Intraplantar morphine depresses spinal c‐Fos expression induced by carrageenin inflammation but not by noxious heat

  title={Intraplantar morphine depresses spinal c‐Fos expression induced by carrageenin inflammation but not by noxious heat},
  author={Prisca Honore and Jaroslava Buritova and Jean Marie Besson},
  journal={British Journal of Pharmacology},
1 We have studied the effects of intraplantar administration of the same doses of morphine on intraplantar carrageenin (6 mg 150 μ***l−1 of saline) and noxious heat (52°C for 15 s) induced spinal c‐Fos expression and inflammation. 2 Intraplantar carrageenin, in awake rats, induced numerous Fos‐like immunoreactive (Fos‐LI) neurones in the dorsal horn of L4‐L5 lumbar segments of the spinal cord and extensive peripheral oedema. At 1 h 30 min, Fos‐LI neurones were preferentially located in the… 

Endomorphin-1 reduces carrageenan-induced Fos expression in the rat spinal dorsal horn

Results provided a strong evidence for involvement of mu opioid receptor in peripheral analgesia, particularly in inflammation pain, in rats.

Effects of local anaesthetics on carrageenan-evoked inflammatory nociceptive processing in the rat.

Intraplantar infiltration with lignocaine and bupivacaine before carrageenan transiently limited signs of inflammatory pain but did not prevent them.

Intrathecally Injected Morphine Inhibits Inflammatory Paw Edema: The Involvement of Nitric Oxide and Cyclic-Guanosine Monophosphate

The idea that morphine can act on opioid receptors at the spinal level to produce antiedematogenic effect is supported, and that the NO/cGMP pathway seems to be an important mediator in this effect.



Reduction of carrageenin oedema and the associated c‐Fos expression in the rat lumbar spinal cord by nitric oxide synthase inhibitor

There is a strong correlation between the reduction of the number of Fos‐LI neurones and the oedema by l‐NAME, clearly demonstrating a predominant role of peripheral NO in the development of one of the signs of carrageenin inflammation.

Systemic morphine suppresses noxious stimulus-evoked Fos protein-like immunoreactivity in the rat spinal cord

The effect of systemic morphine on Fos-like immunoreactivity (FLI) evoked in the formalin test, a widely used model of persistent pain, and the dose-response relationship of morphine-induced suppression of FLI varied in different laminae indicate that analgesia from systemic opiates involves differential regulation of nociceptive processing in subpopulations of spinal nocICEptive neurons.

Morphine or U‐50,488 suppresses fos protein‐like immunoreactivity in the spinal cord and nucleus tractus solitarii evoked by a noxious visceral stimulus in the rat

It is suggested that morphine and U‐50,488 have comparable effects on the transmission of visceral nociceptive messages by spinal neurons, but differentially affect the autonomic response to noxious visceral stimuli.