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a.  Circadian rhythm: Suprachiasmatic nuclei
b.  Temperature:
  1. Heat response: mediated by anterior hypothalamus
  2. Cold response: mediated by posterior hypothalamus
Lateral preoptic area

  1. Feeding center: lateral hypothalamus
  2. Satiety center: ventromedial hypothalamus
  3. Leptin  is a 16 kDa protein hormone that plays a key role in regulating energy intake and energy expenditure, including appetite and metabolism. Leptin is one of the most important adipose derived hormones. The Ob(Lep) gene is located on chromosome 7 in humans. Leptin binds to the ventromedial nucleus of the hypothalamus, known as the "appetite center." Leptin signals to the brain that the body has had enough to eat, or satiety. The circulating leptin levels give the brain input regarding energy storage so it can regulate appetite and metabolism. Leptin works by inhibiting the activity of neurons that contain neuropeptide Y (NPY) and agouti-related peptide (AgRP), and by increasing the activity of neurons expressing α-melanocyte-stimulating hormone (α-MSH).Leptin resistance can lead to Obesity in which incresed Leptin levels are present. Leptin receptors: especially in arcuate nuclei and paraventricular nuclei
Principal Polypeptides and Proteins That May Be Involved in Regulation the Appetite for Food.
Increase food intake (orexigenic) Decrease food intake (antiorexigenic)
AGRP Bombesin
β-Endorphin CART
Galanin CCK
Ghrelin CRH
MCH Glucagon
Neuropeptide Y GLP-1, 2
Orexin A GRP
Orexin B Leptin
  Peptide YY
  1. Sexual behavior : Anterior ventral hypothalamus, piriform cortex (in male)
  2. Catecholamines: dorsal and posterior hypothalamus
Control of pituitary hormones

a.  Anterior
  1. CRH: Paraventricular nuclei
  2. GnRH : preoptic area
  3. PIH/PRH (Prolactin)

b.  Posterior
  1. ADH/ Oxytocin: supraoptic and paraventricular nucleus
  2. Both nuclei secrete both hormones; however,
  3. Paraventricular: mainly oxytocin
  4. Supraoptic: mainly ADH
Osmoreceptors: Anterior hypothalamus
These release cytokines from macrophages etc. → act on preoptic area of hypothalamus  release local
prostaglandins  fever
Autonomic nervous system
Stimulation of:
  1. The anterior hypothalamus
  2. Causes parasympathetic response like contraction of the urinary bladder
  3. Lateral areas of the hypothalamus
  4. Produces sympathetic responses such as rise in BP, pupillary dilation, piloerection, increased adrenal medullary secretion etc. this is the kind of response seen in animals exposed to stress (the fight or the flight reaction)
  5. Mid-dorsal area of the hypothalamus
  6. Causes cholinergic sympathetic vasodilatation
  7. Dorsomedial nuclei and posterior hypothalamic areas
  8. Produces increased adrenal medullary secretion which is one of the physical changes associated with rage and fear.

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