Autoradiographic Distribution of 14C-labeled3H-lmidazo[4,5-f ]quinoline-2- amines in Mice
نویسنده
چکیده
The highly mutagenic heterocyclic amines, 2-amino-3-methylimidazo[4,5-nquinoline (IQ) and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MelQ), are formed during heating of pro tein-rich foods. In order to gain information about the distribution and fate of IQ and MelQ in vivo, a whole-body autoradiographic study of i.v.-injected 14C-labeled IQ and MelQ has been per formed in male NMRI, pregnant NMRI, and female C3H mice. IQ and MelQ showed similar distribution patterns. At short survival times, the autoradiograms were characterized by an accumulation of radioactivity in metabolic and excretory organs (liver, kidney, bile, urine, gastric and intestinal contents, salivary glands, nasal mucosa, and Harder's gland), as well as in lymphomyeloid tissues (bone marrow, thymus, spleen and lymph nodes) and in endocrine and reproductive tissues (adrenal medulla, pancreatic islets, thyroid, hypophysis, testis, epididymis, seminal vesicles, ampulla, and prostate). The liver and kidney cortex were identified as sites of retention of nonextractable radioactiv ity. IQ and MelQ showed a strong affinity for melanin. IQ and MelQ passed the placenta, but no radioactivity was retained in fetal tissues. The results pinpoint the liver as a site of IQand MelQmediated toxicity. Future studies of IQ and MelQ may be guided by and clarify the role of other tissue localizations in the toxicity of IQ and MelQ.
منابع مشابه
Autoradiographic distribution of 14C-labeled 3H-imidazo[4,5-f]quinoline-2-amines in mice.
The highly mutagenic heterocyclic amines, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), are formed during heating of protein-rich foods. In order to gain information about the distribution and fate of IQ and MeIQ in vivo, a whole-body autoradiographic study of i.v.-injected 14C-labeled IQ and MeIQ has been performed in male NMRI, pregnant N...
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