Sasser L B, Jarboe G E
J Nutr. 1980 Aug;110(8):1641-7. doi: 10.1093/jn/110.8.1641.
The purpose of this study was to measure intestinal absorption and retention of cadmium in the newborn pig and to compare data from the pig, rat and guinea pig, three species that differ greatly in their ability to absorb macromolecules at birth. Newborn pigs were administered a single oral dose of 50 muCi of 115mCd (0.20 mCi/mg Cd) 24 hours after birth and killed at intervals between 1 and 14 days after dosing. Cd absorption and gastrointestinal retention were then determined; these data were compared with similar data from the rat and guinea pig. The cumulative Cd absorption was about 4.0, 5.0 amd 23% of the dose in the day-old pig, rat and guinea pig, respectively. The residence time of Cd in the intestinal tract was longer in the rat than in the pig or guinea pig, the 50% excretrion time being 15, 8, and 5 days in the rat, pig and guinea pig, respectively. Cd absorption in the neonate appears to be a two-step process: mucosal uptake of Cd from the lumen, probably by pinocytosis, followed by transfer of a portion of this Cd into the body. This transfer process is similar, but does not entirely coincide with changes associated with protein absorption in the neonate.
本研究的目的是测定新生仔猪肠道对镉的吸收和潴留情况，并比较猪、大鼠和豚鼠这三种在出生时吸收大分子能力差异很大的物种的数据。新生仔猪在出生后24小时口服单剂量50微居里的115mCd（0.20微居里/毫克镉），给药后1至14天内每隔一段时间处死。然后测定镉的吸收和胃肠道潴留情况；将这些数据与大鼠和豚鼠的类似数据进行比较。新生仔猪、大鼠和豚鼠对镉的累积吸收量分别约为给药剂量的4.0%、5.0%和23%。镉在大鼠肠道内的停留时间比猪或豚鼠长，大鼠、猪和豚鼠的50%排泄时间分别为15天、8天和5天。新生儿对镉的吸收似乎是一个两步过程：镉可能通过胞饮作用从肠腔被黏膜摄取，随后一部分镉转移到体内。这个转移过程是相似的，但并不完全与新生儿蛋白质吸收相关的变化一致。
