Establishment of an Animal Model of Epidural Anesthesia and Sedative Tail-Flick Test for Evaluating Local Anesthetic Effects in Rats

Abstract

Abstract:The tail-flick (TF) test is the most frequently used method to measure pain levels and assess the effects of anesthesia. In this study, we performed the TF test in rats sedated via an indwelling epidural catheter and then examined the effectiveness of this method in evaluating the local anesthetic effects. First, an epidural catheter was inserted into the epidural space, and anesthetic [lidocaine (L) or lidocaine including adrenaline (AL)] or normal saline (NS) was administered. Under sedation, we measured the dose for disappearance of the TF response, time to TF response recovery, onset and regression of local anesthesia, as well as the effect of an added agent on its continuation. The time course of TF latency (% maximum possible effect) in the NS group did not change during the experiment. In the AL group, TF latency increased significantly more than baseline during the 30-min period after injection. This was also significantly higher than the latency in the NS group and the L group. In the L group, the TF latency increased significantly above baseline for 20 min after injection and was significantly higher than that in the NS group. Due to the fact that we were able to detect the effect of local anesthesia onset and regression, as well as the local anesthesia continuation action of an additive agent, in rats sedated via an indwelled epidural catheter, we consider our method to be an improvement over conventional methods.

A novel local anesthetic system: transcriptional transactivator peptide-decorated nanocarriers for skin delivery of ropivacaine

“…Tail-flick (TF) test was applied for evaluating the in vivo anesthetic effect of TAT-RVC/NCs, RVC/NCs, and RVC/IJ 33. Rats were randomly divided into four groups (n=6 each) as follows: 1) TAT-RVC/NCs group; 2) RVC/NCs group; 3) RVC/IJ group; 4) 0.9% saline group.…”

Local anesthetic lidocaine delivery system: chitosan and hyaluronic acid-modified layer-by-layer lipid nanoparticles

“…The TFL test is the most frequently used method to measure pain levels and assess the effects of anesthesia (Ouchi et al, 2013). It uses radiant heat to both measure the latency of the response to thermal noxious stimuli and assess the pain threshold and effect of anesthesia.…”

“…Local anesthetic effects of LA-containing formulations were evaluated by tail-flick latency (TFL) test using a tail-flick measuring device (Ugo Basile, Varese, italy) (Puglia et al, 2011;Ouchi et al, 2013;Caffarel-Salvador et al, 2015). A noxious heat stimulus was applied via a focused, radiant heat light source to the dorsal surface of the tail.…”

On local anesthetic action of some dimethylacetamide compounds

“…To study the local anesthetic activity of dimethylacetamide derivatives, a terminal anesthesia models of the rabbit eye cornea (Regnier 1982) and an infiltration anesthesia method in Agouti guinea pigs (Bulbring and Wajda 1945) were used. The local anesthetic activity of the derivatives on the models of conduction anesthesia was determined by tail-flick test in mice and sciatic nerve blockade model in rats (Ouchi et al 2013). The local irritant effect of the compounds was studied by Setnicar (1966).…”