Immobilization of collared peccaries (Tayassu tajacu) and feral hogs (Sus scrofa) with Telazol and xylazine

Quantitative [125I]protein G-based immunohistochemistry was used to map the distribution of beta1 thyroid hormone receptor (TRbeta1) in normal and thyroidectomized adult rat brain, using a previously characterized polyclonal antibody. The distribution of TRbeta1-like immunoreactivity in normal brain was largely but not perfectly concordant with previous accounts of TRbeta1 mRNA distribution in rat brain. Thyroidectomy resulted in increased immunolabeling in most brain regions (mean increase: 14%, range: -4% to +25%), with statistically significant effects being observed in 9 of the 36 brain regions examined. Brain regions showing the most pronounced effects included the habenular nucleus (+22%), the oriens layer of the hippocampal CA3 region (+24%), and the lateral geniculate nucleus of the thalamus (+23%). These results demonstrate that the TRbeta1 protein in brain is capable of plastic changes in response to adult-onset alterations in TH levels. The observed pattern of brain regional receptor changes following thyroidectomy may provide clues for functional effects of thyroid function alterations in adults.