UTERINE EFFECTS OF INTRAVENOUS INJECTIONS OF FLUIDS1

The following study of the intravenous injection of fluids was undertaken with the hope of defining more clearly our knowl-edge of those factors which affect the uterus in the living animal. Doubtless the results are applicable to other forms of smooth muscle existing in the body under normal conditions, Except for experiments in vitro the uterus has received but little pharmacological attention. Employing a method devised in this laboratory (1) for investigations in vivo the following points have been studied by us: 1. Salt action, including the effects of (a) hypotonic solutions: distilled water and 0.3 per cent sodium chiorid; (b) isotonic solutions: 0.9per cent sodlium chiorid and Locke’s solution, NaCl 0.9 per cent, CaCl2 0.024 per cent, KC1 0.042 per cent NaHCO3 0.02 per cent; (c) hypertonic solutions: 3 per cent and 10 per cent sodium chlorid (with supplementary experiments on intestinal injections of 20 per cent sodium sulfate and 20 per cent sodium chiorid) and acacia. 2. Effects of addition or removal of blood. 3. Effects of acid and of alkali. Changes in uterine tone and in the amplitude and rate of the rhythmic contractions weie recorded by kymograph in all of the experiments. Simultaneous records were made of the blood pressure