Interaction of age and thyroid hormone status on beta-endorphin content in rat corpus striatum and hypothalamus.
These studies investigated the effect of aging on thyroid hormone regulation of beta-endorphin in rat corpus striatum and hypothalamus. In both brain areas, basal levels of beta-endorphin declined with age. In addition, age modified the response of beta-endorphin to thyroid hormone status. Hypothyroid rats aged 6 months (mature) exhibited a 67% mean decline in the level of beta-endorphin in the corpus striatum. Hypothyroid rats aged 20-24 months (senescent) exhibited no change in the level of beta-endorphin in the corpus striatum. Hypothyroid rats aged 6 months had a 28% mean decline in the level of hypothalamic beta-endorphin. There was no change in hypothalamic beta-endorphin content in hypothyroid senescent rats. Hyperthyroidism resulted in elevations of beta-endorphin in both the corpus striatum and hypothalamus in senescent, but not mature rats. Changes in beta-endorphin seen with age are at least in part thyroid hormone dependent. In addition, age is capable of modifying the response of brain tissue to thyroid hormone.
D000375:Aging; D000818:Animals; D003342:Corpus Striatum / Q000378:metabolism*; D004723:Endorphins / Q000378:metabolism*; D007031:Hypothalamus / Q000378:metabolism*; D008297:Male; D051381:Rats; D013961:Thyroid Gland / Q000502:physiology; D013963:Thyroid Hormones / Q000502:physiology*; D014284:Triiodothyronine / Q000097:blood
D004723:Endorphins; D013963:Thyroid Hormones; D014284:Triiodothyronine