the selected parts of four medicinal plants, achillea millefolium, hibiscus rosasinensis, linum usitatissimum and pluchea lanceolata were extracted in absolute methanol to determine their analgesic activity. analgesic activity was assessed on intact mice by tail flick latency via the tail immersion method. the analgesic activities of these plant extracts were compared with acetylsalicylic acid ...

Objective- To evaluate antinociceptive efficacy of pre- versus post-incisional morphine, tramadol and meloxicam using tail-flick test in an incisional model of pain in rats. Design- Prospective, randomized experimental study. Animals- Eighty, adult, male Wistar rats weighing 250–300 g. Procedures- Animals were randomly divided into eight groups to receive pre- or post-incisional (tail skin i...

It is now well established that the analgesic actions of opioids can be modified by "anti-analgesic" or "antiopioid" peptides, among them cholecystokinin (CCK). Although the focus of much recent work concerned with CCK-opioid interactions has been at the level of the spinal cord, CCK also acts within the brain to modify opioid analgesia. The aim of the present study was to characterize the acti...

In this study, we characterized the role of delta-1 and delta-2 opioid receptors in the ventromedial medulla (VMM) in the modulation of thermal nociception. Male Sprague-Dawley rats were prepared with an intracerebral guide cannula aimed at the nucleus raphe magnus or nucleus reticularis gigantocellularis pars alpha. Microinjection of the delta-1 opioid receptor agonist [D-Pen2,D-Pen5]enkephali...

In this study, we examined whether Sprague-Dawley rats obtained from two different vendors, Harlan and Sasco, differ with respect to the types of alpha-2 adrenoceptors in the spinal cord that mediate antinociception. This hypothesis was tested using two alpha-2 adrenoceptor agonists, dexmedetomidine and ST-91, which are relatively selective for alpha-2A and alpha-2B adrenoceptors, respectively,...

Zinc is concentrated in the dorsal horn of the spinal cord and has been proposed to alter excitability of primary afferent C-fibers, structures believed to be important in nociceptive transmission. Based on the inhibitory effect of zinc on the activity of various other neurotransmitters that play a role in nociception, we tested the hypothesis that zinc modulates pain transmission. To test this...

Resveratrol has been widely investigated for its potential health properties, although little is known about its mechanism in vivo. Previous studies have indicated that resveratrol produces antinociceptive effects in mice. Calcium channels and calcium/caffeine-sensitive pools are reported to be associated with analgesic effect. The present study was to explore the involvement of Ca2+ channel an...