PT  - JOURNAL ARTICLE
AU  - A. R. CUSHNY
AU  - J. A GUNN
TI  - THE ACTION OF SERUM ON THE PERFUSED HEART OF THE RABBIT
DP  - 1913 Sep 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 1--19
VI  - 5
IP  - 1
4099  - http://jpet.aspetjournals.org/content/5/1/1.short
4100  - http://jpet.aspetjournals.org/content/5/1/1.full
SO  - J Pharmacol Exp Ther1913 Sep 01; 5
AB  - 1. When the isolated heart of the rabbit is perfused with Ringer's solution, the addition of serum produces well-marked changes in the cardiac contractions. Those changes may be divided into (a) a preliminary stage of stimulation in which the contractions are augmented and usually accelerated, and (b) a subsequent stage of depression in which the contractions are weakened and slowed, in which heart-block may occur, and which may eventually lead to arrest of the heart. In either stage a return of the normal contractions can be produced by reperfusion with Ringer's solution. 2. Serum produces also a reduction of the flow through the coronary vessels. This is not a consequence of the alterations in the heart's contractions. On the contrary, evidence has been brought forward to show that these alterations in the heart beat are in large part the result of the diminished flow through the vessels. The primary stimulant action of serum may be due in part to a direct action of serum on cardiac muscle. 3. The diminution in the coronary flow is due to a direct action on the coronary vessels and not to the increased viscosity of the perfused solution. 4. The effects described on the heart and its vessels are produced not only by a foreign serum but also by egg albumen, starch solution, and even the animal's own serum or plasma. For these and other reasons, it is suggested that the effects are due to an abnormal condition of the heart and its vessels, which is produced when that organ is isolated and perfused for some time with Ringer's solution. In other words, the phenomenon arises from changes in the organ from the normal and not from the formation of a poison in the fluid used for perfusion.