Breve reseña sobre la farmacología de los cannabinoides / Brief review on the pharmacology of cannabinoids

Intensa resulta la controversia entre los que promueven el uso de los cannabinoides con fines terapéuticos y quienes consideran que es temprana aún la introducción de estos en la clínica, por sus efectos deletéreos para la salud humana en las diferentes etapas y condicionales del desarrollo biológico. Paralelamente se debate, entre las autoridades encargadas de velar por la salud de sus conciudadanos, la polémica de legalizar o no el consumo de la Cannabis sativa en cualquiera de sus formas y derivados naturales. Ambas polémicas han fundamentado el estudio de todas las formas de presentación y consumo de esta planta, así como de sus derivados sintéticos dados sus efectos sobre la salud de enfermos y sanos. En esta breve reseña se exponen aspectos relevantes de su farmacología, debido al interés y enorme caudal de información generado por un sinnúmero de investigadores dedicados al estudio de dicha planta y sus derivados

The controversy among those that promote the use of cannabinoids with therapeutic aims is intense and who consider that it is still early for their introduction in the clinic, due to their lethal effects for the human health in the different stages and conditionals of the biological development. In parallel it is debated, among the authorities in charge of looking after the health of their fellow citizens, the polemic of legalizing or not the consumption of the Cannabis sativa in any of their forms and natural derived. Both polemics have based the study of all the forms of presentation and consumption of this herb, as well as of its synthetic derived due to their effects on the health of sick and healthy people. In this brief review outstanding aspects of their pharmacology are exposed, due to the interest and enormous flow of information generated by a large number of investigators dedicated to the study of this herb and its derived elements

Participation of cannabinoid receptors in peripheral nociception induced by some NSAIDs

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used extensively to control inflammatory pain. Several peripheral antinociceptive mechanisms have been described, such as opioid system and NO/cGMP/KATP pathway activation. There is evidence that the cannabinoid system can also contribute to the in vivo pharmacological effects of ibuprofen and indomethacin. However, there is no evidence of the involvement of the endocannabinoid system in the peripheral antinociception induced by NSAIDs. Thus, the aim of this study was to investigate the participation of the endocannabinoid system in the peripheral antinociceptive effect of NSAIDs. All experiments were performed on male Wistar rats (160-200 g; N = 4 per group). Hyperalgesia was induced by a subcutaneous intraplantar (ipl) injection of prostaglandin E2 (PGE2, 2 μg/paw) in the rat’s hindpaw and measured by the paw pressure test 3 h after injection. The weight in grams required to elicit a nociceptive response, paw flexion, was determined as the nociceptive threshold. The hyperalgesia was calculated as the difference between the measurements made before and after PGE2, which induced hyperalgesia (mean = 83.3 ± 4.505 g). AM-251 (80 μg/paw) and AM-630 (100 μg/paw) were used as CB1 and CB2 cannabinoid receptor antagonists, respectively. Ipl injection of 40 μg dipyrone (mean = 5.825 ± 2.842 g), 20 μg diclofenac (mean = 4.825 ± 3.850 g) and 40 μg indomethacin (mean = 6.650 ± 3.611 g) elicited a local peripheral antinociceptive effect. This effect was not antagonized by ipl CB1 cannabinoid antagonist to dipyrone (mean = 5.00 ± 0.9815 g), diclofenac (mean = 2.50 ± 0.8337 g) and indomethacin (mean = 6.650 ± 4.069 g) or CB2 cannabinoid antagonist to dipyrone (mean = 1.050 ± 6.436 g), diclofenac (mean = 6.675 ± 1.368 g) and indomethacin (mean = 2.85 ± 5.01 g). Thus, cannabinoid receptors do not seem to be involved in the peripheral antinociceptive mechanism of the NSAIDs dipyrone, diclofenac and indomethacin.