Explain the magnesium deficiency and toxicity, Biology

Assignment Help:

Explain the Magnesium Deficiency and Toxicity?

Deficiency of magnesium is rare for two reasons: frstly, the mineral is widely distributed in the foods, secondly, kidney is able to adjust re-absorption of filtered magnesium to body needs. However, Mg depletion occurs in 'various conditions, which either inlpair its intestinal absorption or increase its urinary excretion. Studies have shown that a decline in urinary magnesium excretion during protein- energy malnutrition (PEM) is accompanied by a reduced intestinal absorption of magnesium. The catch-up growth associated with recovery from PEM is achieved only if magnesium supply is increased substantially. Most of the early pathological consequences of depletion are neurologic or neuromuscular defects, some of which probably reflect the influence of magnesium on potassium flux within tissues. Thus, a decline in magnesium status produces anorexia, nausea, muscular weakness, lethargy, staggering and if deficiency is prolonged, weight loss. Progressively increasing with the severity and duration of depletion are manifestations of hyperirritability, hyperexcitability, muscular spasms, and tetany, leading ultimately to convulsions.

An increased susceptibility to audiogenic shock is common in experimental animals. Cardiac arrhythmia and pulmonary oedema frequently have fatal consequences. It has been suggested that a suboptimal magnesium status may be a factor in the etiology of coronary heart disease and hypertension but additional evidence is needed. Hypomagnesernia associated with deficiency represents a plasma Mg levels of less than 1.5 mg/dl. It leads to impaismeilt in Ca and K homeostatsis. Hypocalcernia and hypokalemia have been observed in both experimentally produced and disease-related Mg deficiency. These disturbances are partially caused by hypomagnesemia induced changes in the production and function of PTH. Reduced serum Mg initially stimulates parathyroid gland to produce more PTH, but as deficiency becomes more severe, the sensitivity of parathyroid gland to slow serum Ca concentration is impaired and level of PTH .is low in relation to degree of hypocalcernia. Decreased Mg status has been suggested as a factor contributing to the pathogenesis of several chronic diseases. Both dysrhythmias and myocardial ischemia have been attributed to low Mg intakes. Hypomagnesemia in diabetes may be one of the risk factors in the development of diabetic retinopathy.


Related Discussions:- Explain the magnesium deficiency and toxicity

Differentiate individual atoms true or false, What is the first step normal...

What is the first step normally taken when you look through the oculars? The nuclei of the cheek cells have been stained using a special dye so that they appear purple. What is the

What are the stages into which photosynthesis is divided, What are the stag...

What are the stages into which photosynthesis is divided? Photosynthesis is separated into the photochemical stage, or light reactions, and the chemical stage. Photosynthesi

What would be the short- and long-term effects, In a possible future scenar...

In a possible future scenario, male fertility drops to zero, but, luckily, scientists develop a way for women to produce babies by virgin birth. Meiocytes are converted directly (w

Define about the eukaryotic cell, The eukaryotic cell The eukaryotic ce...

The eukaryotic cell The eukaryotic cell is a complex unit and contains many structural features not seen in in the simple prokaryotic cell. Fig below shows the details of vario

Explain brifly ribosomes- endoplasmic reticulum , Explain brifly Ribosomes,...

Explain brifly Ribosomes, Endoplasmic Reticulum, Golgi Apparatus ? Ribosomes, Endoplasmic Reticulum, Golgi Apparatus :  The cytoplasm contains many ribosomes, which are sphe

Define the nutritional needs of microorganisms, Define the Nutritional Need...

Define the Nutritional Needs of Microorganisms? About 95% of dry cell weight of microorganisms is constituted by macro elements. These are carbon (C), nitrogen (N), oxygen (O),

Explain the concept behind freezing the milk, Concept behind Freezing the m...

Concept behind Freezing the milk Freezing the milk also alters its composition and properties to a great extent. Let us learn about these changes. As the milk freezes, it becom

What is micrographia?, Micrographia is abnormally small, cramped handwritin...

Micrographia is abnormally small, cramped handwriting and/or the progression to continually smaller handwriting. This is one of the symptoms of Parkinson''s disease.

Characteristics of lake ecosystems, Characteristics of Lake Ecosystems ...

Characteristics of Lake Ecosystems The environment of static waters of lakes and ponds sharply contrasts with those of lotic ecosystems. Light penetration in lakes is usually

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd