HYPOTHALAMUS

HYPOTHALAMUS
- situation
  - below thalamus
- boundaries or relations
  - anteriorly
    - lamina terminalis
  - posteriorly
    - subthalamus
  - inferiorly
    - structures in floor of third ventricle
  - superiorly
    - thalamus
  - laterally
    - internal capsule
  - medially
    - cavity of third ventricle
- extent
  - divided in to two lateral halves by
    - third ventricle
  - Zones
    - from the point of reference i.e., anterior column of fornix
      - medial zone
        
        thin subependymal or periventricular zone
        
        thicker intermediate zone
      - lateral zone
  - Anteroposterior regions
    - preoptic region
      - preoptic nucleus
        
        regulates release of gonadotropic hormones
    - supraoptic region
      - functionally
        
        supraoptic nucleus
        
        paraventricular nucleus
        
        both
        
        produce antidiuretic hormone
        
        regulate water balance
        
        connections with neurohypophysis
        
        fibers arising from this nuclei
        
        through hypothalamo-hypophyseal tract
        
        project in to posterior lobe of pitutary gland
        
        synthesize hormones
        
        vasopressin and oxytocin
        
        transported through axons
        
        terminating on the capillaries in neurohypophysis
        
        hormones are transported
      - anterior nucleus
        
        regulates body temperature by dissipation of heat
        
        stimulates parasympathetic nervous system
    - tuberal region
      - arcuate or infundibular nucleus
        
        produces hypothalamic releasing factors
        
        types
        
        releasing hormones
        
        ACTH
        
        FSH
        
        LH
        
        TSH
        
        GH
        
        release inhibiting hormones
        
        MSH
        
        LTH ( Luteotropic hormone)
        
        transported though
        
        tubero-infundibular tract
        
        to median eminence
        
        from here they go through
        
        hypothalamo hypophyseal portal system
        
        to secretory cells of anterior lobe
      - ventromedial nucleus
        
        satiety centre
        
        stimulation inhibits the urge to eat
      - dorsomedial nucleus
        
        stimulation
        
        causes obesity
        
        savage behaviour
    - mamillary region
      - posterior nucleus
        
        regulates body temperature by conservation of heat
        
        stimulate sympathetic nervous system
      - mamillary nuclei
        
        receives input from hippocompal formation through fornix
    - lateral nucleus
      - stimulation induces eating
- Master / Controller of
  - autonomic nervous system
  - endocrine system
    - sexual behaviour
  - Limbic system
    - emotional expression
    - biological clock
      - cyclical activities of body
        
        circadian rhythm
        
        sleeping - waking cycle
        
        body functions rhythm
  - together
    - helps to maintain homeostasis
- connections
  - afferent
    - fornix
    - stria terminalis
    - medial forebrain bundle
    - direct physical and chemical receptors
    - thalamohypothalamic
    - pallidohypothalamic
    - subthalamohypothalamic
  - Efferent
    - mamillothalamic tract
    - mamillotegmental tract

911	Hypothalamus	Hypothalamus
912	Area hypothalamica rostralis	Anterior hypothalamic area; anterior hypothalamic region
913	Nucleus anterior hypothalami	Anterior hypothalamic nucleus
914	Nucleus periventricularis ventralis	Anterior periventricular nucleus
915	Nuclei interstitiales hypothalami anterioris	Interstitial nuclei of anterior hypothalamus
916	Nucleus preopticus lateralis	Lateral preoptic nucleus
917	Nucleus preoptic medialis	Medial preoptic nucleus
918	Nucleus preopticus medianus	Median preoptic nucleus
919	Nucleus paraventricularis hypothalami	Paraventricular nucleus
920	Nucleus preopticus periventricularis	Periventricular preoptic nucleus
921	Nucleus suprachiasmaticus	Suprachiasmatic nucleus
922	Nucleus supraopticus	Supra-optic nucleus
923	Pars dorsolateralis	Dorsolateral part
924	Pars dorsomedialis	Dorsomedial part
925	Pars ventromedialis	Ventromedial part
926	Area hypothalamica dorsalis	Dorsal hypothalamic area; dorsal hypothalamic region
927	Nucleus dorsomedialis	Dorsomedial nucleus
928	Nucleus endopeduncularis	Endopeduncular nucleus
929	Nucleus ansae lenticularis	Nucleus of ansa lenticularis
930	Area hypothalamica intermedia	Intermediate hypothalamic area; intermediate hypothalamic region
931	Nucleus dorsalis hypothalami	Dorsal nucleus
932	Nucleus dorsomedialis	Dorsomedial nucleus
933	Nucleus arcuatus; nucleus semilunaris; nucleus infundibularis	Arcuate nucleus; infundibular nucleus
934	Nucleus periventricularis	Periventricular nucleus
935	Nucleus periventricularis posterior	Posterior periventricular nucleus
936	Area retrochiasmatica	Retrochiasmatic area; retrochiasmatic region
937	Nuclei tuberales laterales	Lateral tuberal nuclei
938	Nucleus ventromedialis hypothalami	Ventromedial nucleus of hypothalamus
939	Area hypothalamica lateralis	Lateral hypothalamic area
940	Area preoptica	Preoptic area
941	Nuclei tuberales laterales	Lateral tuberal nuclei
942	Nucleus perifornicalis	Perifornical nucleus
943	Nucleus tuberomammillaris	Tuberomammillary nucleus
944	Area hypothalamica posterior	Posterior hypothalamic area; posterior hypothalamic region
945	Nucleus premammillaris dorsalis	Dorsal premammillary nucleus
946	Nucleus mammillaris lateralis	Lateral nucleus of mammillary body
947	Nucleus mammillaris medialis	Medial nucleus of mammillary body
948	Nucleus supramammillaris	Supramammillary nucleus
949	Nucleus premammillaris ventralis	Ventral premammillary nucleus
950	Nucleus posterior hypothalami	Posterior nucleus of hypothalamus
951	Organum vasculosum laminae terminalis	Vascular organ of lamina terminalis
952	Zonae hypothalamicae	Zones of hypothalamus
953	Zona periventricularis	Periventricular zone
954	Zona medialis	Medial zone
955	Zona lateralis	Lateral zone
956	Neurohypophysis	Neurohypophysis
957	Substantia alba hypothalami	White substance of hypothalamus
958	Fasciculus longitudinalis posterior; fasciculus longitudinalis dorsalis Schütz	Posterior longitudinal fasciculus; dorsal longitudinal fasciculus Schütz
959	Commissura supraoptica dorsalis Ganser-Meynert	Dorsal supra-optic commissure Ganser-Meynert
960	Fibrae striae terminalis	Fibres of stria terminalis
961	Fornix	Fornix
962	Tractus hypothalamohypophysialis	Hypothalamohypophysial tract
963	Fibrae paraventriculohypophysiales	Paraventricular fibres
964	Fibrae supraopticohypophysiales	Supra-optic fibres
965	Fasciculus mammillotegmentalis Gudden	Mammillotegmental fasciculus Gudden
966	Fasciculus mammillothalamicus	Mammillothalamic fasciculus
967	Fasciculus medialis telencephali	Medial forebrain bundle
968	Tractus paraventriculohypophysialis	Paraventriculohypophysial tract
969	Fibrae periventriculares	Periventricular fibres
970	Tractus supraopticohypophysialis	Supra-opticohypophysial tract
971	Commissura supraoptica ventralis Gudden	Ventral supra-optic commissure Gudden
972	Tractus retinohypothalamicus	Retinohypothalamic tract