title: Amelioration of improper differentiation of somatostatin-positive interneurons by triiodothyronine in a growth-retarded hypothyroid mouse strain.
abstract: Thyroid hormone (TH) plays an important role in brain development, and TH deficiency during pregnancy or early postnatal periods leads to neurological disorders such as cretinism. Hypothyroidism reduces the number of parvalbumin (PV)-positive interneurons in the neocortex and hippocampus. Here we used a mouse strain (growth-retarded; grt) that shows growth retardation and hypothyroidism to examine whether somatostatin (Sst)-positive interneurons that are generated from the same pool of neural progenitor cells as PV-positive cells are also altered by TH deficiency. The number of PV-positive interneurons was significantly decreased in the neocortex and hippocampus of grt mice as compared with normal control mice. In contrast to the decrease in the number of PV neurons, the number of Sst-positive interneurons in grt mice was increased in the stratum oriens of the hippocampus and the hilus of the dentate gyrus, although their number was unchanged in the neocortex. These changes were reversed by triiodothyronine administration from postnatal day (PD) 0 to 20. TH supplementation that was initiated after PD21 did not, however, affect the number of PV- or Sst-positive cells. These results suggest that during the first three postnatal weeks, TH may be critical for the generation of subpopulations of interneurons.
authors: Laboratory of Information Biology, Graduate School of Information Sciences, Tohoku University, Sendai, Japan. Electronic address: uchida@m.tohoku.ac.jp.
authors: Katsuya
authors: K
authors: Uchida
authors: Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
authors: Yusuke
authors: Y
authors: Taguchi
authors: Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
authors: Chika
authors: C
authors: Sato
authors: Department of Stomatology and Oral Surgery, Graduate School of Medicine, Gunma University, Maebashi, Japan.
authors: Hidetaka
authors: H
authors: Miyazaki
authors: Health Effects Research Group, National Institute of Occupational Safety and Health, Kawasaki, Japan.
authors: Kenichi
authors: K
authors: Kobayashi
authors: Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
authors: Tetsuya
authors: T
authors: Kobayashi
authors: Laboratory of Information Biology, Graduate School of Information Sciences, Tohoku University, Sendai, Japan.
authors: Keiichi
authors: K
authors: Itoi
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics*; D005260:Female; D005317:Fetal Growth Retardation / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism; D007037:Hypothyroidism / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism; D007395:Interneurons / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D011247:Pregnancy; D013004:Somatostatin / Q000096:biosynthesis*; D014284:Triiodothyronine / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D014284:Triiodothyronine; D013004:Somatostatin
keywords: Hippocampus; Hypothyroid; Neocortex; Parvalbumin; Somatostatin; Thyroid hormone