title: Developmental and hormonal regulation of thermosensitive neuron potential activity in rat brain.
abstract: To understand the involvement of thyroid hormone on the postnatal development of hypothalamic thermosensitive neurons, we focused on the analysis of thermosensitive neuronal activity in the preoptic and anterior hypothalamic (PO/AH) regions of developing rats with and without hypothyroidism. In euthyroid rats, the distribution of thermosensitive neurons in PO/AH showed that in 3-week-old rats (46 neurons tested), 19.5% were warm-sensitive and 80.5% were nonsensitive. In 5- to 12-week-old euthyroid rats (122 neurons), 33.6% were warm-sensitive and 66.4% were nonsensitive. In 5- to 12-week-old hypothyroid rats (108 neurons), however, 18.5% were warm-sensitive and 81.5% were nonsensitive. Temperature thresholds of warm-sensitive neurons were lower in 12-week-old euthyroid rats (36.4+/-0.2 degrees C, n = 15, p<0.01,) than in 3-week-old and in 5-week-old euthyroid rats (38.5+/-0.5 degrees C, n = 9 and 38.0+/-0.3 degrees C, n = 15, respectively). The temperature thresholds of warm-sensitive neurons in 12-week-old hypothyroid rats (39.5+/-0.3 degrees C, n = 8) were similar to that of warm-sensitive neurons of 3-week-old raats (euthyroid and hypothyroid). In contrast, there was no difference in the thresholds of warm-sensitive neurons between hypothyroid and euthyroid rats at the age of 3-5 weeks. In conclusion, monitoring the thermosensitive neuronal tissue activity demonstrated the evidence that thyroid hormone regulates the maturation of warm-sensitive hypothalamic neurons in developing rat brain by electrophysiological analysis.
authors.affiliation: Nagasaki University School of Medicine, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Belugin
authors.forename: K
authors.initials: K
authors.lastname: Akino
authors.forename: N
authors.initials: N
authors.lastname: Takamura
authors.forename: M
authors.initials: M
authors.lastname: Mine
authors.forename: D
authors.initials: D
authors.lastname: Romanovsky
authors.forename: V
authors.initials: V
authors.lastname: Fedoseev
authors.forename: A
authors.initials: A
authors.lastname: Kubarko
authors.forename: M
authors.initials: M
authors.lastname: Kosaka
authors.forename: S
authors.initials: S
authors.lastname: Yamashita
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D007031:Hypothalamus / Q000166:cytology / Q000254:growth & development* / Q000502:physiology*; D007032:Hypothalamus, Anterior / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D007037:Hypothyroidism / Q000503:physiopathology; D008297:Male; D009475:Neurons, Afferent / Q000502:physiology*; D011301:Preoptic Area / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013823:Thermoreceptors / Q000502:physiology*; D013963:Thyroid Hormones / Q000502:physiology*
chemical_list: D013963:Thyroid Hormones