[Effect of preemptive intrathecal lornoxicam on foot swelling of formalin test in rats].
OBJECTIVE
To investigate the anti-inflammatory effect of preemptive intrathecal Lornoxicam on foot swelling of formalin test in rats.


METHODS
Eighteen healthy male adult Sprague-Dawley (SD) rats (about 250 g) were randomized into 3 groups: intrathecal solvent group (group S, solvent 20 microL), intramuscular Lornoxicam group (group IM, Lornoxicam 300 microg/20 microL) and intrathecal Lornoxicam group (group IT, Lornoxicam 300 microg/20 microL). After measuring the basic volumes of the left hind paws, rats were injected with corresponding solution intrathecally or intramuscularly, and followed by an intra-plantar administration of 100 microL of 5% formalin 10 minutes later. The volumes of left hind paws were measured again at 10 min, 30 min, 1 h, 2 h, 3 h, 4 h, 24 h after formalin injection.


RESULTS
There was no statistical difference of weights or basic volumes among three groups. At 10 min after formalin injection, the left hind paw volume of group IT [(1.53 +/- 0.06) mL] were smaller than that of group S [(1.67 +/- 0.09) mL], P=0.039, but there was no statistically difference between group IT and group IM [(1.65 +/- 0.06) mL]. At 30 min after formalin injection, the left hind paw volume of group S [(1.88 +/- 0.88) mL] was larger than that of group IM [(1.77 +/- 0.05) mL, P<0.05] and group IT [(1.61 +/- 0.06) mL, P<0.01]. The feet swelling degree of group IT was less than that of group IM, P<0.05. At 1 h, 2 h and 3 h after formalin injection, the left hind paw volume of group S was similar to that of group IM, and the volume of group IT was smaller than the other two groups. At 4 h and 24 h after formalin injection, there were no statistic differences of the left hind paw volume among the three groups.


CONCLUSIONS
At 10 min to 3 h after formalin injection, swelling of rat feet induced by formalin was alleviated by preemptive intrathecal Lornoxicam.
Yang
Bang-xiang
BX
Laboratory of Anesthesiology and Critical Diseases, West China Hospital, Sichuan University, Chengdu 610041, China.
Chen
Xu
X
Song
Li
L
Liu
Hui
H
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy*; D005534:Foot Diseases / Q000139:chemically induced / Q000188:drug therapy; D005557:Formaldehyde; D007278:Injections, Spinal; D008297:Male; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy; D010894:Piroxicam / Q000008:administration & dosage / Q000031:analogs & derivatives*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D000894:Anti-Inflammatory Agents, Non-Steroidal; D010894:Piroxicam; D005557:Formaldehyde; C059451:lornoxicam