Effects of General Heat Exposure on the Gastrointestinal Motility of Anesthetized Animals

高温暴露時に食欲不振及び胃腸運動障害がおこる事が知られているがその機序は充分に明らかにされていない。そこで本研究では、麻酔したイヌ及びウサギを約45℃の高温暴露し,高体温に至る過程の胃運動の動態及び、ウサギ空腸片の収縮運動に対する浴液の温度の影響を検討した.麻酔したイヌ及びウサギを高温暴露するとゴム球法で記録された胃運動は直腸温の上昇とともに減弱し,その後の中性温暴露による直腸温の下降とともに回復した.この直腸温変化にともなう胃運動の変化は可逆的であった.ウサギ摘出空腸片の律動収縮は高体温に相当する浴液の温度域において減弱した.以上の結果から,高温暴露による高体温時の胃腸運動の抑制機序には,高体温の胃腸運動調節機構に対する間接的な作用と、胃腸管そのものへの直接作用が考えられる.There are many reports related to the disordered alimentary functions during severe heat stress, but its underlying mechanism is not fully clarified. In the present experiment, therefore, the effects of severe general heat exposure of 45℃ on the gastric motility were investigated in anesthetized dog and rabbit. Gastric movement was recorded with the balloon method. A decrease in gastric motility with the rise of core temperature was observed during general heating, while an increase in the motility with the fall of core temperature was observed after the end of general heating. In the experiment with Magnus method, motility of isolated rabbit\u27s jejunum was also affected by the change in temperature of Tyrode\u27s solution in the bath. From these results, it is suggested that the gastrointestinal motility should be directly and/or indirectly affected by raised core temperature during general heat exposure