Pituitary and Hypothalamus

 

The Endocrine System.

Hypothalamus.
The hypothalamus is a part of the brain located inferior to the thalamus.

It serves many different functions in the nervous system, and is also responsible for the direct control of the endocrine system through the pituitary gland.

The hypothalamus contains special cells called neurosecretory cells that secrete hormones:                      

1. Thyrotropin-releasing hormone (TRH)
2. Growth hormone-releasing hormone (GHRH)
3. Growth hormone-inhibiting hormone (GHIH)
4. Gonadotropin-releasing hormone (GnRH)
5. Corticotropin-releasing hormone (CRH)
6. Oxytocin
7. Antidiuretic hormone (ADH) 

 

All of the releasing and inhibiting hormones affect the function of the anterior pituitary gland.

1.TRH stimulates the anterior pituitary gland to release thyroid-stimulating hormone.

2. and GHIH work to regulate the release of growth hormone—GHRH stimulates growth hormone release, GHIH inhibits its release.

3.GnRH stimulates the release of follicle stimulating hormone and luteinizing   hormone .

  4. CRH stimulates the release   of adrenocorticotropic hormone.

The last two hormones—oxytocin and antidiuretic hormone—are produced by the hypothalamus and transported to the posterior pituitary, where they are stored and later released. 

 

Pituitary Gland

The  pituitary gland, also known as the hypophysis, is a small pea-sized lump of tissue connected to the inferior portion of the hypothalamus of the brain.

   The pituitary gland is actually made of 2 completely separate structures: the posterior and anterior pituitary glands.

 

1.Anterior Pituitary:

The anterior pituitary gland is the true glandular part of the pituitary gland.

 The function of the anterior pituitary gland is controlled by the releasing and inhibiting hormones of the hypothalamus.

The anterior pituitary produces 6 important hormones:

o    Thyroid stimulating hormone (TSH), as its name suggests, is a tropic hormone responsible for the stimulation of the thyroid gland.

o    Adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex, the outer part of the adrenal gland, to produce its hormones.

o    Follicle stimulating hormone (FSH) stimulates the follicle cells of the gonads to produce gametes—ova in females and sperm in males.

o    Luteinizing hormone (LH) stimulates the gonads to produce the sex hormones—estrogens in females and testosterone in males.

o    Human growth hormone (HGH) affects many target cells throughout the body by stimulating their growth, repair, and reproduction.

Prolactin (PRL) has many effects on the body, chief of which is that it stimulates the mammary glands of the breast to produce milk.

 

 

2.Posterior Pituitary: The posterior pituitary gland is actually not glandular tissue at all, but nervous tissue instead.

These neurosecretory cells secret 2 hormones in the hypothalamus that are stored and released by the posterior pituitary: 

 1. Oxytocin 

        2.Antidiuretic hormone (ADH) 

 

 

 

 

 

Disorders of Pituitary Gland

Parts involved	Hyperactivity	Hypoactivity
Anterior Pituitary	1.    Gigantism 2.    Acromegaly 3.    Acromegalic gigantism 4.    Cushing’s disease	5.    Dwarfism 6.    Acromicria 7.    Simmond’s disease
Posterior Pituitary	Syndrome of inappropriate hypersecretion of ADH (SIADH)	Diabetes insipidus
Anterior and Posterior Pituitary	…….	Dystrophia adiposogenitalis

Aaharparinamkar Bhav

Water soluble Vitamin

Vitamin name	Scientific name	Daily Requirement	Deficiency Disorders
Vitamin B1	Thiamine	1.o-1.5 mg	Beriberi.
Vitamin B2	Riboflavin	1.2 -1.7mg	Glossitis, Angular stomatitis
Vitamin B3	Niacin, Nicotinamide	10-15mg	Pellagra[D3]
Vitamin B5	Pantothenic acid	10 mg	Paresthesia
Vitamin B6	Pyridoxine, Pyridoxamine, Pyridoxal	1.5mg	Anemia,,peripheral neuropathy.