Hypothalamus Flashcards
(21 cards)
What is the autonomic function of the preoptic nucleus
Thermoregulation
What divides the hypothalamus into medial and lateral groups?
Fornix
What are the afferents from in the preoptic nucleus
Skin, mucous membranes and other hypothalamic nuclei
What are the efferent pathways from preoptic area?
Thirst, drinking sweating and panting
What are the. Euroendocrine effects of the preoptic nuclei
Control of gonadotrophin releasing hormone via arcuate nucleus
What nuclei are in the medial zone of the hypothalamus
Supraoptic, paraventricukar suprachiasmic, anterior nuc
What nuclei are in the tuberal region of the hypothalamus
Ventromedial nuc, dorsomedial nuc, infundibular/arcuate nuc
What nuclei are present in the medial zone of the hypothalamus?
Mammillary nucleus, posterior nucleus
What nuclei are pressent in the lateral zone of the hypothalamus?
Supraoptic lateral nuc lateral tuberal nuc perifornical area
Role of the supraoptic nuc
Release vasopressin and oxy
Role of paraventricular nuc
Release oxytocin and adh
Role of suprachiasmatic nuce
Retinal afferents, circadian cycle
Role of anterior nuc
Stria terminalis has parasympathetic effects
Role of ventromedial nuc
Hunger, thirst, appetite
Role of dorsomedial nuc
Hunger, thirst appetite
Infundibular/arcuate nucleus
Infundibulum release dopamine suppressing prolactin
Location and role of orexin neurones in the lateral hypothalamus
- Widespread in lateral hypothalamus and perifornical area
- Project widely through cns
- Important in sleep/wake cycles and feeding
- Stimulates appetite and food intake
- Promotes sexual activity
- Have leptin receptors (stimulation of these decrease appetite)
Tole of median forebrain bundle
Loosely arranged bundle of fibres extending from the anterior commissure to the midbrain running lateral to hypothalamus
Interconnects hypothal nuclei
Stimulation of mfb results in pleasure, reward centre in the nuc accumbens
Descending efferent connections to the hypothalamus
-Periventricular fibres to dorsal longitudunal fasciculus and then to autonomic preganglionic neurones of the brainstem and spinal cord
Also via midbrain raphe to sve motor neurones
Also to rf for lmns
- mamillotegmental tract to midbrain
- via mfb to midbrain
- neuroendocrine. Releasing factors amd hypothalmo-hypophysial tract
Ascending efferents of hypothal
To septal areas and olfactory cortex via mfb
Via mammilothalamic tract to anterior thalamic nuc limbic system
To dorsomedian thalamic nuc and prefrontal cortex
Afferents to hypothalamus
Olfaction Sexual olfaction Visceral sense from nuc trac sol Somatic sensation Limbic Pfc moods ect Retina
