3.13.14 29 Hypothalamus Flashcards
(26 cards)
What connects to the limbic system and plays a major role in elaborating our MOST BASIC DESIRES for survival via efferent outflow to somatic and autonomic centers?
Hypothalamus
What mnemonic summarizes all of the functions of the hypothalamus
Hypothalamus wears “TAN HATS to bed”
Thirst/water balance Adenohypophysis Neurohypophysis --- Hunger Autonomics Temperature Sexual urges --- To bed = circadian rhythm
What nuclei regulate temperature?
Posterior = heating = sympathetic (constriction of peripheral blood vessels, shivering; decreased sweating)
What are the key AFFERENT pathways of the hypothalamus?
Dorsal longitudinal fasciculus
Stria terminalis
Fornix
Retina
What are the key EFFERENT pathways of the hypothalamus?
Dorsal longitudinal fasciculus
Stria terminalis
Mammillothalamic tract
Hypophyseal portal system
What connects the hypothalamus to and from the brainstem/spinal cord?
Dorsal longitudinal fasciculus
What connects the amygdaloid complex to and from the hypothalamus?
Stria terminalis
What connects the Hippocampal formation and septum to the hypothalamus? (Afferent only)
Fornix
What connects the hypothalamus to the cortex and mammillary bodies?
Mammillothalamic tract
How does the hypothalamus regulate the anterior pituitary?
Releasing and inhibitory hormones through the hypophyseal portal system
Describe the symptoms and affected structures of amenorrhea
Arrest of menses Insufficient LHRH or FSH -- AH/POA Tuberal hypothalamus Pituitary
Describe the symptoms and affected structures of galactorrhea
Excessive milk production Prolactin and oxytocin -- Arcuate nucleus AH/POA Median eminence Pituitary stalk
Describe the symptoms and affected structures of poikilothermia
Disregulation of temperature -- PH (primarily) or PH and AH/POA
Describe the symptoms and affected structures of diabetes insipidus
Polydipsia (thirst) and polyuria -- Supraoptic nucleus Paraventricular nucleus Pituitary stalk
Describe the association of hypothalamus pathology and visual signs
Tumors of the pituitary can compress the optic nerve and/or optic chiasm (usually bitemporal heminanopia)
Describe the symptoms and affected structures of acromegaly
Adenohypophyseal lesions (ant. pituitary)
Arcuate nucleus
Periventricular region of hypothalamus
Describe the symptoms and affected structures of Cushing’s disease
Hyperadrenocorticism (increased ACTH); usually pituitary adenoma -- Hypertension Weight gain (skin changes, striae); truncal obesity and buffalo hump Moon facies Hyperglycemia Osteoporosis Amenorrhea Immune suppression Muscle weakness
Where to the autonomic projections of the hypothalamus end up?
Parasympathetics:
Brainstem (EW, S/I salivatory, dorsal motor)
Spinal cord (Parasympathetic nuclei - S2-4)
—
Sympathetics:
Spinal cord (IML - T1-L2)
What nucleus is associated with temperature?
(Same as autonomics)
Cooling = anterior/preoptic area
Heating = posterior
What nucleus is associated with adenohypophysis control?
Arcuate and paraventricular
What nucleus is associated with neurohypophysis control?
Supraoptic and paraventricular
What nucleus is associated with hunger/satiety?
Hunger = lateral Satiety = ventromedial
What nucleus is associated with autonomics?
(Same as temp control)
Parasympathetic = anterior/preoptic (cooling)
Sympathetic = posterior (heating)
What nucleus is associated with thirst?
(Same as neurohypophysis control)
Supraoptic and paraventricular
