TY - JOUR
T1 - Effects of lowering ambient temperature on pain-related behaviors in a rat model of neuropathic pain
AU - Sato, Jun
AU - Morimae, Hirohumi
AU - Takanari, Keisuke
AU - Seino, Yusuke
AU - Okada, Taro
AU - Suzuki, Minemori
AU - Mizumura, Kazue
N1 - Funding Information:
Acknowledgements We wish to thank Dr. K. Koga and Mr. Y. Ohta for their technical assistance. This work was partly supported by Grants-in-Aid for Scientific Research from the Japanese Ministry of Education, Science and Culture, and the Kato Ryutaro Foundation at Nagoya University. Additional support was received by the Ground Research for Space Utilization program promoted by NASDA and the Japan Space Forum.
PY - 2000
Y1 - 2000
N2 - To clarify the mechanism by which changes in chronic pain are induced by cold environments, rats rendered neuropathic by a chronic constriction injury (CCI) to the sciatic nerve were exposed to low ambient temperature (LT; 7°C decrease from 22°C) in a climate-controlled room. LT exposure aggravated pain-related behaviors in CCI rats, i.e., decreased the threshold to von Frey hair and paw pressure stimulation, prolonged the duration of foot withdrawal to pinprick stimulation, and increased the cumulative duration of guarding posture. Lumbar sympathectomy (SYX) did not inhibit LT-induced augmentations of pain-related behaviors in CCI rats. LT exposure decreased the skin temperatures of both hind paws to the same degree in the sham-operated control and SYX rats, while in the CCI and SYX + CCI rats it caused a larger temperature decrease in the injured paw than in the uninjured one. These results indicate that LT exposure augments abnormalities in pain-related behaviors of neuropathic rats, and also suggest that sympathetic nervous activity is not a predominant factor in the augmenting mechanism.
AB - To clarify the mechanism by which changes in chronic pain are induced by cold environments, rats rendered neuropathic by a chronic constriction injury (CCI) to the sciatic nerve were exposed to low ambient temperature (LT; 7°C decrease from 22°C) in a climate-controlled room. LT exposure aggravated pain-related behaviors in CCI rats, i.e., decreased the threshold to von Frey hair and paw pressure stimulation, prolonged the duration of foot withdrawal to pinprick stimulation, and increased the cumulative duration of guarding posture. Lumbar sympathectomy (SYX) did not inhibit LT-induced augmentations of pain-related behaviors in CCI rats. LT exposure decreased the skin temperatures of both hind paws to the same degree in the sham-operated control and SYX rats, while in the CCI and SYX + CCI rats it caused a larger temperature decrease in the injured paw than in the uninjured one. These results indicate that LT exposure augments abnormalities in pain-related behaviors of neuropathic rats, and also suggest that sympathetic nervous activity is not a predominant factor in the augmenting mechanism.
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U2 - 10.1007/s002210000451
DO - 10.1007/s002210000451
M3 - Article
C2 - 10985679
AN - SCOPUS:0033860377
VL - 133
SP - 442
EP - 449
JO - Experimental Brain Research
JF - Experimental Brain Research
SN - 0014-4819
IS - 4
ER -