Clinical and experimental pharmacology & physiology
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Clin. Exp. Pharmacol. Physiol. · Sep 2010
Exercise training attenuates anaphylactic venoconstriction in rat perfused liver, but does not affect anaphylactic hypotension in conscious rats.
1. Exercise training attenuates circulatory shock due to haemorrhage, endotoxin or heatstroke. However, it remains unknown whether exercise training attenuates anaphylactic shock. ⋯ In contrast, exercise training did not attenuate either anaphylactic hypotension or portal hypertension in conscious rats. 4. In conclusion, exercise training attenuates the anaphylaxis-induced presinusoidal constriction in rat isolated perfused livers, independent of NO production. However, this action is not evident in conscious rats and exercise training does not affect anaphylactic hypotension in conscious rats.
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Clin. Exp. Pharmacol. Physiol. · Aug 2010
Antithrombotic management of ischaemic stroke and transient ischaemic attack in China: a consecutive cross-sectional survey.
1. Little is known about the prevention of secondary stroke in China. In the present study, we assessed the status of antithrombotic management of stroke patients in clinics across China. 2. ⋯ Being older (OR 0.70; 95% CI 0.50-0.99) and having a severe disability (OR 0.68; 95% CI 0.49-0.97) were associated with lower odds of receiving antiplatelet therapy. 4. Based on the survey results, adherence to guidelines for antithrombotic management in neurological clinics in China is poor. The main reasons contributing to the less than optimal management of stroke patients include negative attitudes among neurologists, a lack of medical insurance, a lower income and being elderly and/or severely disabled.
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Clin. Exp. Pharmacol. Physiol. · Aug 2010
Functional impact of the hyperpolarization-activated current on the excitability of myelinated A-type vagal afferent neurons in the rat.
1. The hyperpolarization-induced, cation-selective current I(h) is widely observed in peripheral sensory neurons of the vagal and dorsal root ganglia, but the peak magnitude and voltage- and time-dependent properties of this current vary widely across afferent fibre type. 2. Using patch clamp investigations of rat isolated vagal ganglion neurons (VGN) identified as myelinated A-type afferents, we established a compendium of functional correlates between changes in membrane potential and the dynamic discharge properties of these sensory neurons as a result of the controlled recruitment of I(h) using the current clamp technique. 3. ⋯ Application of the selective hyperpolarization-activated cyclic nucleotide gated (HCN) channel blockers ZD7288 (10 micromol/L) or CsCl (1.0 mmol/L) abolished I(h) and all of the aforementioned functional correlates. In addition to reducing the excitability of the A-type VGN to step depolarizing currents. 6. Because there is increasing evidence that the HCN channel current may represent a valid target for pharmacological intervention, the quantitative relationships described in the present study could potentially help guide the molecular and/or chemical modification of HCN channel gating properties to effect a particular outcome in VGN discharge properties, ideally well beyond merely selective blockade of a particular HCN channel subtype.
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Clin. Exp. Pharmacol. Physiol. · May 2010
Peripheral antinociceptive effect of 2-arachidonoyl-glycerol and its interaction with endomorphin-1 in arthritic rat ankle joints.
1. Both cannabinoid and opioid receptors are localized at the peripheral level, and drugs acting on these receptors may produce antinociception after topical administration; however, the effect of endogenous ligands at these receptors is poorly understood. Our goal was to determine the antinociceptive potency of the endogenous cannabinoid 2-arachidonoyl-glycerol (2-AG), and its interaction with endomorphin-1 (EM1) at joint level in the rat inflammation model. 2. ⋯ The effects of EM1 and 2-AG were prevented by mu-opioid and cannabinoid 1 receptor antagonists, respectively. The ED(25) value for the combination (98 (CI: 80-112) microg) did not differ significantly from the value of 2-AG; however, the largest dose combination produced a significantly higher effect than the ligands by themselves. 4. Our data showed that 2-AG was an effective antinociceptive ligand at joint level, and its combination with EM1 produced long-lasting, effective antinociception.
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Clin. Exp. Pharmacol. Physiol. · Apr 2010
Inhibitory effect of fucoidan on nitric oxide production in lipopolysaccharide-activated primary microglia.
1. Microglial activation plays an important role in the pathogenesis of neurodegenerative diseases by producing various pro-inflammatory cytokines. Microglia-derived nitric oxide (NO) is critical for the lipopolysaccharide (LPS)-induced selective loss of dopaminergic neurons. 2. ⋯ Fucoidan (125 microg/mL) also suppressed phosphorylation of p38 and extracellular signal-regulated kinase (ERK) by approximately 50%, but not that of c-Jun N-terminal kinase. 5. The results provide the first evidence that fucoidan has a potent inhibitory effect against LPS-induced NO production by microglia. The results also suggest that this inhibitory action of fucoidan involves suppression of p38 and ERK phosphorylation.