The effects of hypothyroidism on 5-HT1A and 5-HT2A receptors and the serotonin transporter protein in the rat brain.
The effects of hypothyroidism on 5-HTIA and 5-HT2A receptors and the serotonin transporter protein were studied in thyroidectomized male Wistar rats in two experimental groups: 1) animals kept on an iodine-free diet hypothyroid rats) and 2) animals kept on thyroxine (15 microg/kg) for 21 days (giving normal thyroid hormone levels. euthyroid animals). Sham-operated rats served as controls. Binding of [3H]8-OH-DPAT with 5-HTIA receptors and [3H]citalopram with the transporter protein in the hippocampus and midbrain showed no changes in hypothyroid rats as compared with controls. Conversely. there were significant decreases in [3H]ketanserin binding to 5-HT2A receptors in the frontal cortex in hypothyroid rats as compared with controls; this decrease was reversed by thyroxine treatment. Thus, losses of cortical 5-HT2A receptors appears to be the main consequence of hypothyroidism at the level of the serotonin system of the brain.
Kulikov
A V
AV
Institute of Cytology and Genetics, Siberian Division, Russian Academy of Sciences, Novosibirsk.
Jeanningro
R
R
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000378:metabolism; D000818:Animals; D001923:Brain Chemistry / Q000502:physiology*; D002352:Carrier Proteins / Q000378:metabolism*; D015283:Citalopram / Q000378:metabolism; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D006624:Hippocampus / Q000378:metabolism / Q000502:physiology; D007037:Hypothyroidism / Q000378:metabolism*; D007202:Indicators and Reagents; D007650:Ketanserin / Q000378:metabolism; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D026901:Membrane Transport Proteins; D008636:Mesencephalon / Q000378:metabolism / Q000502:physiology; D009419:Nerve Tissue Proteins; D011869:Radioligand Assay; D051381:Rats; D017208:Rats, Wistar; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin / Q000502:physiology*; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists / Q000378:metabolism; D050486:Serotonin Plasma Membrane Transport Proteins; D013965:Thyroidectomy; D013974:Thyroxine / Q000097:blood
D002352:Carrier Proteins; D007202:Indicators and Reagents; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists; D050486:Serotonin Plasma Membrane Transport Proteins; C493232:Slc6a4 protein, rat; D015283:Citalopram; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D007650:Ketanserin; D013974:Thyroxine