Rubin B K, Ramirez O, King M
Pulmonary Defense Research Group, University of Alberta, Edmonton, Canada.
J Appl Physiol (1985). 1990 Aug;69(2):424-9. doi: 10.1152/jappl.1990.69.2.424.
To better understand the frog palate model of mucociliary transport, we measured the transport rate of mucus (MTR) from the leopard frog, Rana pipiens, and from the bullfrog, R. catesbeiana, recorded the stability of the MTR over a period of hours and days and over the course of 1 yr, and measured the viscoelasticity, percent solid composition, and spinnability (filance) of mucus from both species. Bullfrog mucus was less rigid than leopard frog mucus (log G* at 1 rad/s 2.09 vs. 2.61; P less than 0.01) and had a higher viscosity-to-elasticity ratio (tan delta at 1 rad/s 0.36 vs. 0.26; P less than 0.05). It also had a lower solids content (8.71 vs. 13.72%; P = 0.02), and there was a trend to lower spinnability for bullfrog mucus (filance 26.7 vs. 33.5 mm). These data suggest that bullfrog mucus has viscoelastic properties similar to normal mammalian respiratory mucus and leopard frog mucus has viscoelasticity similar to sputum samples. MTR was significantly slower in the winter than in the summer months (17 vs. 30 mm/min; P less than 0.0001). Although the leopard frog palate could be used for at least 7 consecutive days without exhaustion, bullfrog palates could be used for only 5 days. Palates of either species could generally be tested for 6 h/day without a significant decrease in MTR. These data clarify some of the sources of variability in the use of this system and suggest methods of standardization.
为了更好地理解青蛙腭部黏液纤毛运输模型，我们测量了豹蛙（Rana pipiens）和牛蛙（R. catesbeiana）黏液的运输速率（MTR），记录了数小时、数天以及1年时间内MTR的稳定性，并测量了两种蛙类黏液的粘弹性、固体成分百分比和可纺性（拉丝性）。牛蛙黏液的硬度低于豹蛙黏液（1弧度/秒时的对数G*为2.09对2.61；P小于0.01），且具有更高的黏度与弹性比（1弧度/秒时的损耗因子tan δ为0.36对0.26；P小于0.05）。其固体含量也较低（8.71%对13.72%；P = 0.02），并且牛蛙黏液的可纺性有降低的趋势（拉丝长度26.7对33.5毫米）。这些数据表明，牛蛙黏液的粘弹性特性类似于正常哺乳动物呼吸道黏液，而豹蛙黏液的粘弹性类似于痰液样本。冬季的MTR明显慢于夏季月份（17对30毫米/分钟；P小于0.0001）。虽然豹蛙腭部可连续使用至少7天而不衰竭，但牛蛙腭部只能使用5天。两种蛙类的腭部通常每天可测试6小时，而MTR不会显著下降。这些数据阐明了该系统使用中一些变异性的来源，并提出了标准化方法。
