The hypothalamus forms what?
Floor for the 4th ventricle & portions of the 3rd ventricles lateral walls
What else is considered apart of the structure of the hypothalamus?
Infundibular stalk, and the optic chiasma
What are the 2 zones of the hypothalamus?
Medial & lateral zones
The medial zone can be subdivided into?
Anterior, intermediate & posterior areas
Has vague control of?
hunger, thirst, & sex
Hypothalamus controls ________ aspects of _______ expression
Physical, emotional
Hypothalamus has control over _______ functions
Visceral (autonomic)
Anterior & intermediate areas
Increases digestive motility
Decreases heart rate
Constriction of the pupil
Parasympathetic control
Posterior area (includes the post. nuclei & the mammillary bodies)
Increases heart rate & vasoconstriction
Decreases digestive motility
Responsible for pupil dilation, piloerection & sweat gland secretions
Sympathetic control
- Directly via neuron axon extensions into the posterior pituitary
- Indirectly via neurohormones to control the release of anterior pituitary hormones
Endocrine control from the hypothalamus
Area just above the optic chiasma
Anterior area
Nuclei found in the anterior area: (of the medial zone of the hypothalamus)
Supraoptic & paraventricular nuclei
Suprachiasmatic Nuclei (SCN)
Anterior nucleus
Preoptic area (nucleus)
This nuclei terminates in the posterior pituitary where they both release _______ and ADH hormones
Supraoptic & paraventricular nuclei
Oxytocin
Stimulates uterine contraction & the let down of breast milk
Oxytocin
Prevention of urination or help to retain H2O
ADH
Nucleus responsible for much of our circadial (daily) rhythms like temp, sleep, light, feeding…
Suprachiamatic Nuclei (SCN)
Suprachiamtic Nuclei is complexly connected to the ______ gland & it secretions into the bloodstream
Pineal gland
Gnerally known for parasympathetic functions
Anterior nucleus
Thermo-regulator; Esp. as the body HEATS up
Preoptic area (nucleus)
Nuclei found in the Intermediate area of the medial zone of the hypothalamus?
Dorsomedial nuclei
Ventromedial nuclei
Arcuate nuclei
Tuber cinereum
Significant GI tract parasympathetic influence, The nucleus is fairly diffuse
Dorsomedial nuclei
Very complex & many attributes. A center for eating & thirst gratification or fullness center
Ventromedial Nuclei
- Near the infundibular stalk
- Contribute axons to the so-called tract tuberoinfundibular tract
- Terminate & secrete their neurohormones into the perivascular spaces of the infundibular stalk
Arcuate nuclei
Neurohormones (of the arcuate nuclei) pass to the anterior pituitary by way of the bloodstream where they influence the release of pituitary hormones. Commonly know as:
Releasing factors
A term used to describe the undulating bulge between the infundibular stalk & the large mammillary bodies.
Tuber cinereum
Posterior area include what nuclei?
Mammillary bodies
Posterior nuclei
Nucleus (with hippocampal formation & anterior thalamic nuclei) important in short term memory
Mammillary bodies
Korsakov’s Syndrome
Loss of short term memory (from alcohol)
Thermoregulator: esp. as the body cools down. Stimulating shivering
Posterior nuclei
______ area is known for diverse sympathetic actions.
Posterior area
Pars nervosa and neurohypophsysis are another name for?
Posterior pituitary
The posterior pituitary develops from what embryologically?
Diencephalon
What is another name for the posterior pituitary ?
Pars nervousa or neurohypophysis
Which area gives rise to the anterior pituitary (adenohypophysis) and intermediate pituitary?
Rathke’s pouch
What would fibers from the hypothalamic nuclei be doing if they descends to specific nuclei for cranial nerve III, VII, IX or X?
Parasympathic
Most blood to the pituitary & infundibular stalk comes from branches of the?
Internal carotid arteries
Within the infundibular stalk the small arteries break into highly permeable capillaries called?
Fenestrated sinusoids
The fenestrated sinusoids pick up ______ _____ from the ________________ tract fibers.
Releasing factors ; tuberoinfundibular tract fibers
A series of small veins drain the hormone - laden blood b/t 2 capillary beds are called ?
Hypophyseal portal vein
Once the releasing factors enter the substance of the anterior pituitary they exert a controlling influence on the release of the ?
Pituitary hormones