990 SHORE ET AL. Table 3 IN VIVO RELATIVE INCORPORATION OF “C— Phe INTO 4C- Phe A.LF, OF FETUSES FROM STARVED SHAM- AND X-IRRADIATED RATS g {c) Treatment Starved and sham irradiated Relative in- “3 corporation (b) x 1077 dis/min/g fetus of 4C— Phe Number fetal (a) fe) into MC Phe (a) per weight, “C-Phe "C—Phe (Nf ALF, Litter Iltter mg A.LF, A.S.F. {d) + (e) (a/(h R § 12 12 158 137 28.8 26.8 §5.6 1.4 84.4 78.2 0.341 0.343 u v Ww x Y¥ 10 14 il il 14 131 135 135 154s: 121 . 27,3 19.9 23,0 30.3 20,7 64.9 36.7 40.1 44,2 39.8 82.2 56.6 63.1 74.5 60.3 0.332 0.352 0.365 0.407 0,343 T 12 144 30,8 57.6 88.4 0.348 X S.E, Starved and irradiated z AA ll 13 125 104 21.1 24.0 AG 13 136 26.4 AB AC AD AE AF 14 15 12 12 li 116 118 103 120 120 BEST AVAILABLE COPY 22.9 24.7 18,3 21.6 11.4 49.5 §1.8 70.6 75,5 46,5 72.9 46.5 49.5 38,0 45.8 27.6 0,354 0,010 0.299 0.317 69.4 74,2 §6,3 67,4 39,0 0.330 0,333 0,325 0,320 0.292 0,362 Be Roh X 0,322 analysis of variance of the data in Tables 2 and 3 showed statistically significant effects due to both X radiation (p < 0.05) and food and water deprivation (p < 0.05). No indication of interaction between these two factors was detected; thus the effects are additive. The multiple-range test!® indicated that incorporation in the starved and sham-irradiated and starved and X irradiated groups was significantly less than incorporation in the respective fed groups (p < 0.05). Further, it indicated that “C—Phe incorporation in the starved ir- radiated group was significantly lower than the incorporation observed in any of the other experimental groups (p< 0.05). Thus, these data indicate that, in the fetus present in its intrauterine environment, X radiation causes a small but s{gnificant decrease in the incorporation of “C—Pheinto protein per unit weight of fetal tissue. Irradiated fetuses increased in weight from day 13 to day 14 to the extent of only 72% of the increase observed in the unirradiated fetuses. Thus, expressed in terms of relative incorporation per whole fetus (g xc, see Tables 2 and 3), the differences were greater than the differences in relative incorporation per unit weight of fetal tissue. Table 4 presents data on the incorporation of '!C—Pheinto the A.LF, in fetal cell-free systems. Since precursor {C—Phe was main- t i