PT  - JOURNAL ARTICLE
AU  - G. N. STEWART
AU  - J. M. ROGOFF
TI  - THE SPONTANEOUS LIBERATION OF EPINEPHRIN FROM THE ADRENALS
DP  - 1916 Sep 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 479--524
VI  - 8
IP  - 9
4099  - http://jpet.aspetjournals.org/content/8/9/479.short
4100  - http://jpet.aspetjournals.org/content/8/9/479.full
SO  - J Pharmacol Exp Ther1916 Sep 01; 8
AB  - 1. The spontaneous liberation of epinephrin has been studied (in the cat) by means of the (denervated) eye reactions and the blood pressure changes caused by blood from the adrenals when permitted to pass into the circulation from a pocket of the vena cava in which it has been collected in known amounts and for known periods of time. 2. Since the blood is not withdrawn from the vessels the uncertainty introduced by the rapid development in the blood of pressor bodies which simulate the action of epinephrin on some of the objects most generally used in biological tests for that substance, is eliminated. 3. The simultaneous observation of the eye reactions greatly aids in the interpretation of the blood pressure curves when the amount of epinephrin is small. 4. The approximate assay (without withdrawal of blood) of the epinephrin in the blood collected in the cava pocket from the adrenals, by the injection of varying doses of adrenalin generally presents no difficulty. It must be repeated from time to time in the course of an experiment when the condition of the animal changes. The amount of epinephrin spontaneously liberated in cats was found to vary in different experiments within a rather narrow range considering the differences in the conditions (from 0.0008 to 0.0028 mgm. per minute per animal, or from 0.0003 to 0.001 mgm. per minute per kilo of animal. 5. After section of both sympathetic trunks in the thorax near the diaphragm, including the major splanchnics, the spontaneous liberation of epinephrin is completely abolished. Division of the major splanchnics in the abdomen does not necessarily cause total cessation of the secretion in all cats. In one animal a detectable amount was still liberated but the liberation was entirely stopped when all the fibers coming to the semilunar ganglion were cut. 6. The fal of blood pressure caused by section of both splanchnics has nothing to do with the failure of the adrenals to liberate epinephrin. For when the nerves of the right gland are alone divided and the left adrenal vein clipped, the blood collected from the right adrenal in the cava pocket yields no epinephrin reactions on release of the pocket. 7. Although, as is known, cats survive indefinitely the removal moval of one adrenal and division of the nerve supply of the other, no detectable epinephrin was found in the blood coming from the remaining adrenal 5 weeks after the operation. Good reactions were obtained on massaging the gland. 8. No increase in the epinephrin liberation was detectable when sensory nerves (brachial) were stimulated. If any increase was produced by asphyxia in our observations it was very slight.