Ballintijn C M
Respir Physiol. 1985 Apr;60(1):59-74. doi: 10.1016/0034-5687(85)90039-8.
The activity pattern of the adductor muscles of the gill filaments has been determined with E.M.G. techniques and analysed in relation to the activity of the respiratory pump muscles, the respiratory movements and the hydrostatic pressures in buccal and opercular cavities. The gill filament adductor muscles contract twice during a normal respiratory cycle. First during the transition from the contraction to the expansion phase and for a second time at the end of the expansion phase. These two contractions serve different purposes. The first 'primes' the opercular pump for the start of the next expansion phase in the following way. At the end of the contraction phase, the final adduction of the opercula results in a positive pressure in the opercular cavities. If this pressure persisted until the start of the expansion, it would make the opercular suction pump inoperative, because it would blow away the flexible opercular flap which, as a passive valve, seals the widening opercular slit during abduction. Filament adduction at the transition from contraction to expansion, however, by lowering the resistance of the gill curtain, allows water to escape from the opercular cavities through the mouth and so reduces opercular pressure to zero before expansion starts. The second contraction of the filament adductor muscles, at the end of the expansion phase, occurs when the opercular flap separates from the body of the fish, opening the opercular slit. At this moment, there is a considerable negative pressure in the opercular cavity. Nevertheless, inflow of water through the opercular slit is negligible, because flow reversal is counteracted by the kinetic energy of the normal water flow from the buccal to the opercular cavities. This process is significantly facilitated by a reduction in gill resistance through filament adduction. In the cough, a burst of filament adductor activity occurs during the intermediate expansion. It then increases water flow velocity over the gills by lowering the gill resistance and also brings the filaments in such a position that the water flows parallel to their surface, which facilitates the flushing off of foreign matter.
利用肌电图技术测定了鳃丝内收肌的活动模式，并结合呼吸泵肌肉的活动、呼吸运动以及口腔和鳃腔中的静水压力进行了分析。在正常呼吸周期中，鳃丝内收肌收缩两次。第一次在从收缩阶段过渡到扩张阶段时，第二次在扩张阶段结束时。这两次收缩具有不同的目的。第一次收缩以下列方式为下一个扩张阶段开始时的鳃盖泵“预充能”。在收缩阶段结束时，鳃盖的最终内收会在鳃腔中产生正压。如果这个压力一直持续到扩张开始，它会使鳃盖抽吸泵无法工作，因为它会吹开柔软的鳃盖瓣，而鳃盖瓣作为一个被动瓣膜，在鳃盖外展时密封扩大的鳃盖裂缝。然而，在从收缩到扩张的过渡阶段，鳃丝内收通过降低鳃幕的阻力，使水从鳃腔通过口腔流出，从而在扩张开始前将鳃腔压力降至零。鳃丝内收肌的第二次收缩发生在扩张阶段结束时，此时鳃盖瓣与鱼体分离，打开鳃盖裂缝。此时，鳃腔内存在相当大的负压。然而，通过鳃盖裂缝的水流入量可以忽略不计，因为水流逆转被从口腔到鳃腔的正常水流的动能抵消。通过鳃丝内收降低鳃阻力，这一过程得到了显著促进。在咳嗽时，在中间扩张阶段会出现一阵鳃丝内收肌活动。然后，它通过降低鳃阻力增加了鳃上的水流速度，还使鳃丝处于这样一种位置，即水流平行于它们的表面，这有助于冲走异物。
