在沙漠干热环境中负重行军者血浆中NO和NOS与生理应激的关系

目的探讨沙漠干热环境负重行军者NO和一氧化氮合酶（NOS）与生理应激的关系。方法60名战士在沙漠干热环境中负重15kg分别以3．5和5．0km／h行军1、2、3h，检测试验组和对照组战士血浆中NO含量和NOS活力、心律增值、肛温增值和积热指数。结果所有行军时间组NO（17．26～23．28μmol／L）含量均明显低于对照组（31．84μmol／L）（P〈0．05），心率增值（7．6—23．9次／min）均明显高于对照（1．2次／min）（P〈0．05）。15kg负重3．5km／h行军时，行军3h组NO（17．26μmol／L）含量明显低于行军1h组（22．62μmol／L）和2h组（23．10μmol／L）（P〈0．05）；行军1h组NOS（47．35U／L）活力明显高于行军3h组（40．90U／L）和对照组（40．89U／L）（P〈0．05）；行军3h组肛温增值（0．17℃）明显高于行军1h组（0．02oC）和对照组（0．00℃）（P〈0．05）；行军1和2h组积热指数（-18．9±18．31kJ／m2）明显低于行军3h组（22．67kJ／m2）和对照组（0．41kJ／m2）（P〈0．05），行军3h组积热指数明显高于对照组（P〈0．05）。15kg负重5．0km／h行军时，行军2h组NOS（39．44U／L）活力明显低于对照组（40．89U／L）和其他行军时间组（34．23—40．43U／L）（P〈0．05）；行军1h组（23．9μmin）和3h组（21．3μmin）心率增值明显高于行军2h组（7．60μmin）（P〈0．05）；机体肛温随行军时间的延长而增高；各行军组积热指数（51．04～71．12kJ／m2）明显高于对照组（0．41kJ／m2）。结论在沙漠干热环境中行军者血浆中NO含量和NOS活力与热应激有关，沙漠干热环境劳动强度以不超过重度为宜，持续劳动时间不应超过2h。

Relation between Nitric Oxide and Nitric Oxide Synthase with physiological stress of marcher with load in dry heat environment of desert

[ Objective ] To explore the relation between nitric oxide （ NO ） and nitric oxide synthase （ NOS ） with physiological stress of marchers with load in dry heat environment of desert. [ Methods]60 soldiers with 15 kg marched in dry heat environment of des- ert at speed of 3.5 and 5.0 km/h for 1, 2 or 3 hours. NO, NOS, heart rate, rectal temperature and body heat storage index （ BHSI） of experimental and control group were detected. [ Results ] NO content in experimental groups （ 17.26-23.28 μmol/L） were lower than that in control group （ 31.84μmol/L ） （ P 〈 0.05 ） , the heart rates （ 7.6-23.9 beat/min ） were signifieantly higher than those in the control group （ 1.2 beat/min ） （ P 〈 0.05 ）. When marching at speed of 3.5 km/h, the NO content of 3 hours group （ 17.26 μ mol/L） was lower than that of 1 hour group （22.62 μmol/L） and 2 hours group （23.1 p, mol/L） （ P 〈0.05 ） ; the NOS vitality of 1 hour group （47.35 U） was higher than that in 3 hours group （40.91 U/L）and the control group （40.89 U/L） （ P 〈 0.05） ; the rectal temperature of 3 hours group （ 0.17 ℃ ） was obviously higher than that of 1 hour group （ 0.02 ℃ ） and the control group （ 0.00 ℃ ） （ P 〈0. 05 ） ; BHSI of 1 hour and 2 hours （ - 18.94- - 18.3 KJ/m2 ） were significantly less than that of 3 hours （ 22.67 KJ/m2 ） and control group （0.041 KJ/m2 ） / P 〈 0.05 ） ; BHSI of 3 hours was obviously more than that of the control group （ P 〈 0.05 ）. When marching at speed of 5.0 km/h, the NOS vitality of 2 hours group （ 39.44 U/L） was lower than that of other hours group （34. 23-40.43 U/L） and control group （40. 89 U/L） （P 〈0. 05） ; the heart rates of 1 hour group （23.9 beat/min） and 3 hours group （21.3 beat/min） were higher than that of 2 hours group （7.6 beat/min） （P 〈 0.05） ; the rectal temperatures increased with the increasing of marching time; the BHSI of experimental groups （51.04-71.12 KJ/m2）