BLOOD SULFHYDRYL CHANGES IN METHEMOGLOBINEMIA, A POSSIBLE FACTOR IN PROTECTIVE EFFECTS OF NITRITE AND PARAMINOPROPIOPHENONE

¹ Endocrinology Branch, Division of Physiology, Naval Medical Research Institute, Bethesda, Maryland

The data show that two components of blood sulfhydryl, measured by methods devised for GSH and SH, behaved differently under certain experimental conditions: the concentration of the latter increased while that of the former decreased. This behavior occurred during methemoglobin formation, taking place both in vivo and in vitro when a direct methemoglobin-former (nitrite) was used, but only in vivo when an indirectly-acting agent (PAPP) was used. Some quantitative parallelism between the formation of methemoglobin and the formation of new SH groups was demonstrated. Alloxan, a poor methemoglobin former, significantly reduced the concentration of blood GSH without appreciably affecting the SH level.