title: Manipulating thyroid status alters endoplasmic reticulum calcium homeostasis in rat cerebellum.
abstract: Thyroid-related hormones regulate the efficiency and expression of sarco-endoplasmic reticulum calcium ATPases in cardiac and skeletal muscle. However, little is known about the relationship between thyroid hormones and calcium (Ca2+) homeostasis in the brain. It is hypothesized that manipulating rat thyroid hormone levels would induce significant brain Ca2+ adaptations consistent with clinical findings. Adult male Sprague-Dawley rats were assigned to one of three treatment groups for 28 days: control, hypothyroid (6-n-propyl-2-thiouracil (PTU), an inhibitor of thyroxine (T4) synthesis), and hyperthyroid (T4). Throughout, rats were given weekly behavioral tests. Ca2+ accumulation decreased in the cerebellum in both hyper- and hypothyroid animals. This was specific to different ER pools of calcium with regional heterogeneity in the response to thyroid hormone manipulation. Behavioral tasks demonstrated sensitivity to thyroid manipulation, and corresponded to alterations in calcium homeostasis. Ca2+ accumulation heterogeneity in chronic hyper- and hypothyroid animals potentially explains clinical manifestations of altered thyroid status.
authors.affiliation: Department of Neurology, Uniformed Services University of the Health Sciences, B-3012, 4301 Jones Bridge Road, Bethesda, MD 20814, USA. jeffrey.cole@usuhs.mil
authors.forename: J T
authors.initials: JT
authors.lastname: Cole
authors.forename: D C
authors.initials: DC
authors.lastname: McMullen
authors.forename: W S
authors.initials: WS
authors.lastname: Kean
authors.forename: A M
authors.initials: AM
authors.lastname: Yarnell
authors.forename: J J
authors.initials: JJ
authors.lastname: Lucky
authors.forename: M A
authors.initials: MA
authors.lastname: Selak
authors.forename: J E
authors.initials: JE
authors.lastname: Buonora
authors.forename: N E
authors.initials: NE
authors.lastname: Grunberg
authors.forename: A
authors.initials: A
authors.lastname: Verma
authors.forename: W D
authors.initials: WD
authors.lastname: Watson
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D015153:Blotting, Western; D001921:Brain / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002531:Cerebellum / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism*; D006706:Homeostasis; D006980:Hyperthyroidism / Q000139:chemically induced / Q000378:metabolism; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008861:Microsomes / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013962:Thyroid (USP) / Q000494:pharmacology*; D013963:Thyroid Hormones / Q000494:pharmacology*; D013974:Thyroxine / Q000633:toxicity; D014284:Triiodothyronine / Q000494:pharmacology
chemical_list: D013962:Thyroid (USP); D013963:Thyroid Hormones; D014284:Triiodothyronine; D013974:Thyroxine; D002118:Calcium