenosine levels and A1R expression in the L4–6 spinal cord were increased at 1 hour after EA. In addition, EA exhibited an analgesic effect that was reversed by AV-shA1RNA. Conclusions Our results suggest that EA at the zusanli acupoint elicits an analgesic effect against neuropathic pain, mediated by A1Rs in the spinal cord.

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FFAR1/GPR40 Contributes to the Regulation of Striatal Monoamine Releases and Facilitation of Cocaine-Induced Locomotor Activity in Mice

Frontiers in Pharmacology ◽

10.3389/fphar.2021.699026 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yuko Sadamura ◽

Shanta Thapa ◽

Ryota Mizunuma ◽

Yuki Kambe ◽

Akira Hirasawa ◽

...

Keyword(s):

Fatty Acids ◽

Locomotor Activity ◽

Functional Role ◽

Acute Administration ◽

Wild Type ◽

The Central Nervous System ◽

Free Fatty Acid Receptor ◽

G Protein Coupled ◽

Long Chain

The free fatty acid receptor 1 (FFAR1) is suggested to function as a G protein-coupled receptor (GPR40) for medium-to-long-chain free fatty acids. Previous studies on the expression of FFAR1 revealed that the nigrostriatal region is one of the areas which express abundant FFAR1 mRNA/protein in the central nervous system (CNS). However, the role of FFAR1 in the CNS has been still largely unclarified. Here, we examined a possible functional role of FFAR1 in the control of extracellular concentrations of striatal monoamines and cocaine-induced locomotor activity. Microdialysis analysis revealed that the basal level of extracellular dopamine (DA) was significantly elevated, while the basal serotonin (5-HT) level tended to be reduced in the striatum of FFAR1 knockout (−/−) mice. Interestingly, local application of a FFAR1 agonist, GW9508, markedly augmented the striatal 5-HT release in FFAR1 wild-type (+/+) mice, whereas topical application of a FFAR1 antagonist, GW1100, significantly reduced the 5-HT release. However, the enhanced 5-HT release was completely lost in −/− mice. Although acute administration of cocaine enhanced the locomotor activity in both +/+ and −/− mice, the magnitude of the enhancement was significantly reduced in −/− mice. In addition, intraperitoneal injection of GW1100 significantly decreased the cocaine-induced locomotor enhancement. These results suggest that FFAR1 has a facilitatory role in striatal 5-HT release, and the evoked 5-HT release might contribute to enhance cocaine-induced locomotor activity.

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Role of 5-HT2A receptor agonist microinjected in wistar female rats in the dorsal periaqueductal gray and medial septal area on maternal aggressive behavior

PsycEXTRA Dataset ◽

10.1037/e552682012-139 ◽

2000 ◽

Author(s):

R. M. M. de Almeida ◽

M. Giovenardi ◽

C. Baretta ◽

A. Senger

Keyword(s):

Aggressive Behavior ◽

Receptor Agonist ◽

Periaqueductal Gray ◽

Septal Area ◽

Female Rats ◽

Dorsal Periaqueductal Gray ◽

Medial Septal Area

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Antioxidant Supplementation and Adaptive Response to Training: A Systematic Review

Current Pharmaceutical Design ◽

10.2174/1381612825666190701164923 ◽

2019 ◽

Vol 25 (16) ◽

pp. 1889-1912 ◽

Cited By ~ 8

Author(s):

Rosario Pastor ◽

Josep A. Tur

Keyword(s):

Antioxidant Enzymes ◽

Cellular Response ◽

Recovery Period ◽

Chronic Administration ◽

Antioxidant Response ◽

Redox Status ◽

Exercise Session ◽

Acute Administration ◽

Antioxidant Supplementation ◽

Antioxidant Supplements

Background: Antioxidant supplementation has become a common practice among athletes to theoretically achieve a reduction in oxidative stress, promote recovery and improve performance. Objective: To assess the effect of antioxidant supplements on exercise. Methods: A systematic literature search was performed up to January 2019 in MEDLINE via EBSCO and Pubmed, and in Web of Sciences based on the following terms: “antioxidants” [Major] AND “exercise” AND “adaptation”; “antioxidant supplement” AND “(exercise or physical activity)” AND “(adaptation or adjustment)” [MesH]. Thirty-six articles were finally included. Results: Exhaustive exercise induces an antioxidant response in neutrophils through an increase in antioxidant enzymes, and antioxidant low-level supplementation does not block this adaptive cellular response. Supplementation with antioxidants appears to decrease oxidative damage blocking cell-signaling pathways associated with muscle hypertrophy. However, upregulation of endogenous antioxidant enzymes after resistance training is blocked by exogenous antioxidant supplementation. Supplementation with antioxidants does not affect the performance improvement induced by resistance exercise. The effects of antioxidant supplementation on physical performance and redox status may vary depending on baseline levels. Conclusion: The antioxidant response to exercise has two components: At the time of stress and adaptation through genetic modulation processes in front of persistent pro-oxidant situation. Acute administration of antioxidants immediately before or during an exercise session can have beneficial effects, such as a delay in the onset of fatigue and a reduction in the recovery period. Chronic administration of antioxidant supplements may impair exercise adaptations, and is only beneficial in subjects with low basal levels of antioxidants.

