Introduction
Recently I had the opportunity of receiving Noradrenaline with. the trade name of Levophed. Thus it was possible for me to make observations and to compare it with adrenalin regarding. its pre3sor action on the rabbit and dog.
Method:
Experimental animals were divided into two groups, a bleeding group and a control group. Bleeding was done by severing the carotid-vein.
Pre-calculated amounts of Noradreraline and Adrenaline were given groups of animals checking their B. P. before and- after medication. During these procedure. changes of B.P. were observed. Total brood volume was estimated as-1/13 of body weight in the rabbit and 1/10 in the dog. In the bleeding group, it was, planned to bane then bled to the equivalent of 1/3 of the total blood volume in the rabbit and to 1/4 in the dog. However, in some animals the B.P.dropped to 40mm Hg. before the amount of blood loss reached the planned amount. In these groups, blood letting had to be stopped when B.P. was 40mm Hg.
Result:
1). In the control group of rabbits, the duration of pressor effect of noradrenaline was lorger than adrenaline (1.5 times) with. of no apparent difference in the desire of initial elevation of blood pressure.
2). In the bleeding group of rabbits the pressor effect of noradrenalin was remarkably prolonged. However, the degree of B. P. elevations in the group of rabbits and both deg nee and the durat ton of pressor effect in the group of dogs´ were more significant with nonadrenalire than adrenaline.
3). In the rabbits were given adrenaline.
the B.P. dropped below the pre-medication level in the terminal phase of both groups.
4). In the bleeding group of dogs, the same result of pressure elevation and prolongation were obtained by the alternate use of-them two drugs just after the elevated B.P. dropped to the previous level.
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