Hormones secreted by adrenal gland, Biology

Hormones. Cortical steroids (corticoids-hormones of adrenal cortex) are grouped into three catagories :

mineralocorticoids, glucocorticoids and gonadocorticoids.

(i) Mineralocorticoids. These hormones are secreted by the cells of zona glomerulosa of adrenal cortex.

  • They are responsible for the regulation of mineral metabolism.
  • Aldosterone (salt-retaining hormone) is the principal mineralocorticoid (90 to 95%) in humans. Aldosterone is a steroid.
  • Its main function is to regulate the sodium content of the body. It is secreted when the sodium level is low.
  • It acts on the kidneys to cause more sodium to be returned to the blood and more potassium to be excreted.
  • As the sodium concentration in the blood increases, water follows it by osmosis, so the blood volume also increases.
  • The effect of aldosterone is to increase both sodium and water in the blood.

Target cells. Mineralocorticoids act on the cells of the kidneys.

(ii) Glucocorticoids. They affect carbohydrate metabolism, however, they also affect the metabolism of proteins and fats.

  • Glucocorticoids include three main hormones: Cortisol (= hydrocortisone), corticosterone and cortisone.
  • Cortisol is the most abundant (about 95%).
  • It stimulates the liver to synthesize carbohydrates from noncarbohydrates such as amino acids and glycerol. Thus increases level of glucose in the blood.
  • Cortisol also stimulates the degradation of proteins within cells and amino acids in the blood, therefore, increases level of amino acids in the blood.
  • Cortisol is to stimulate the breakdown of fats in adipose tissue and release fatty acids into the blood.
  • Thus cortisol has anti insulin effect. It also helps in reducing pain.
  • Cortisol is anti-inflammatory. It retards phagocytic acitivities of WBCs and thus suppresses 'inflammation reaction'.
  • This hormone also reduces the number of mast cells, reducing secretion of histamine. This is also an antiinfammatory effect.
  • Cortisol is also "immunosuppressive". It suppresses synthesis of antibodies by inhibiting the production of lymphocytes in the lymphoid tissues.

Target Cells. Glucocorticoids act on the cells of the liver.

(iii) Gonadocorticoids (Sexcorticoids). They are also called sex hormones of adrenal glands. Large quantities of male than female sexcorticoids (sex hormones) are produced.

  • These male sex hormones are called androgens which are important in the development of a male foetus.
  • Androgens stimulate the development of male secondary sexual characters like distribution of body hair.
  • Female sex hormones secreted by the adrenal cortex are oestrogens which maintain the development of female secondary sexual characters.

Target cells. Gonadocorticoids act on the cells of gonads (testes and ovaries).

Posted Date: 10/2/2012 6:56:49 AM | Location : United States







Related Discussions:- Hormones secreted by adrenal gland, Assignment Help, Ask Question on Hormones secreted by adrenal gland, Get Answer, Expert's Help, Hormones secreted by adrenal gland Discussions

Write discussion on Hormones secreted by adrenal gland
Your posts are moderated
Related Questions
- Oogenesis involves the formation of haploid cells from an original diploid cell, called a primary oocyte, through meiosis. - The female ovaries contain the primary oocyte. The

What are the physio-chemical properties of vitreous? PHYSIO-CHEMICAL PROPERTIES OF VITREOUS: Vitreous is a clear gel like optically empty structure. Its physio-chemical prop

What is a population? A population is a set of individuals of the similar species found in a given place in a given time.

In the aerials competition in skiing, the competitors speed down a ramp that slopes sharply upward at the end. The sharp upward slope launches them into the air, where they perform

P o i s on i n g P e sticide toxicity Chemical pesticides were introduced as an important tool for pest control and have been used extensively in human health ope

Q. What is Technetium 99M Sestamibi Scan? This study is another form of studying perfusion of the heart. This radioactive study is similar to that of thallium 201. With a combi

Lorica - body form Protozoans It is a covering which unlike the theca fits loosely around the organism. It is a cup, bell or vase-like structure with one opening through which

Define Cercaria Larva? Cercaria  larva is the fourth  larval stage  in  the life-cycle of F, hepatica. It is a free living stage produced  by  the  redia  larva. 1. It has

Factors Controlling Stomatal Aperture 'Khul Ja Sim Sim' the two rocks slide and the gates to a great treasure open. With these magic words "Ali Baba and Chalis Chor" could ope

Explain the Modern Trends in Animal Taxonomy? Earlier you learnt how taxonomy is interrelated to other biological fields. You also learnt how information is used from other f