Pituitary Function and Failure Flashcards
The hypothalamic-hypophyseal portal system connects
hypothalamus to the anterior pituitary
Neurohypophyisis
posterior pituitary (neural origin)
Adenohypophysis
anterior pituitary (glandular epithelial ectodermal origin)
Hormones of the posterior pituitary
ADH & oxytocin
Production of posterior pituitary hormones occurs in which nuclei?
Supraoptic and paraventricular nuclei of hypothalamus
Production of anterior pituitary hormones occurs in which nuclei?
Arcuate and other nuclei of hypothalamus
Posterior pituitary hormones are synthesized in
cell body of hypothalamic (supraoptic and paraventricular) neurons
How are posterior pituitary hormones released?
Packaged in vesicles from hypothalamus, stored in and released from posterior pituitary into blood
How are anterior pituitary hormones released?
Produced in arcuate and other nuclei of hypothalamus, released into capillaries of the hypothalamic-hypophyseal portal system; released from anterior pituitary into general circulation
What are the requirements for growth?
GH, genetics, adequate diet, lack of chronic disease and stress, normal mix of growth-influencing hormones (thyroid, insulin sex)
Fetal growth is determined by
genetics, environmental exposure (mother), nutrition, nutrition and health of mother
What are the effects of growth hormone?
increases fatty acids and glucose (anti-insulin effect) during prolonged fasting or exceeding of energy needs; hyperplasia and hypertrophy of soft tissues & skeleton; increased protein synthesis; increased IGFs from liver
Tissue and bone growth requires
GH & IGFs (protein and cell division), thyroid hormones, insulin (tissue growth), estrogen (close epiphyseal plates), calcium (bone growth)
When are thyroid hormones important to growth?
From gestation to adolescence where androgens and estrogens become more important
Growth hormone is important to growth from
birth to late teens/early 20s
