Development and Characterization of a Novel, Anatomically Relevant Rat Model of Acute Postoperative Pain

Abstract

Acute pain following inguinal hernia repair can be difficult to treat. Here we report, for the first time, the development of a novel, anatomically relevant rat model to facilitate improved understanding and treatment of acute postoperative pain following inguinal hernia repair.

Characterization of the Affective Component of Acute Postoperative Pain Associated with a Novel Rat Model of Inguinal Hernia Repair Pain

“…Open field testing was carried out as described previously and performed under dim light (7 lux). The surgery-induced deficits in both home cage and open field vertical locomotor activity observed previously [6] were again evident in the present study, confirming that this phenotype is retained on a normal light:dark cycle. The surgery-induced reduction in home cage activity was attenuated by carprofen, corroborating our previous results [6] and confirming that the surgery-induced locomotor impairment is pain-related.…”

“…For the present study, animals were placed on a traditional light–dark cycle (lights on at 08:00 h) in their home cage as this was more compatible with mPEAP testing which was performed at 100 lux and during the animals’ light phase. This contrasts with our previous report on the model where animals were kept on a reverse light–dark cycle to provoke a high baseline of locomotor activity in the early postoperative period, thereby giving a bigger window over which to see ‐induced locomotor deficits. Open field testing was carried out as described previously and performed under dim light (7 lux).…”

Contribution of diacylglycerol lipase β to pain after surgery

“… 33 , 39 , 47 , 48 We employed postsurgical locomotor activity as a readout of spontaneous, non-evoked pain because similar to humans, postsurgical pain in rodents is associated with reduced mobility (locomotion and rearing). 4 , 7 , 28 , 34 In our hands, the clinically efficacious analgesic ketoprofen partially rescued the incision-induced decrease in locomotor activity, indicative of analgesia. In contrast, KT109 failed to alter postsurgical locomotor or rearing activity, which reflects its modest effects upon postsurgical PGE 2 levels and weak analgesic effects.…”

FAAH inhibition attenuates TLR3-mediated hyperthermia, nociceptive- and anxiety-like behaviour in female rats

“…Home cage locomotor activity was assessed using the Opto-M3 Dual Axis system (Columbus Instruments, Columbus, OH) as previously described [34,35]. Following poly I:C/saline injection, animals were returned to their home cage and horizontal activity (total beam breaks) was recorded and presented as activity during the light phase (0-8 h post poly I:C/saline) and the dark phase (nocturnal activity: 14-22 h post poly I:C/saline).…”