Article overview hypothalamus
- What is the hypothalamus?
- What is the function of the hypothalamus?
- Where is the hypothalamus?
- What problems can the hypothalamus cause?
What is the hypothalamus?
The hypothalamus is an area of the diencephalon. It consists of collections of nerve cells (nuclei), which act as switching stations for the leading and trailing pathways to other parts of the brain. For example, information about the hypothalamus flows from the hippocampus, the almond body (amygdala), the thalamus, the striatum, the cerebral cortex of the limbic system , the middle and hindbrain and the spinal cord.
Outgoing information flows from the hypothalamus to the midbrain and thalamus as well as to the neurohypophysis (posterior pituitary gland).
In the hypothalamus, all known in the body periphery hormones can be detected.Different Types of Headaches Top 3 most common headache forms. How they arise and when to go to the doctor better. The top 3 most common types of headaches. How they develop and when you should go to the doctor better. To the table of contents
What is the function of the hypothalamus?
The hypothalamus is the mediator between the hormone and the nervous system. The hypothalamic hormones control, for example, the sleep-wake rhythm, the feeling of hunger and thirst, but also the sex drive and pain sensations. The thermoregulation of the body also starts from the hypothalamus.
Information from various measuring stations in the body on blood sugar, blood pressure, temperature and much more converge in the hypothalamus, which can then send signals to release certain hormones for regulation. These hypothalamic hormones are divided into three groups:
The first group of hypopthalamic hormones, the so-called effector hormones, include oxytocin and adiuretine. Oxytocin stimulates labor at birth as well as the injection of breast milk into the breast. Adiuretin is responsible for water reabsorption in the kidney. Both hormones are synthesized in the hypothalamic nuclei, then transported to the posterior pituitary, from where they are released into the systemic circulation.
The second group of hypothalamic hormones are control hormones: various releasing (release) hormones stimulate the pituitary gland to synthesize and secrete various hormones. Inhibiting hormones inhibit the secretion of pituitary hormones.
Other neuropeptides from the hypothalamic neurons, together with the first or second group, affect the function of the anterior pituitary or act as communicators between the hypothalamus and other areas of the brain.
Control circuits ensure order
The effects of hormones must always be precisely tailored to the needs of the organism. Therefore, the systems of synthesis, secretion, receptor, transport to the target organ and the metabolism of each hormone must be exactly matched. To achieve this, there are control loops that influence all of this, including, in particular, the hypothalamic-pituitary system.
In addition to many other regulatory circuits, thermoregulation is important to the organism to maintain a core temperature of about 37 degrees Celsius. The core temperature of the body must - within certain limits - always be constant. To achieve this, the body has "sensors" in the skin and in the organs - free nerve endings of sensitive nerve cells. Their information is transmitted to the thalamus and then to the hypothalamus.
If the body core temperature drops, a control loop for temperature regulation starts. The hypothalamus stimulates the pituitary anterior lobes with the help of a specific hormone to release the hormone TRH (thyrotropin releasing hormone). TRH secretes the hormone TSH in the pituitary via a control circuit, which in turn stimulates the secretion of thyroxine (T4) from the thyroid gland. T4 enters adipose tissue and skeletal muscle and is converted to triiodothyronine (T3). T3 causes an increase in the basal metabolic rate, leads to increased energy supply from the liver, increases the heart rate - with the result of an increase in temperature.
When the body core temperature increases, the hypothalamus reduces the sympathetic tone, which widens the vessels in the periphery and promotes sweat secretion, resulting in a cooling of the body.