Abstract
This report deals with an attempt to ascertain the effect of certain pituitary extracts on the rate of ciliary movement of the esophageal and pharyngeal mucosa of healthy frogs (Rana pipiens), weighing 25 g each. The brain and spinal cord were carefully pithed, the lower jaw removed, and the esophagus and stomach exposed by cutting through the pectoral girdle. The pharynx and esophagus were then incised ventrally. The frog was then pinned in a supine position without stretching the area to be observed. Mucus was removed gently by stroking with absorbent cotton saturated with frog saline.
The stimulation of ciliary movement was evaluated by determining the interval during which a mustard seed was transported a constant distance. Fourteen to 20 control determinations preceded the testing of any of the substances. All experiments were conducted at the same room temperature. All the solutions and the frog saline were added at the same rate and the same volume through a pipette. Recovery time was noted in every experiment; the cilia were not rendered permanently non-motile in any experiment.
Pituitrin∗ was the first solution added. Its effect on passage time was recorded at 1, 2 and 3 minute intervals. Pitocin and pitressin were then applied and any comparable results compiled. Forty-five frogs were used in approximately 360 experiments, each result being the average rate of passage of many mustard seeds. Various dilutions of acetic acid were also applied to eliminate the acidity of the pituitrin as a ciliary stimulant.
Table I illustrates the increased motility and its prolongation induced by the topical application of certain concentrations of pituitrin extracts applied to pharyngeal and esophageal mucosa of the frog.
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