Publications by authors named "Robert J Naylor"

Cannabidiol (CBD) has been shown to inhibit gastrointestinal (GI) transit in pathophysiologic in vivo models, while having no effect in physiologic controls. The actions of the precursor of CBD, cannabidiolic acid (CBDA), have not been investigated in the GI tract. The actions of these phytocannabinoids on the contractility of the GI tract of Suncus murinus were investigated in the current study.

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The effect of cannabinoids on motion-induced emesis is unknown. The present study investigated the action of phytocannabinoids against motion-induced emesis in Suncus murinus. Suncus murinus were injected intraperitoneally with either cannabidiol (CBD) (0.

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The chemotherapeutic drug cisplatin is associated with severe gastrointestinal toxicity that can last for several days. A recent strategy to treat the nausea and emesis includes the combination of a 5-HT3 receptor antagonist, a glucocorticoid, and an NK1 receptor antagonist. The present studies explore the use of the selective noradrenaline reuptake inhibitors, (R)-sila-venlafaxine, (R,R)-reboxetine and (S,S)-reboxetine to prevent cisplatin (5 mg/kg, i.

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In the present study we evaluated the role of 5-HT(1A) receptors in mediating the inhibitory action of 8-OH-DPAT, a 5-HT(1A) receptor agonist, in motion sickness in Suncus murinus. 8-OH-DPAT (0.1 mg/kg, i.

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The study investigated the role of endothelin (ET) and the ET receptor subtypes ET(A) and ET(B) in mediating longitudinal contraction in the mouse proximal and distal colon. Cumulative concentration-response curves to a range of ET agonists (ET-1, ET-2, ET-3, (Ala(1,3,11,13)) ET and IRL 1620) were established by administering concentrations ranging from 0.01 nM to 0.

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5-HT3 receptors.

Curr Drug Targets CNS Neurol Disord

February 2004

5-HT(3)-receptor antagonists are highly selective competitive inhibitors of the 5-HT(3)-receptor with negligible affinity for other receptors. They are potent, rapidly absorbed and easily penetrate the blood-brain barrier; metabolized by the cytochrome P450-system with half-life varying from 3-10 hours. The compounds investigated so far do not modify normal behaviour in animals or man and are well tolerated over wide dose ranges, the most common side effects being headache or constipation.

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The study was undertaken to investigate the 5-HT receptor mediating the inhibitory effect of 5-HT on peristalsis in the guinea-pig isolated ileum. The facilitatory and inhibitory effects were measured as the decrease and increase, respectively, in the intraluminal pressure required to trigger peristalsis. In the presence of 5-HT(2/3&4) receptor antagonists ketanserin (0.

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In the present study, we investigated the effect of 5-hydroxytryptamine (5-HT) and 5-HT receptor agonists and antagonists on motion sickness in Suncus murinus, and the possibility that the emetic stimulus of 5-HT can alter the sensitivity of the animals to the different emetic stimulus of motion sickness. 5-HT (1.0, 2.

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Epidemiological evidence suggests that nonsteroidal, anti-inflammatory drugs (NSAIDs) may retard the progression of Alzheimer's disease (AD). In the present study, we have chronically treated adult (4-5 months old) and aged (20+ months) rats with water adulterated with aspirin, and examined spatial learning in a swim maze. Adult rats (n=40) and aged rats (n=20) were divided into separate groups assigned to receive either normal drinking water or water with 2 mg/ml of aspirin dissolved in it.

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