Comment on Meier's “Prenatal Anoxia and Irradiation: Maternal-Fetal Relations”

Abstract

Biologists such as Wilson (Wilson, Jordan, & Brent, 1953; Wilson 8: Kart, 1951), Lengerova (1957) in Prague, and Neifakh (1957) in the USSR have certainly demonstrated that direct irradiation of the fetus outside the maternal cavity causes deficits in weight, increase in mortality, and measurable morphologic changes. In addition, Neifakh estimates the maternal contribution to be 596, as judged by biological measures, which at best are crude in comparison with behavioral measures. Sharp's study (1961) is most relevant and should be compared with Meier's 1961 report ( 1961a), a reference which Furchtgott ( 1962) appears to have overlooked in commenting on Meier's review ( 1961b). Sharp irradiated nine litters which were divided into three groups: (Group 1) no~adiated controls, (Group 2) radiation of mother only, and (Group 3) mother plus fetal radiation. Meier (1961) worked with 19 litters divided into groups treated as Groups 2 and 3 above, plus a fourth group in which radiation was of the fetus only. He suggests that maternal influence may be estimated from a comparison of Groups 3 and 4 with values of Group 2 falling midway between these. On the oeher hand, if the radiation damage is determined directly by the amount received by the fetus rather than by the mother, the groups will be ordered 3, 4, and 2 from the greatest to least damaging to the fetus. Sharp's rats were placed in a 14-unit maze at 115 days of age; the testing lasted 22 days. Meier's rats were somewhat younger, being 70 to 80 days of age. They were exposed to the Lashley and Dashiell mazes for approximately 10 days of testing. An important difference in the daca analysis was Meier's separation of male and female data, the sex difference having been shown by T. Graham (personal communication, 1960) to be significant in radiation learning. No significant differences in time scores were found for the females but the scores tended in the direction of maternal influence. The maze scores were significantly different for the males and were clearly in the direction predicted for maternal influence. It is indeed unfortunate that a normal control group was not included. Sharp's rats received irradiation at the rate of 35 r per day from the 10th through 17th day of gestation, to a total of 280 r. Meier's rats received a single dose of 200 r, litters being irradiated 2 to 14 days before parcurition. Sharp's daca on locomotion behavior reveal no significant performance dif