ENDOCRINE_GLANDS_II clear

ENDOCRINE_GLANDS_II clear - MBBS PRGRAM DEPARTMENT OF...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
MBBS PRGRAM DEPARTMENT OF ANATOMY ENDOCRINE GLANDS Presented By PROF Dr / YOUSRY M SHAWKY
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of EG : 1. They have NO ducts and discharge their secretion (hormones) directly in blood. 2. They have rich blood Supply. 3. They are simple in structure: They consist of cords and plates of cells separated by blood vessels. ENDOCRINE GLANDS
Background image of page 2
It is a reddish-grey, ovoid body, about 12 mm in transverse and 8 mm in anteroposterior diameter and weighs about 500 mg. It lies within the hypophyseal fossa of the sphenoid bone. It is covered superiorly by a diaphragma sellae of dura mater which is pierced centrally by the infundibulum and separates the gland from the optic chiasma. Inferiorly & in front it is related to the sphenoid air sinus. It is related on either side to the cavernous sinus. It is related behind to dorsum sellae. Pituitary Gland (Hypophysis Cerebri)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The pituitary gland consists of : A) Anterior lobe (adenohypophysis) : Consists of: - Pars distalis - Pars tuberalis - Pars intermedia B) Posterior lobe (neurohypophysis) : Consists of pars nervosa which is connected by infundibulum (pituitary stalk) to the median eminence (tuber cinereum) of hypothalamus.
Background image of page 4
Pars distalis is formed of : Thick irregular cords of cells + blood sinusoids There are 2 types of cells: a) Chromophobes: About 50% of the cells. They are small, found in groups and have NO GRANULES in their cytoplasm. b) Chromophils: The other 50% of the cells. They have GRANULES in their cytoplasm and are larger than the chromophobes.There are 2 types of chromophil cells: — ACIDOPHILS (10%): have reddish cytoplasm. They secrete growth hormone (GH) & Prolactin (lactogenic) H. — BASOPHILS (40%): have bluish cytoplasm. They secrete TSH, ACTH, FSH & LH. In general basophils are larger in size and stain deeper than the acidophils.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Cells and hormones of the anterior pituitary gland & their functions Cell Hormone secreted Function Somatotropes (Acidophilic) Growth H (somatotropin) Stimulates body growth Mammotropes (Acidophilic) Prolactin (PRL) Stimulates milk production & secretion Thyrotropes (Basophilic) Thyroid Stimulating H (TSH) Stimulates production of thyroid H by follicular cells Gonadotropes (Basophilic) -Follicle Stimulating Hormone (FSH. -Luteinizing H (LH) -Stimulates follicular cells in ovary & spermatogenesis in testis. - Stimulates production of estrogen & progesterone from the ovary & testosterone from the testis Corticotropes (Basophilic) Adreno-Cortico Trophic H (ACTH or corticotropin) Stimulates secretion of glucocorticoids & androgens from adrenal cortex
Background image of page 6
Pars nervosa contains : a) Bundles of nerve fibers. b) Cells called pituicytes. c) homogenous intercellular
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 27

ENDOCRINE_GLANDS_II clear - MBBS PRGRAM DEPARTMENT OF...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online