TY - JOUR
T1 - Role of metabolites in propanil-induced hemolytic anemia
AU - McMillan, David C.
AU - Bradshaw, Timothy P.
AU - Hinson, Jack A.
AU - Jollow, David J.
N1 - Funding Information:
’ This work was supported by a grant from the U.S. Public Health Service (HL-30038), and was presented in part at the Fourth International Symposium on Biological Reactive Intermediates, Tuscan, AZ, 1990. * To whom correspondence should be addressed at Department of Pharmacology, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425-225 1.
PY - 1991/8
Y1 - 1991/8
N2 - Hemolytic anemia and methemoglobinemia induced by exposure to certain arylamines, such as aniline and dapsone, are known to be mediated by their N-hydroxylamine metabolites. The arylamide propanil (3,4-dichloropropionanilide), a herbicide used extensively in rice fields, is also thought to induce methemoglobinemia through the action of metabolites. However, the hemolytic potential of this compound has not previously been reported. The present studies were undertaken to determine the hemolytic potential of propanil, and, if positive, the role of metabolites in this hemotoxicity. The survival of previously administered 51Cr-labeled erythrocytes in rats was reduced in a dose-dependent manner by ip administration of both propanil and its deacylated metabolites, 3,4-dichloroaniline (ED50 for both ca. 1.8 mmol/kg). When labeled erythrocytes were exposed in vitro to propanil or 3,4-dichloroaniline and then readministered to rats, no decrease in erythrocyte survival was observed, which indicated that these compounds were not direct-acting hemolytic agents. In contrast, erythrocyte survival was markedly reduced by ip administration or in vitro exposure to N-hydroxy-3,4-dichloroaniline. In addition, N-hydroxy-3,4-dichloroaniline was detected in the blood of propanil-treated rats in amounts sufficient to account for the hemolytic activity of the parent compound. These data indicate that N-hydroxy-3,4-dichloroaniline mediates propanil-induced hemolytic anemia, and that occupational exposure to propanil may result in an increased risk of hemolytic episodes.
AB - Hemolytic anemia and methemoglobinemia induced by exposure to certain arylamines, such as aniline and dapsone, are known to be mediated by their N-hydroxylamine metabolites. The arylamide propanil (3,4-dichloropropionanilide), a herbicide used extensively in rice fields, is also thought to induce methemoglobinemia through the action of metabolites. However, the hemolytic potential of this compound has not previously been reported. The present studies were undertaken to determine the hemolytic potential of propanil, and, if positive, the role of metabolites in this hemotoxicity. The survival of previously administered 51Cr-labeled erythrocytes in rats was reduced in a dose-dependent manner by ip administration of both propanil and its deacylated metabolites, 3,4-dichloroaniline (ED50 for both ca. 1.8 mmol/kg). When labeled erythrocytes were exposed in vitro to propanil or 3,4-dichloroaniline and then readministered to rats, no decrease in erythrocyte survival was observed, which indicated that these compounds were not direct-acting hemolytic agents. In contrast, erythrocyte survival was markedly reduced by ip administration or in vitro exposure to N-hydroxy-3,4-dichloroaniline. In addition, N-hydroxy-3,4-dichloroaniline was detected in the blood of propanil-treated rats in amounts sufficient to account for the hemolytic activity of the parent compound. These data indicate that N-hydroxy-3,4-dichloroaniline mediates propanil-induced hemolytic anemia, and that occupational exposure to propanil may result in an increased risk of hemolytic episodes.
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U2 - 10.1016/0041-008X(91)90290-U
DO - 10.1016/0041-008X(91)90290-U
M3 - Article
C2 - 1871773
AN - SCOPUS:0025826192
SN - 0041-008X
VL - 110
SP - 70
EP - 78
JO - Toxicology and Applied Pharmacology
JF - Toxicology and Applied Pharmacology
IS - 1
ER -