62 KANSAS UNIVERSITY SCIENCE BULLETIN. 



Na2HP04 solutions stimulate as a rule only the force of heart 

 action. The blood pressure, heart rate, as well as respiratory 

 activities, are generally decreased or unaltered. 



Solutions of NaOH proved more stimulating to cardiac force 

 and blood pressure than any of the other solutions that were 

 employed. They were depressing to cardiac rate and respira- 

 tory activity, except in strong solutions they increased the rate 

 of respiration. They affect the center that controls the force 

 of the heart-beat oppositely from what they do the center 

 which governs the respiratory force. Like other alkaline solu- 

 tions, they may exert their influence by favoring oxidation. 



Urea solutions, except the strongest, are quite indifferent to 

 the functions under consideration. A 4m solution increases 

 the force of both the cardiac and respiratory activities ; possi- 

 bly through the OH ions that are set free when dissociation oc- 

 curs. 



Weak HCl solutions produce initial stimulations for a brief 

 period in cardiac and respiratory force and blood pressure, but 

 depress the rate, and a stronger, m/8, solution is toxic for 

 cardiac but less so for respiratory activity. 



Weak solutions of NH4CI are indifferent. An m/8 has a 

 slight augmenting effect on blood pressure and the expiratory 

 phase, while an m% solution depresses blood pressure and 

 cardiac rhythm, but heightens the force of the respiratory 

 mechanism for a short time. 



Following the injection of strong Na2S04 solutions the force 

 of respiration and heart action and height of blood pressure 

 is increased, while the rate is unchanged. The addition of a 

 weak solution of CaCh is favorable. 



The effect of a weak solution of BaCk is increased force of 

 cardiac and respiratory rhythm and a rise of blood pressure. 

 Diastolic and expiratory phases are prolonged. The solutions 

 are more toxic than other salts of the same concentration, and 

 the toxicity is overcome by CaCk. 



Injections of distilled water produce transient stimulating 

 effects in the force of cardiac contractions and blood pressure, 

 and depress the rate. 



Weak solutions of NaH2P04 accelerate the rate and force of 

 heart and respiratory action. Diastole and inspiration are 

 prolonged and toxic solutions are neutralized by Na2HP04. 

 'A consideration of the results tabulated in the foregoing 



