Gastric Absorption of 3,4-Benzpyrene

Lux UV with a Philora HPW 19@5-watt mercury vapor lamp). The intensity and the penetration power of the blue fluorescence was estimated by using an arbitrary gradation (cf. Fig. @). However, spectroscopic estimations were not made, and therefore it is unknown whether the blue fluores cence in the tissues depends on unchanged BP or on its blue fluorescent metabolites. Bearing this in mind, reference is made only to the absorption of BP in the present work. About 600 healthy adult stock mice of both sexes, employed for several years in our studies, were used. Some experiments were conducted with C3Hmicewithsimilar results.Additional investiga tions were carried out with young cats, weighing @5O—35Ogm. All theanimalswere kept undersimilar laboratory conditions, and the diet was sufficient and balanced, particularly with respect to vita mins A and B. No pathologic changes, including spontaneous tumors, were encountered. The ani mals fasted at least 1@hours before administration of BP, as well as during the entire experiment. Thus, the stomach was nearly empty, and dilu tion of the solutions instilled was prevented, ex cept that due to the normal gastric secretion. The amount of solutions administered by stomach tube was O.@cc. per mouse and @.O cc. per cat. The animals were killed by decapitation 5, 15, 30, or 60 minutes, or @4—48 hours after feeding. The or gans, after fixation in 10 per cent neutral formalin solution (from 1 to 10 hours), were cut on the freezing microtome at 10 @ thickness, mounted in anhydrous glycerol, and examined (at least 5 hours after autopsy). Control observations were made on unfixed and unmounted specimens. Im.. mersion of the organs in the fixative solution for less than about 10 hours produced no essential changes in the localization and in the intensity of the blue fluorescence in the tissues. Other speci mens were imbedded in paraffin and stained in the usual manner for comparison. Because carcinogenic hydrocarbons are fat soluble, it seems likely that the mechanism of their Adenocarcinoma of the glandular region of the stomach has not been induced by feeding the fat soluble carcinogenic hydrocarbons to mice and rats, although carcinoma of the forestomach and/or of the small intestine may occur (1, 4, @3, @8).It has been suggested that the glandular