In situ estradiol  and progestin (R5020) localization in the vascularly separated and isolated hypothalamus of the rhesus monkey.
A neurosurgical procedure has been developed for vascular isolation of the hypothalamus-thalamus region of the rhesus monkey brain. Utilizing this preparation, the left and right halves of the hypothalamus were perfused simultaneously, but separately, with a dextran-blood solution. Radiolabeled steroids were directly perfused in the dextran-blood into either the left or right half of the hypothalamus. Studies with radiolabeled gonadal steroids indicate that the majority of the carotid circulation is confined to the hypothalamus-thalamus area in this brain preparation and the cross-circulation of labelled steroids between the left and right sides of the hypothalamus is less than 10%. The usefulness of the preparation is illustrated by an autoradiographic study of the in situ hypothalamic distribution of (3H)estradiol in ovariectomized rhesus monkeys and of the synthetic progestin(3H)R5020 in estrogen-primed, ovariectomized rhesus monkeys. The direct perfusion of the (3H) steroids into the hypothalamus greatly increases the sensitivity of such compared to systemic administration of the (3H) steroids. The perfusion of one-half of the hypothalamus with )3H) steroid and the other half with (3H) steroids. The perfusion of one-half of the hypothalamus with (3H) steroid and the other half with (3H) steroids. The perfusion of one-half of the hypothalamus with (3H) steroid and the other half with (3H)steroid plus radioinert steroids permits in 1 animal, acting as its own control, the examination of a saturable distribution of a gonadal steroid in the rhesus monkey hypothalamus.
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D007031:Hypothalamus / Q000378:metabolism*; D008253:Macaca mulatta; D009649:Norpregnadienes / Q000378:metabolism*; D011397:Promegestone / Q000378:metabolism*
D009649:Norpregnadienes; D004958:Estradiol; D011397:Promegestone