The secretion of bile against pressure.
The secretion of bile against pressure.
复制标题
对抗压力而分泌胆汁。
DOI：
10.1016/s0016-5085(61)80039-5
复制
发表时间：
1961
期刊：
影响因子：
29.4
通讯作者：
J. Y. Thomson
中科院分区：
文献类型：
--
作者：
T. G. Richards;J. Y. Thomson
It has long been known that if the gall bladder is excluded bile may be made to flow from a cannula up a vertical tube until it reaches a limiting height, usually called the" secretory pressure." The height which is reached varies; in the dog it is about 30 em. of bile, in the rat about 16 cm. of bile. It has also been reported that the rate of bile flow up such a column is virtually unvarying until a height some few centimeters from the limit is reached, when the rate begins rapidly to decrease. 1-3 These observations imply either that (1) an unvarying secretory effort is made which, undeterred by a back pressure of, say, 20 cm., is unable to support a pressure of 27 cm., or (2) the secretory effort itself is adjusted, ie, increased, to meet the rising back pressure, so that a steady flow rate results. Recent experiments, outlined below, seem to suggest that the second alternative fits the experimental observations best. When bile flow rate is measured we are, in general, measuring water flow. It is well established that the rates of water flow and of bile salt output are intimately related. Ivy4 and his associates demonstrated this some 15 years ago, and we have ourselves confirmed it by intraportal infusion methods. A certain" basal" flow rate may exist in the theoretical absence of bile salt excretion, but this is small. Further, over any short period of time in the anesthetized animal, the rate of presentation of bile salts to the liver is approximately constant, as is also their rate of excretion. We suggest that to obtain this equilibrium a certain level of substrate or" load" is required by the liver cell, upon which the secretory force acts. In the present outline bile salts have been taken as exemplary of such a substrate. No supposition as to the intimate nature of the process performing work is made, except that normally, under resting conditions, it is not fully engaged. It is in fact considered not to be fully engaged until