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Ontogeny of locomotor activity and grooming in the young rat: role of dopamine D1 and D2 receptors

European Journal of Pharmacology ◽

10.1016/0014-2999(90)90437-b ◽

1990 ◽

Vol 186 (2-3) ◽

pp. 223-230 ◽

Cited By ~ 39

Author(s):

Sanders A. McDougall ◽

Timothy F. Arnold ◽

Arthur J. Nonneman

Keyword(s):

Locomotor Activity ◽

D2 Receptors ◽

D1 And D2 Receptors ◽

Young Rat

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Chronic Ouabain Prevents Na,K-ATPase Dysfunction and Targets AMPK and IL-6 in Disused Rat Soleus Muscle

International Journal of Molecular Sciences ◽

10.3390/ijms22083920 ◽

2021 ◽

Vol 22 (8) ◽

pp. 3920

Author(s):

Violetta V. Kravtsova ◽

Inna I. Paramonova ◽

Natalia A. Vilchinskaya ◽

Maria V. Tishkova ◽

Vladimir V. Matchkov ◽

...

Keyword(s):

Skeletal Muscle ◽

Single Injection ◽

Chronic Administration ◽

Motor Dysfunction ◽

Hindlimb Suspension ◽

Muscle Disuse ◽

Rat Soleus Muscle ◽

Amp Activated Protein Kinase ◽

Specific Ligand

Sustained sarcolemma depolarization due to loss of the Na,K-ATPase function is characteristic for skeletal muscle motor dysfunction. Ouabain, a specific ligand of the Na,K-ATPase, has a circulating endogenous analogue. We hypothesized that the Na,K-ATPase targeted by the elevated level of circulating ouabain modulates skeletal muscle electrogenesis and prevents its disuse-induced disturbances. Isolated soleus muscles from rats intraperitoneally injected with ouabain alone or subsequently exposed to muscle disuse by 6-h hindlimb suspension (HS) were studied. Conventional electrophysiology, Western blotting, and confocal microscopy with cytochemistry were used. Acutely applied 10 nM ouabain hyperpolarized the membrane. However, a single injection of ouabain (1 µg/kg) prior HS was unable to prevent the HS-induced membrane depolarization. Chronic administration of ouabain for four days did not change the α1 and α2 Na,K-ATPase protein content, however it partially prevented the HS-induced loss of the Na,K-ATPase electrogenic activity and sarcolemma depolarization. These changes were associated with increased phosphorylation levels of AMP-activated protein kinase (AMPK), its substrate acetyl-CoA carboxylase and p70 protein, accompanied with increased mRNA expression of interleikin-6 (IL-6) and IL-6 receptor. Considering the role of AMPK in regulation of the Na,K-ATPase, we suggest an IL-6/AMPK contribution to prevent the effects of chronic ouabain under skeletal muscle disuse.

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Possible Protective Role of Melatonin in Pediatric Infectious Diseases and Neurodevelopmental Pathologies

Journal of Child Science ◽

10.1055/s-0040-1716713 ◽

2020 ◽

Vol 10 (01) ◽

pp. e104-e109

Author(s):

Antonio Molina-Carballo ◽

Antonio Emilio Jerez-Calero ◽

Antonio Muñoz-Hoyos

Keyword(s):

Endothelial Cell ◽

Free Radical ◽

Chronic Administration ◽

Protective Role ◽

Free Radical Scavenger ◽

Radical Scavenger ◽

Energetic Metabolism ◽

Beneficial Effects ◽

Molecular Crosstalk

AbstractMelatonin, produced in every cell that possesses mitochondria, acts as an endogenous free radical scavenger, and improves energetic metabolism and immune function, by complex molecular crosstalk with other intracellular compounds. There is greatly increasing evidence regarding beneficial effects of acute and chronic administration of high melatonin doses, in infectious, developmental, and degenerative pathologies, as an endothelial cell and every cell protectant.

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