Comperatore C A, Stephan F K
Department of Psychology, Florida State University, Tallahassee 32306-1051.
J Biol Rhythms. 1987 Fall;2(3):227-42. doi: 10.1177/074873048700200306.
The electrical activity of the antrum and proximal duodenum was recorded simultaneously with bar pressing for food in various feeding conditions. During restricted feeding (RF; food available from 1200 to 1600 hr; lights-on from 0800 to 2000 h), large-amplitude slow potentials of duodenal origin were observed 3-5 hr preceding food access. These potentials occurred in short trains at irregular intervals of approximately 1 min and appeared to be associated with the active phase of the migrating motility complex. At least 8-10 days on RF were required before these irregular contractions (ICs) reliably preceded food access. The distribution of ICs showed a circadian variation during food deprivation, and transients lasting 4-6 days were observed in response to 6- or 8-hr phase delays of food access. These observations suggest that ICs are modulated by a circadian mechanism. On the average, the increase in ICs occurred about 2 hr earlier than bar pressing in anticipation of food, and there was no specific relation between individual ICs and bar pressing. However, bar pressing frequently occurred 0.5 min or longer after an increase in electromyogram (EMG) amplitude. Unreinforced bar pressing was never observed during a quiescent EMG.
在各种进食条件下，同时记录胃窦和十二指肠近端的电活动以及按压食物杠杆的情况。在限制进食（RF；12:00至16:00可获取食物；08:00至20:00开灯）期间，在进食前3 - 5小时观察到十二指肠起源的大幅度慢电位。这些电位以短串形式出现，间隔约1分钟，不规则，似乎与移行性运动复合波的活跃期有关。在这些不规则收缩（ICs）可靠地先于进食出现之前，至少需要8 - 10天的限制进食。在禁食期间，ICs的分布呈现昼夜变化，并且在进食时间延迟6或8小时时，观察到持续4 - 6天的短暂变化。这些观察结果表明，ICs受昼夜节律机制调节。平均而言，ICs的增加比预期进食时按压食物杠杆早约2小时出现，并且单个ICs与按压食物杠杆之间没有特定关系。然而，在肌电图（EMG）幅度增加后0.5分钟或更长时间，经常会出现按压食物杠杆的情况。在静息EMG期间从未观察到无强化的按压食物杠杆行为。
