| Abstrakt: |
This paper is a report of experiments on the effects of ten aliphatic thiocyanates on contraction rate and dilation of the isolated heart preparation from the roach, B. orientalis. Levy (1) described a physiological saline that would maintain active the isolated hearts of certain dipterous larvae for several hours. Yeager and Hager (2), utilizing a slightly modified Levy's solution, described a method for studying the contraction rate of the isolated insect (B. orientalis) heart, as well as of the Malpighian tubes, under controlled conditions of temperature, pH, osmotic pressure, O2 supply, rate of renewal of saline and concentration of dissolved compound the effect of which is to be determined; they found that under optimal experimental conditions, contractions may continue at a nearly uniform rate for 6 or 7 hours. The method has been further utilized in these experiments. |
