Arjamaa O, Talo A
Acta Physiol Scand. 1981 Oct;113(2):233-7. doi: 10.1111/j.1748-1716.1981.tb06888.x.
There occur strong spontaneous contractions in the avian oviduct. These contractions are considered to effect the locus of the ovum during ovum transport. It is not known how there contractions are regulated and no comprehensive description of the concentrations exists. When a transversal strip cut from the magnum part of the oviduct was first stretched to a length of about 275% Lo (Lo = length in situ) and then released to a length of Lo at a rate of 1.7 min/min, it was found that contractions were different during release from those found during stretch. The rate of stretch and release, and the change in length, were physiological. i.e. they can be recorded under normal transport circumstances in vitro. The amplitude of active tension was usually larger during release than during stretch at comparable lengths. The duration of a single contraction on the other hand was significantly longer during stretch than during release, but the number of contractions was smaller. The total area of active tension was 1.34 times greater during release than during stretch. Passive tension always increased with stretching, while during release passive tension was smaller. It is discussed whether the changes are of membraneous origin or if they result directly from the contractile apparatus.
禽类输卵管会出现强烈的自发收缩。这些收缩被认为在卵子运输过程中影响卵子的位置。目前尚不清楚这些收缩是如何调节的，也没有关于其浓度的全面描述。当从输卵管峡部切下的横向条带首先被拉伸至约275%Lo（Lo = 原位长度）的长度，然后以1.7分钟/分钟的速度释放至Lo长度时，发现释放过程中的收缩与拉伸过程中的收缩不同。拉伸和释放的速度以及长度变化都是生理性的。也就是说，它们可以在体外正常运输情况下记录下来。在可比长度下，主动张力的幅度通常在释放时比拉伸时更大。另一方面，单次收缩的持续时间在拉伸时明显长于释放时，但收缩次数较少。主动张力的总面积在释放时比拉伸时大1.34倍。被动张力总是随着拉伸而增加，而在释放过程中被动张力较小。文中讨论了这些变化是源于膜还是直接由收缩装置引起。
