Does inflammation induced by ultraviolet B and heat rekindling alter pain-related behaviour in rats?

作者：Smith Melissa; Taylor Collette; Weerasinghe Nirosha; Koutsikou Stella; Lumb Bridget; Murrell Jo^*

来源：Veterinary Anaesthesia and Analgesia, 2016, 43(5): 579-585.

DOI：10.1111/vaa.12349

• burrowing
• heat rekindling
• pain
• rat
• ultraviolet B

ObjectiveTo investigate whether induction of the ultraviolet B and heat rekindling (UVB/HR) model alters burrowing behaviour in rats.
Study designRandomized, blinded, prospective experimental study.
AnimalsSixteen adult male Wistar rats weighing 250-300g.
MethodsIn the UVB/HR group (n=8), UV irradiation was delivered to the heel area of the right plantar pelvic limb paw at a dose of 1000mJcm(-2), using a narrow-band UVB light source. Twenty-four hours later, heat rekindling was performed by placement of a feedback-controlled thermode set at a constant temperature of 45 degrees C over the area of UVB irradiation for 5minutes. Both interventions were carried out under pentobarbital anaesthesia. The sham' group (n=8) was anaesthetized only. In the burrowing test, rats were housed singly for 2hours in cages furnished with a burrow filled with sand. The amount of sand remaining in the burrow after 2hours was weighed and the amount displaced from the burrow calculated. The burrowing test was carried out for two consecutive days prior to UVB irradiation (day 0), on day 1 prior to HR, on days 2 and 3 after UVB exposure and at equivalent time points in the sham group.
ResultsRats in the sham group burrowed means (SD) of 2429 (73) g and 2358 (124) g of sand on days -2 and 3, respectively, while those in the UVB/HR group burrowed 2460 (26) and 2419 (58) g on days -2 and 3, respectively. There was no significant effect of treatment on the amount of sand burrowed at any time point.
Conclusions and clinical relevancePain associated with UVB/HR model induction is below the threshold required to affect rat burrowing behaviour and therefore questions the face validity of UVB/HR as a translational model of inflammatory pain.

• 出版日期2016-9