Download tuber cinereum

Novi Anantari, dr
Anatomy Department-FK Unisba
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This region, located in the ventral diencephalons,
just under the thalamus (hypo-, “under”), forming
the floor and the ventral part of the walls of the
third ventricle.
The hypothalamus weighs about 4 grams .
It contains the highest integrative centers of the
ANS.
The shallow hypothalamic sulcus on the wall of
the third ventricle demarcates the hypothalamus
from the thalamus. Anteriorly, the hypothalamus
is limited by the lamina terminalis, medially by the
third ventricle, laterally by the subthalamus, and
posteriorly it is continous with the midbrain.
The hypothalamus includes :
 The optic chiasm is located in the rostral portion of the
hypothalamic floor.
 The tuber cinereum is the portion of the hypothalamic
floor between the optic chiasm and the mammillary
bodies; which is a funnel-shaped eminence
 The infundibulum, a collective term for the median
eminence and the infundibular stalk or stalk of
pituitary, extends ventrally from the tuber cinereum to
the pars nervosa of the hypofisis
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the infundibular recess : evaginate lumen of the
third ventricle.
The median eminence (the highly vascularized
floor of the hypothalamus) is a part of the tuber
cinereum
The mammillary bodies are paired spherical
nuclei (paired white masses) located inferior to
the gray matter of the hypothalamic floor,
caudal to the tuber cinereum and rostral to the
posterior perforated substance.
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The hypothalamus consists of 3 regions :
The supraoptic region
ostral; the suprachiasmatic nucleus, the supraoptic
nucleus, the paraventricular nucleus, the anterior
hypothalamic area, and the lateral hypothalamic area;
 The mammillary region, which is most caudal;
containing the following strucrures : the mammillary
nuclei and the posterior nucleus;
 The tuberal region; which contains the following
structures : the dorsomedial nucleus, the ventromedial
nucleus, the arcuate nucleus, and the lateral hypothalamic
area.
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 The
supraoptic region (rostral)
 the suprachiasmatic nucleus,
 the supraoptic nucleus,
 the paraventricular nucleus,
 the anterior hypothalamic area, and
 the lateral hypothalamic area
The preoptic area and hypothalamus regulate
endocrine activity through 2 mechanism :
 directly, by secretion of neuroendocrine
products into the general circulation through
the vasculature of the posterior pituitary
(neurohypofisis)
 indirectly, by secretion of releasing hormones
into the local portal plexus, which drains into
the blood vessels of the anterior pituitary
(adenohypofisis).
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The Master Gland :produces hormones that control the
activity of other endocrine glands
It is a small gland located in the sella turcica (Turk's
saddle) of the sphenoid bone of the skull, immediately
inferior to the hypothalamus of the brain.
The sphenoid bone serves as a protective cradle around
the gland.
A stalk or infundibulum attaches the gland to the
hypothalamus.
Hormones and regulatory molecules from the
hypothalamus travel down a plexus of blood vessels in
the infundibulum to reach the hypophysis.
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Contains two lobes, the anterior and posterior lobes.
The anterior lobe, the adenohypophysis or pars distalis,
produce many hormones that target other endocrine glands
The pars intermedia, separates the anterior and posterior
pituitary. It produces, melanocyte stimulating hormone
(MSH).
The posterior lobe, the neurohypophysis or pars nervosa,
does not produce hormones;
The hypothalamus produces antidiuretic hormone (ADH)
and oxytocin (OT) which pass down the infundibulum to
enter the neurohypophysis for storage and release.The
neurohypophysis consists of axons from hypothalamic
neurons.
The normal adult pituitary gland weighs between 0.4 and
0.8 gram.
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Cells in the supraoptic and paraventricular nuclei of
the hypothalamus produce the peptide hormones
oxytocin and vasopressin (antidiuretic hormone),
The peptide hormones are transported down the
hypothalamo-hypophyseal tract and secreted from axon
terminals directly into the systemic circulation in the
posterior pituitary (neurohypophysis).
Both hormones are produce initially as pro-hormones
in neurons of the hypothalamic nuclei.
Vasopressin stimulates water reabsorption by the
kidney, and oxytocin stimulates uterine contraction
and milk ejection.
Hypothalamic and
pituitary hormones
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Cells in the hypothalamus also control the anterior
pituitary.
Cells in a number of nuclei including the arcuate
nucleus and part of the ventromedial nucleus
produce peptide-releasing hormones
Peptide Releasing Hormones are transported to
their terminals and secreted into capillaries in the
median eminence and pituitary stalk.
These capillaries collect into very short portal veins
that deliver the releasing hormones to cells of the
anterior pituitary (adenohypophysis).
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Subpopulations of cells of the anterior pituitary
synthesize and secrete :
Thyroid-stimulating hormone,
Follicle-stimulating hormone,
Luteinizing hormone,
Growth hormone,
Adrenocorticotropic hormone,
Prolactin.
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The blood supply reaches the anterior pituitary
by a circuitous route through the
hypothalamus.
Two derivatives of the internal carotid arteries,
the superior hypophyseal arteries (SHA),
branch in the subarachnoid space around the
pituitary stalk and terminate in the capillary
network of the median eminence.
These capillaries have a fenestrated
endothelium which allows easy access to the
hypothalamic releasing hormones.
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Transport of substances from the capillaries to the
median eminence is also facilitated because the
median eminence lies outside the blood-brain
barrier.
The capillaries then coalesce to form 6 to 10
straight veins known as the hypothalamicpituitary portal circulation. These veins constitute
the main blood supply to the anterior lobe and
supply it with nutrients as well as information
from the hypothalamus. A direct arterial blood
supply the anterior lobe is also present.
The posterior pituitary is supplied entirely from
the inferior hypophyseal arteries.
Hormones of the hypothalamic anterior pituitary pathway
A complex
endocrine
pathway