The effect of post-burn local hyperthermia on the reducing burn injury: the possible role of opioids.
OBJECTIVE
This paper studied the effect of post-burn local hyperthermia on burn induced injury.


METHODS
A second-degree burn injury was induced on the right and left flanks of Balb/c mice. Thirty-two burn wounds were divided into four groups. Opioid receptor blocking was done for groups 3 and 4 by intra-peritoneal administration of Naloxone (NLX) 30 min before the thermal injury. Local hyperthermia (45 degrees C, 30 s) was applied only for the burn wounds of groups 2 and 4. Twenty-four hours after burn injury, the burned wounds were assessed for the level of iNOS (by immunohistochemistry) and the number of hair follicles (as an indicator of tissue injury).


RESULTS
The wounds that received hyperthermia (group 2) had significantly more hair follicles (p < 0.001) compared to the control wounds (group 1). There was no significant difference between the number of hair follicles and acute inflammation of group 1 and group 3 (NLX + burn). Group 4 (NLX + burn + hyperthermia) had significantly fewer hair follicles compared to group 1 (p < 0.001), group 2 (p < 0.001) and group 3 (p < 0.001). The level of iNOS in groups 1, 3 and 4 was not significantly different but significantly more than group 2 (p < 0.001, p < 0.001 and p < 0.001, respectively).


CONCLUSIONS
The results showed that local hyperthermia after second degree burn decreased the tissue injury and iNOS expression. It is also concluded that endogenous opioid response may have a key role in the above mentioned effects of post-burn local hyperthermia.
Shahabi
Shahram
S
Department of Immunology, School of Medical Sciences, Tarbiat Modarres University, Tehran, Iran. shahabsh@modares.ac.ir
Hashemi
Mahmud
M
Hassan
Zuhair Muhammad
ZM
Javan
Mohammad
M
Bathaie
Seiedeh Zahra
SZ
Toraihi
Taki
T
Zakeri
Zahra
Z
Ilkhanizadeh
Behrouz
B
Jazani
Nima Hosseini
NH
D000818:Animals; D002056:Burns / Q000201:enzymology / Q000473:pathology / Q000628:therapy*; D018859:Hair Follicle / Q000473:pathology; D006979:Hyperthermia, Induced / Q000379:methods*; D051379:Mice; D008807:Mice, Inbred BALB C; D009270:Naloxone / Q000008:administration & dosage; D009292:Narcotic Antagonists / Q000008:administration & dosage; D009336:Necrosis; D052247:Nitric Oxide Synthase Type II / Q000032:analysis; D014945:Wound Healing / Q000502:physiology
D009292:Narcotic Antagonists; D009270:Naloxone; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse