PROTECTION OF THE EMBRYO AGAINST THE CONGENITAL AND LETHAL EFFECTS OF X- IRRADIATION. PART I
The effects of 15 agents, some given before and some after x irradiation to 200 r, have been studied for their effectiveness in protecting the 8.5-day mouse embryo against embryonic or fetal death and the development of the severe cephalic congenital anomaly known as exencephalia (or brain hernia). Some 4979 fetuses were examined. Of the agents studied, only cysteinamine, cystamine, and anoxia proved to be statistically "protective" at all. Cysteinamine and cystamine (both -SH compounds) given I.P. before x irradiation to 200 r allowed 73 to 80% of the 8.5-day embryos to survive to term while the untreated but irradiated control litters had a survival of only 41%. Funther, there was considerable reduction in bcth uterine death and the congenital anomaly of exencephalia. Anoxia (6% O/sub 2/ + 94% N/sub 2/) aIlowed 71% to come through as ""apparently normal," an increase of 30% over the unprotected irradiated controls. Whether there is long-term damage to the 8.5day embryo from the temporary anoxia alone has not been determined, although the anoxic controls showed 96% " apparently nornnal." Distilled water given I.P. before irradiation, making the milieu of the embryos hypotonic, appeared to be deleterious, causing 2% exencephalia even without x irradiation. When combined with x rays, distilled water reduced the "apparentiy normals" to 31%, or 10% lower than with irradiation alone. Saline in various concentrations was not protective. None of the tissue homogenates (spleen, marrow, liver, or brain of a homologous newborn source) proved to be of any protective value. It is suggested that the protective element in such tissue homogenates may be cellular since the placenta acts as the most efficient filter to allow only the dialyzable substances through to the embryo. However, the fact that the 8.5-day mouse embryo has not yet developed its hematopoietic syatem may explain the failure of homogenates which seem to protect through hematopoietic regeneration. Hypoxia from hypoglycemia following insulin injection was not protective. Insulin or dextrose or the two in combination were -not panticularly harraful to the 8.5-day mouse embryo but when combined with x irradiation were very damaging. "Protection" as used in this study is statistical and relates to the percentage changes in ""apparently normal" fetuses, resorptions, deaths, and congenital anomalies. It does not imply that the surviving mice are without irradiation sequelae. In fact many of the "apparently normals" have eye defects and this might well reveal other and more subtle C. N. 8. damage. On the basis of survival, however, cysteinamine, cystamine, and anoxia did afford some protection. (auth)
- Research Organization:
- Columbia Univ., New York
- NSA Number:
- NSA-14-022762
- OSTI ID:
- 4154128
- Journal Information:
- Atompraxis (West Germany) Incorporated in Kerntechnik, Vol. Vol: 6; Other Information: Orig. Receipt Date: 31-DEC-60
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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AGE
AMINES
ANIMAL CELLS
BLOOD
BLOOD FORMATION
BONE MARROW
BRAIN
CYSTAMINE
CYSTEINE
DIALYSIS
DIFFUSION
DRUGS
EFFICIENCY
EMBRYOS
EYES
FETUSES
FILTERS
GLUCOSE-D
HORMONES
IMMUNITY
INSULIN
INTESTINE
INTRAPERITONEAL
IRRADIATION
ISOMERS
LETHAL DOSE
LIVER
MALFORMATIONS
MEMBRANES
METABOLISM
MICE
NERVOUS SYSTEM
NITROGEN
NUMERICALS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
OXYGEN
PLACENTA
PREGNANCY
RADIATION DOSES
RADIATION INJURIES
RADIATION PROTECTION
REPRODUCTION
SALTS
SEPARATION PROCESSES
SOLUTIONS
SPLEEN
STANDARDS
STATISTICS
SUGARS
SURVIVAL TIME
SUSPENSIONS
TESTING
TISSUES
V