The hypothalamus is a small region of the brain located in the middle of the brain that regulates many important bodily functions through the hormones it produces or influences. It controls homeostasis by regulating body temperature, hunger, thirst, and hormones. Dysfunction of the hypothalamus can result from head trauma, tumors, infection, or malnutrition and can lead to disorders of energy balance, thermoregulation, sleep cycles, and pituitary hormone deficiencies. Recent research also suggests high-fat diets and obesity may damage neurons in the hypothalamus and impair its ability to regulate hunger and fullness.

1. Hypothalamus
Aya Al-Salem

2. Where is the hypothalamus located?
The hypothalamus is located in the middle of the brain. It is an
extremely complex part of the brain containing many regions
with highly specialized functions. In humans, the hypothalamus
is approximately the size of a pea.
• http://www.healthline.com/human-body-maps/hypothalamus

5. What is the function of the hypothalamus ?
The hormones from the hypothalamus manage
physiological functions such as temperature
regulation, and motivated behaviors like
thirst, hunger, sleep, mood, sex drive, and the
release of other hormones within the body.
This area of the brain households the pituitary
gland and other glands in the body.

6. What is the function of the hypothalamus ?
One of the major functions of the hypothalamus is to maintain homeostasis,
and to keep the human body in a stable, constant condition.
Note: Homeostasis, any self-regulating process by which biological systems
tend to maintain stability while adjusting to conditions that are ideal for survival. If
homeostasis is successful, life continues; if unsuccessful, disaster
or death follows.

7. The hypothalamus responds to a
variety of signals from the
internal and external environment
including body temperature,
hunger, feelings of being full up
after eating, blood pressure and
levels of hormones in the
circulation.

8. It also responds to stress and controls our daily bodily rhythms
such as the night-time secretion of melatonin (sleep
hormone) and the changes in stress hormones and body
temperature.
The hypothalamus collects and combines this information and
puts changes in place to correct any imbalances. And it links
between the endocrine and nervous systems.

9. What hormones does my hypothalamus
produce?
There are two sets of nerve cells in the hypothalamus that produce
hormones. One set sends the hormones directly into the bloodstream.
These hormones are anti-diuretic hormone and oxytocin. Anti-diuretic
hormone causes water reabsorption at the kidneys and oxytocin “love
hormone” stimulates contraction of the uterus in childbirth and is
important in breastfeeding (mother-child attachment).

10. The other set of nerve cells produces stimulating and inhibiting
hormones. These regulate the production of hormones that control
the gonads, thyroid gland and adrenal cortex, as well as the
production of growth hormone, which regulates growth,
and prolactin, which is essential for milk production.

11. The hormones produced in the hypothalamus are corticotrophin-
releasing hormone (central driver of the stress hormone system),
dopamine, growth hormone-releasing hormone, somatostatin (growth
hormone), gonadotrophin-releasing hormone (luteinizing hormone: It
plays a role in puberty, menstruation, and fertility.) and thyrotrophin-
releasing hormone (increases activity and decreases food intake, body
weight, and sleep, in part through hypothalamic actions)

12. More than a third of adults in the U.S. are obese. And many of those
already overweight continue to put on even more pounds. Now researchers
have a clue why.
Two new studies in the Journal of Clinical Investigation suggest how
obesity and high-fat diets might actually alter the way the brain works,
changing in particular the hypothalamus. This almond-sized area of the
brain helps regulate hunger and thirst, as well as sleep and body
temperature. So if it’s dysfunctional, people can feel hungry even when
they've consumed plenty.

13. One study found that in the brains of both obese humans and obese
rats, neurons around the hypothalamus were damaged by
inflammation. High-fat diets have been known to promote
inflammation throughout the body, but that usually takes weeks or
months to appear. Changes in the brain, however, can happen fast—
even within 24 hours. [Joshua Thaler et al, Obesity is associated with
hypothalamus injury in rodents and humans]

14. The second study found that mice on a fatty diet were slow to replace
old neurons in the hypothalamus, which could also hamper its
function. [David McNay et al., "Remodeling of the arcuate nucleus
energy-balance circuit is inhibited in obese mice"]

15. Hypothalamic function can be affected by
head trauma, brain tumors, infection,
surgery, radiation and malnutrition. It can
lead to disorders of energy balance and
thermoregulation, disorganized body
rhythms, (insomnia) and symptoms of
pituitary deficiency due to loss of
hypothalamic control.

16. Hypothalamus dysfunction
Complications of hypothalamic dysfunction
depend on the cause.
Brain tumors:
Permanent blindness
Problems related to the brain area where
the tumor occurs
Vision disorders

17. Hypothyroidism: such as obesity, joint pain, infertility and
heart disease
Heart problems
High cholesterol
Adrenal insufficiency:
Inability to deal with stress (such as surgery or infection),
which can be life-threatening by causing low blood pressure

18. Gonadal deficiency:
Heart disease
Impotence (weakness in men)
Infertility
Thin bones (osteoporosis)
Growth hormone deficiency:
High cholesterol
Osteoporosis
Short stature (in children)
Weakness

19.  Lack of anti-diuretic hormone production by the hypothalamus
causes diabetes. In this condition the kidneys are unable to
reabsorb water, which leads to excessive production of dilute urine
and very large amounts of drinking.

20. To sum up
 Heart rate and blood pressure
 Body temperature
 Fluid and electrolyte balance, including
thirst
 Appetite and body weight
 Glandular secretions of the stomach and
intestines
 Production of substances that influence
the pituitary gland to release hormones
 Sleep cycles

21. For more information go to :~
http://www.endocrineweb.com/endocrinology/overview-hypothalamus
http://www.healthline.com/human-body-maps/hypothalamus
http://www.cerebromente.org.br/n05/mente/struct_i.htm
http://www.yourhormones.info/glands/hypothalamus.aspx
http://www.scientificamerican.com/podcast/episode/fat-may-put-
hypothalamus-on-fritz-11-12-27/
https://www.nlm.nih.gov/medlineplus/ency/article/001202.htm