PT  - JOURNAL ARTICLE
AU  - A. S. LOEVENHART
AU  - W. E. GROVE
TI  - STUDIES ON THE PHARMACOLOGICAL ACTION OF OXIDIZING SUBSTANCES
DP  - 1911 Nov 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 101--130
VI  - 3
IP  - 2
4099  - http://jpet.aspetjournals.org/content/3/2/101.short
4100  - http://jpet.aspetjournals.org/content/3/2/101.full
SO  - J Pharmacol Exp Ther1911 Nov 01; 3
AB  - 1. Improved methods for making and purifying iodbenzoic, iodosobenzoic, and iodoxybenzoic acids are described. 2. The local action of the free acids and their sodium salts are described. The results show that of the sodium salts, those ofiodbenzoic and iodoxybenzoic acids are mild, while that of iodosobenzoic acid is extremely irritating when injected subcutaneously or intraperitoneally. 3. It is shown that sodium iodosobenzoate and iodoxybenzoate, in dilute solution, have a peculiar metallic taste very much like that of hydrogen peroxide and it is suggested that the active oxygen confers upon all of these compounds their peculiar taste. 4. Solutions of sodium iodosobenzoate and iodoxybenzoate immediately oxidize haemoglobin to oxyhaemoglobin. 5. The peroxidase of the blood enables sodium iodosobenzoate to oxidize phenolphthalin to phenolphthalein; in other words, it can furnish oxygen for this peroxidase reaction in the same manner that hydrogen peroxide does. 6. Sodium iodosobenzoate and sodium iodoxybenzoate, when injected intravenously, do not exercise a destructive action on the blood to any extent. Leucocytosis of a moderate grade may be noted. 7. In order to elicit their characteristic effects on the circulation and respiration the salts must be injected intravenously. 8. On the Circulation: Sodium iodbenzoate is but very slightly active, causing a rise of arterial blood pressure. The mechanism by which this is brought about was not determined. Sodium iodosobenzoate usually causes a marked and long continued fall of blood pressure. During the time that the blood presure shows the greater part of the fall, the heart rate and amplitude are hardly affected. The salt causes dilatation of a loop of intestine when the splanchnic nerves are intact, but not after they are cut. It does not affect the caliber of blood vessels by peripheral action. Hence it depresses the vaso-motor center. At certain stages the salt increases the cardiac output and we believe this to be the mechanism involved in the rise of blood pressure occasionally noted. Sodium iodoxybenzoate acts similarly to the iodosobenzoate on the circulation, but its action is not so marked. It causes a rise of blood pressure in a larger per cent of the cases than iodosobenzoate and is less depressing on the heart. The usual fall of blood pressure is due to depression of the vaso-motor center. 9. On the Respiration: Sodium iodbenzoate contains no active oxygen and in the doses we employed it does not affect the rate or depth of the respiration. Sodium iodosobenzoate and sodium iodoxybenzoate have about the same effect on the respiration. They both cause cessation of the respiration in repose, in dogs, cats and rabbits. The best results are obtained with cats. The period of apnoea usually begins within a few seconds after starting the injection and lasts from a few seconds up to 2 or 3 minutes and is terminated by spontaneous return of the respiration. Apnoea may come on several minutes after the last injection. Apnoea is more easily produced by the drugs after section of the vagi, but this is not essential. Apnoea may occur with a rising or a falling blood pressure and is independent of it. During the apnoea there is usually a fall of blood pressure while the pulse rate remains normal. 10. Of the medullary centers, the respiratory center is the most sensitive to sodium iodosobenzoate and iodoxybenzoate. The vaso-motor center is next and the cardio-inhibitory center is not affected by them. 11. It is pointed out that the remarkable effect of sodium iodosobenzoate and iodoxybenzoate on the respiration and also their effect on the vaso-motor center, must be due to activity of the oxygen combined with the iodine in these compounds.