title: Methods for the estimation of the excretion of proxicromil and its metabolites in the milk of nursing rat mothers.
abstract: 1. The excretion of proxicromil and its metabolites into the milk of nursing rat mothers and its ingestion by rat pups have been investigated. 2. The methodology employed, hand-milking of the mothers and analysis of suckling rat pups or their stomach contents, has been developed from a review of the scientific literature. The most dependable of the methods used was the analysis of the stomachs of suckling rat pups. This method provided a useful index of radioactivity excreted into milk and allowed calculation of neonate exposure. 3. At a maternal dose level of 20 mg/kg a significant proportion of the dose (1-2%) was excreted into the milk. Analysis of milk taken from rat pup stomachs indicated that both proxicromil (63%) and its hydroxylated metabolites (37%) were present in the milk.
mesh_terms: D000818:Animals; D001711:Biotransformation; D002867:Chromones / Q000378:metabolism*; D005260:Female; D007700:Kinetics; D007774:Lactation; D008892:Milk / Q000032:analysis*; D011247:Pregnancy; D051381:Rats
chemical_list: D002867:Chromones; C020486:proxicromil