Restoration of brain growth in fetal sheep after iodized oil administration to pregnant iodine-deficient ewes

doi:10.1016/0022-510X(84)90137-0

Journal of the Neurological Sciences

Volume 66, Issue 1, October 1984, Pages 15-26

https://doi.org/10.1016/0022-510X(84)90137-0 Get rights and content

Abstract

Iodized oil was administered as a single intramuscular injection to pregnant iodine-deficient ewes at 100 days gestation and the subsequent growth of their fetuses compared with that of fetuses of severely iodine-deficient ewes and of iodine-replete ewes, all of which were fed the same low-iodine diet.

The administered iodine produced a remarkable improvement in thyroid function and physical appearance of the fetuses, accompanied by an increase in brain growth and to a lesser extent in body growth, which at 140 days was only slightly (but significantly) less than that of the controls. There was restoration of the number of cells (DNA) and myelination (cholesterol/DNA) in the cerebellum and cerebral hemispheres which suggests a catch-up of neuroblast development during pregnancy.

Histological examination, however, revealed that counts of synapses (density) in the cerebral cortex after iodized oil were still less than those of the control fetal brains.

The relevance of these findings to the effects of iodine deficiency on human brain development is discussed.

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Restoration of brain growth in fetal sheep after iodized oil administration to pregnant iodine-deficient ewes

Abstract

Anal. Biochem.

Lancet

Estimation of nuclear population from microtome sections

Anat. Rec.

The density of synapses and neurones in the motor and visual areas of the cerebral cortex

J. Anat. (Lond.)

The later development of the brain and its vulnerability

Thyroxine and triiodothyronine metabolism in maternal and fetal sheep

Pediat. Res.

Thyroid function, iodine nutrition and fetal brain development

Clin. Endocrinol.