TY - JOUR
T1 - Capsaicin pretreatment attenuates LPS-induced hypothermia through TRPV1-independent mechanisms in chicken
AU - Nikami, Hideki
AU - Mahmoud, Motamed Elsayed
AU - Shimizu, Yasutake
AU - Shiina, Takahiko
AU - Hirayama, Haruko
AU - Iwami, Momoe
AU - Dosoky, Reem Mahmoud
AU - Ahmed, Moustafa Mohamed
AU - Takewaki, Tadashi
N1 - Funding Information:
The authors are grateful to Goto Chick Company, Gifu, Japan for kindly providing one-day male leghorn chicks. This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Sports and Culture of Japan.
PY - 2008/6/6
Y1 - 2008/6/6
N2 - It has been demonstrated that chicken TRPV1 (transient receptor potential vanilloid of subtype-1) is insensitive to capsaicin (CAP), and therefore, a chicken model is suitable to analyze the CAP-sensitive TRPV1-independent pathway. We elucidated here the possible involvement of the pathway in hypothermia induced by bacterial endotoxin (lipopolysaccharide, LPS) in chickens. Chicks were pretreated with CAP (10 mg/kg, iv) at 1, 2 and 3 days of age to desensitize them towards the CAP-sensitive pathway. An intravenous injection of LPS in 4-day-old chicks caused progressive hypothermia, ending with collapse and 78% mortality within 12 h after injection. The CAP pretreatment rescued the LPS-induced endotoxin shock and hypothermia in chicks. LPS-induced iNOS expression as well as NO production in liver and lung was suppressed by CAP pretreatment. CAP pretreatment also attenuated hypothermia due to exposure of chicks to cold ambient temperature. These findings suggest that a CAP-sensitive TRPV1-independent pathway may be involved in pathophysiological hypothermic reactions through the mediation of NO in chickens.
AB - It has been demonstrated that chicken TRPV1 (transient receptor potential vanilloid of subtype-1) is insensitive to capsaicin (CAP), and therefore, a chicken model is suitable to analyze the CAP-sensitive TRPV1-independent pathway. We elucidated here the possible involvement of the pathway in hypothermia induced by bacterial endotoxin (lipopolysaccharide, LPS) in chickens. Chicks were pretreated with CAP (10 mg/kg, iv) at 1, 2 and 3 days of age to desensitize them towards the CAP-sensitive pathway. An intravenous injection of LPS in 4-day-old chicks caused progressive hypothermia, ending with collapse and 78% mortality within 12 h after injection. The CAP pretreatment rescued the LPS-induced endotoxin shock and hypothermia in chicks. LPS-induced iNOS expression as well as NO production in liver and lung was suppressed by CAP pretreatment. CAP pretreatment also attenuated hypothermia due to exposure of chicks to cold ambient temperature. These findings suggest that a CAP-sensitive TRPV1-independent pathway may be involved in pathophysiological hypothermic reactions through the mediation of NO in chickens.
KW - Capsaicin
KW - Chicken
KW - Cold ambient temperature
KW - LPS
KW - TRPV1
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U2 - 10.1016/j.lfs.2008.04.003
DO - 10.1016/j.lfs.2008.04.003
M3 - Article
C2 - 18474376
AN - SCOPUS:43849085802
SN - 0024-3205
VL - 82
SP - 1191
EP - 1195
JO - Life Sciences
JF - Life Sciences
IS - 23-24
ER -