The l-isomer of methadone possesses opioid activity, whereas the d-isomer is weak or inactive as an opioid. Both d- and l-methadone have been shown to bind to the N-methyl-D-aspartate (NMDA) receptor. To determine whether d-methadone has functional, in vivo NMDA receptor antagonist activity, the antinociceptive effects of d-methadone were evaluated in the rat tail-flick and formalin tests. Cumu...

The analgesic efficacy of cholinergic agonists and anticholinesterase agents has been widely recognized. The analgesic effect obtained by activating cholinergic mechanisms, however, seems to depend on the experimental pain model utilized for its evaluation. The antinociceptive effect of intraspinal neostigmine was examined in rats submitted concurrently to the tail flick and formalin tests. Neo...

  The paragigantocellularis (PGi) nucleus constitutes a large portion of the ventral pontomedullary reticular formation. Neurons within the PGi have been implicated in a variety of functions including cardiovascular regulation, respiratory control, pain and analgesia. Investigators have demonstrated that electrical stimulation and microinjection of L-glutamate into the PGi produce antinocicepti...

Kick out the reticulons to close the envelope The nuclear envelope reforms when tube-forming reticulons are ejected from chromatin-associated ER tubules, say Anderson and Hetzer. The nuclear envelope was once thought to disintegrate into vesicles during mitosis, but growing evidence suggests it is absorbed into the endoplasmic reticulum. Recent in vitro experiments by these authors have shown t...

platanus orientalis l. (platanaceae) is a medicinal tree used in iranian folklore and traditional medicine as a pain and inflammation reliever. in this study, the polyphenolic and total extract of p. orientalis leaves were prepared and their antinociceptive effects were studied in mice using the acetic acid-induced writhing, formalin and light tail flick tests. both hydroalcoholic and polypheno...

Recently, vast studies have been focused on the antinociceptive and anesthetic effects of α2 adrenergic receptors, using specific drugs such as medetomidine and dexmedetomidine. In the present study, we tried to assess the peripheral and central effects of dexmedetomidine in phasic and tonic pain, on rats, using tail flick and formalin tests. Dexmedetomidine, administered intraperitoneally (25,...

Since use of antinoceceptive chemical drugs for relief of pain has many side effects, medical plants seem very noticeable today. Previous findings indicate that Carum Carvi (CC) modulates pain in both animal and human. The present work investigated the effects of hydoalcoholic extract of CC on acute pain in Hot plate and Tail flick models. Albino mice (20-30 g) were used for this study. Hydroal...

Since use of antinociceptive chemical drugs for relief of pain have many side effects, medical plants seem very noticeable today. Previous findings indicate that Foeniculum vulgare (FV) modulates pain in both animal and human. The present work investigated the effects of Hydoalcoholic extract of FV on acute pain in Hot plate and Tail flick models. Albino mice (20-30 gr) were used for this study...