Effects of the sites of injection of aminoguanidine sulfate on developing eggs

The difference in biological effects and distribution when aminoguanidine sulfate (AGS) was injected into different sites of developing eggs was studied. (I) Five mg to 20 mg of AGS were injected once into the air sac (AS), albumen (AL) or yolk sac (YS) from the 4th to the 7th day of incubation. Observation continued up to the 18th day of incubation. In the AS group, total mortality was the highest and external abnormalities were most frequent; however, abnormal findings in liver were infrequent and slight. In the YS and particularly in the AL group, on the other hand, liver abnormalities such as low weight, degeneration, necrosis, increase of mitosis, delay of development and fibrosis were found. These are considered as specific effects of AGS. These frequencies were high when AGS was injected on the 4th and 5th day of incubation. (II) Twenty mg injection of AGS into the AS, AL, or YS on the 5th or 8th day of incubation was made for a distribution study. AGS concentration was determined in the various compartments as various times after injection. Distribution of AGS in the AS group was significantly different from that in the AL and YS groups. The AL and YS groups, however, differed a little. The exact route which AGS reaches from the site of injection to the chick embryos could not be determined, but it is concluded that the albumen is the best site for the injection of AGS to investigate its specific effects on liver.