Mice lacking the thyrotropin-releasing hormone gene: what do they tell us?
Thyrotropin-releasing hormone (TRH) is localized in the brain hypothalamus and stimulates the secretion and synthesis of pituitary thyrotropin (TSH). Although TRH deficiency caused by artificial hypothalamic destructions has been reported to result in significant decreases in TSH secretion in rodents, clinical observations from the patients with possible TRH deficiency did not entirely agree with these animal results. Because of its ubiquitous distribution throughout the brain and in the peripheral tissues, TRH has been suggested to possess a wide variety of functions in these regions. However, the neurobehavioral and peripheral actions of TRH still remains to be established. It has been, therefore, anticipated that detailed analysis of TRH-knockout mice might provide insight into the physiological significance of endogenous TRH. The present review focuses on the phenotypic findings of mice deficient in TRH.
Yamada
Masanobu
M
Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi, Japan.
Satoh
Tetsurou
T
Mori
Masatomo
M
D000818:Animals; D001921:Brain / Q000378:metabolism; D003001:Cloning, Molecular; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D005314:Embryonic and Fetal Development; D020249:Hormone Replacement Therapy; D007037:Hypothyroidism / Q000188:drug therapy / Q000209:etiology; D051379:Mice; D018345:Mice, Knockout / Q000235:genetics*; D010456:Peptides, Cyclic / Q000096:biosynthesis; D010641:Phenotype; D010879:Piperazines; D010903:Pituitary Gland, Anterior / Q000196:embryology; D011498:Protein Precursors / Q000235:genetics; D013972:Thyrotropin / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism / Q000627:therapeutic use; D013974:Thyroxine / Q000627:therapeutic use
D010456:Peptides, Cyclic; D010879:Piperazines; D011498:Protein Precursors; C063596:prepro-thyrotropin-releasing hormone; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; C015924:histidyl-proline diketopiperazine; D013974:Thyroxine