BIOM2071 Lecture Notes - Lecture 8: Hypophyseal Portal System, Pituitary Gland, Sella Turcica
Document Summary
Anatomy: hypothalamus within diencephalon, pituitary within hypophyseal fossa of sella turcica, hypothalamic stalk/infundibulum: connects hypothalamus to posterior pituitary, hypophyseal portal system: connects hypothalamus to anterior pituitary. Important for mother-baby and sexual partner bonding, and sexual arousal: can counteract effects of postnatal depression. Antidiuretic hormone (adh: peptide, release stimulators: osmolarity, pain, low blood pressure and drugs, cause vasoconstriction in high concentrations (called vasopressin, hypothalamus contains osmoreceptors high osmolarity = secretion of adh from. Inhibitors: alcohol and diuretics posterior pituitary (targets kidney tubules to reabsorb more water: causes oedema in pregnancy, low adh = diabetes insipidus (produce 20l urine/day excessive thirst) Anterior pituitary and hypothalamic input: hypothalamus: produces tropic hormones (regulate secretion of other hormones from anterior pituitary) Hypersecretion: primary hypersecretion: too much hormone secreted due to abnormality within gland, cause: immunology or tumours that ignore normal regulatory input and continuously secrete excess hormone, secondary hypersecretion: excessive stimulation from outside of gland.
