1993 Fiscal Year Final Research Report Summary
Studies on Placental Transfer and Milk Secretion of Zn-65 and Mn-54 in Experimental Animals
| Project/Area Number |
04660316
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
基礎獣医学
|
|---|
| Research Institution | IWATE UNIVERSITY |
|---|
Principal Investigator |
MATSUSAKA Naonori Iwate University Faculty of Agriculture Professor, 農学部, 教授 (70003754)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SATO Itaru Iwate University Faculty of Agriculture Assistant, 農学部, 助手 (60225919)
NISHIMURA Yoshikazu National Institute of Radiological Sciences Senior Scientist, 環境衛生研究部, 主任研究官 (20164600)
SHIGA Akio Iwate University Faculty of Agriculture Assoc.Professor, 農学部, 助教授 (20003783)
KOBAYASHI Haruo Iwate University Faculty of Agriculture Professor, 農学部, 教授 (60003779)
SHINAGAWA Kunihiro Iwate University Faculty of Agriculture Assoc.Professor, 農学部, 助教授 (60133906)
|
|---|
| Project Period (FY) |
1992 – 1993
|
| Keywords | experimental animals / radioactive zinc / radioactive manganese / placental / milk / Zn-65 / Mn-54 |
|---|
| Research Abstract |
The fetal uptake of radioactive zinc (Zn-65) and manganese (Mn-54) was studied as a function of gestational age in mice. The fetal uptake of both nuclides increased markedly with time after administration to the pregnant mice of gestation Day 17, i.e., from 3% of the dose 30 min after administration to 36% of the dose 24 hr after administration as a litter. The similar increasing tendency of the fetal uptake of Mn-54 was observed in mice of the same gestatonal age, i.e., from 3% of the dose 30 min after administration to 9% of the dose 24 hr after administration as a litter. The fetal uptake of Zn-65 24 hr after administration was 4 times greater than that of Mn-54.
These two nuclides were given simultaneously with a single subcutaneous dose to the pregnant mice of gestation Day 0, 7 and 14 as a double tracer, and the radioactivity in newborns just after birth was measured by a pulse-height analyzer. The amounts of Zu-65 transferred to fetuses in utero in the pregnant mice of gestation Day 0, 7 and 14 were 11%, 12% and 28% of the dose as a litter, respectively. Therefore, the amount of Zu-65 in the newborns became gerater when the gestation period advanced to tern. Similar results were obtained concerning Mn-54.
The amount of Zn-65 and MN-54 secreted into milk was estimated from the pup's body burden during nursing period, using foster-dam method. It was demonstrated that the secretion of both nuclides into milk is an imnportant pathway of elimination.
|
Research Products
(10 results)
