2. • 29 different types of elements in our body.
• Divided into 4 Major Groups
• Group I:- C, H, O, N
- Component of Macromolecules such as
Carbohydrates, Proteins and Lipids
• Group II :- (Macro Elements)
- Includes., Na , K , Cl ,Ca , P , Mg & S
- Required in amount > 100 mg/day
- Deficiency leads to fatal complications/death
3. • Group III :- (Trace Elements)
- Required in amount < 100 mg/day
- Includes., Co (Cobalt), Cr (Chromium), Cu
(Copper), I (Iodine), Fe (Iron), Mn (Manganese),
Mo (Molybdenum), Se (Selenium) & Zn (Zinc)
• Group IV:- (Additional Trace Elements)
- Exact role is unknown
- Cd (Cadmium), Ni (Nickel), Sn (Stensium),
Vn (Vanadium)
4. Metabolism of Minerals
Common minerals found active in body are
Na+, K+, Cl, Ca++ Fe++, P, Mg++, etc.
Ca++, P, Mg, Constituent of bones and teeth
Fe++:- Important element present in heme
compounds such as Hb , Cytochromes etc.
Deficiency of Minerals result in disturbance
of Physical Structure, Metabolic processes
and Normal functioning of body
5. • GENERAL FUNCTIONS OF MINERALAS
• Structural components of body i.e., They
perform building function e.g., Ca, P are
used in Bone formation, F for Teeth, P, K, Cl
& S for Tissues. S also for Hair, Nail; Fe for
Hb; Cl for HCl secretion & I for Thyroid
Hormones.
• Acid/Base Balance:- [NaH2PO4/NaHPO4]
• Regulates body fluids e.g in H2O Balance
• For the transport of Gases
• Responsible for Contraction & Relaxation
• As a Co-factor of certain Enzymes
7. Dietary Sources
• Milk and milk product------Best dietary source
• Other good Sources are Egg yolk, Beans, Nuts
& hard drinking water .
• Leafy vegetables:- (also contain oxalate &
benzoate), which are insoluble and thud
decrease its absorption
Body Distribution
• Human body contain about 1 Kg Ca2+
• 99 % in bones
• 1 % in extra cellular fluid .
8. Bone Ca2+:
In form of Hydroxyappetite Crystal [(Ca)6(PO4)3(OH)]
Bones perform two main functions:-
• Mechanical Functions
• Reservoir of Ca2+
1 % of bone Ca 2+ & 1 % of periosteal space Ca2+
is freely exchangeable with E.C.F & this is called
Miscible Pool of Ca2+
This exchange is regularized by P.T.H, Calcitriol,
& also by Calcitionin
9. Calcium in Plasma
[9 – 11 mg /dL]
R.B.C contains very little Ca2+
Extracellular concentration = 5m mol/L
Intracellular concentration = 0.1 – 10 µ mol/L
Ca2+ in plasma Exists in 3 forms
• Protein Bound Ca2+ [47%]
Mostly albumin (80%), Serum globulin (20%) and
Normal Level is 3.4 – 4.4 mg/dL
10. B. Complex Calcium [6%]
Complexed with plasma anions e.g., Citrate &
Phosphates etc. (0.5 – 0.7 mg/dL)
C. Ionized, Diffusible or Free Ca2+ [47%]
Biologically active from
• All 3 forms of Ca2+ in plasma remain in
equilibrium with each other
• Solubility product of Ca2+ i.e., Ca x P in serum
is a constant value
• It gives protection against precipitation of
Ectopic Calcification
11. Absorption:
• Ca2+ is taken in diet principally as calcium
phosphate, carbonates & tartarate.
Only 40% of dietary Ca2+ is absorbed mainly
from duodenum & first half of jejunum against
electrical and concentration gradients
Mechanism:
Two mechanisms for absorption
• Simple diffusion
• Active transport process
12. Both the process required Calcitriol and also a
Ca2+ dependent ATPase
Vitamin – D
Vit. D2: Ergocalciferol (Vegetables)
Vit. D3: Cholecalciferol (Animals origin/Inactive)
25 – Hydroxylase (Liver)
25–Hydroxycholecalciferol (Inactive)
1- α Hydroxylase
1, 25–Dihydroxy-Cholecalciferol/Calcitriol
(In Kidney)
13. Factor affecting absorption of Ca2+:
2. pH of Intestine
Acidic pH favors/increases absorption because
Ca2+ salt particularly PO4-3, carbonate are quite
soluble in acidic solution.
Alkaline pH decreases the absorption due to
form-ation of insoluble Tricalcium PO4-3
2. Composition of Diet
High protein diet: Increases absorption
because a.a (lysine & arginine) increases
solubility of Ca2+ salt
14. F. Acids decreases insoluble calcium soap
Sugars & organic acids increases absorption
Phytic acids decreases absorption
Oxalates present in vegetables also decreases
the solubility & hence decreases its absorpt.
5. Minerals
• PO4-3: Excess of PO4-3, decreases Ca2+ absorption
• Ca:P Ratio: For optimal absorption of Ca2+ ideal
ratio of Ca2+ to PO4-3 is 1:1 and it should not be
more then 2:1 and not less than 1:2
15. c) Fe in diet: forms insoluble Ferric phosphates
which decrease absorption
d) Vit–D: Increases absorption & serum Ca2+ level
4. State of Health & Aging:
- Healthy adult= 40% of dietary Ca+2
- above age of 60 years there is a gradual decline
- Ca+2 deficiency increases absorption probably
through increase Parathyroid activity
16. e) Bile salts: Increases Ca2+ absorption by
- Enhanced solubility of Ca2+ salts
- Increases Vit–D absorption
- Increases Digestion & absorption of fats
5. Hormones
(F) P.T.H:
• Stimulates “1-α Hydroxylase’’ enzyme in kidneys &
increase synthesis of Calcitriol which increase Ca2+
absorption from gut
• Direct effect on bone
• Direct effect on kidney.
17. (B). Calcitonin:
Increased level inhibits “1-α Hydroxylase’’ &
decrease calcitriol synthesis & decrease Ca2+
absorption.
Used in treatment of Hypercalcaemia caused by
hyperparathyroidism & Vit–D intoxication
(C) Glucocorticoids:
Decrease Ca2+ absorption by decrease intestinal
transport of Ca2+
18. • Factors affecting plasma Ca2+ Level
• Amount of Ca2+ absorbed from GIT
• P.T.H
• Increases mobilization of Ca2+ from bones
(Largest Effect)
• Increase absorption in gut (Long Term Effect)
(Increase the synthesis of Calcitriol)
• Decrease execration by kidney (Most Rapid
Action)
c. Inverse relationship b/w plasma Ca2+ & Pi. When
plasma Ca increase, P decrease & vice versa so
product of plasma Ca2+, & Pi remain constant at
30–40 mg/dL in adult 40–55 mg/dL in children.
19. [Plasma Ca2+ level falls in kidney diseases due
to retention of PO4-3 so increase PO4-3,
decreases Ca2+]
• Serum Protein Level: 1 gm serum protein
bound 0.84 mg of Ca2+. However ionized Ca2+
remain normal so there will be no Tetany,
when there is deficiency of protein
• Calcitonin: It decrease serum Ca2+ by
antagonizing the action of PTH. It decrease
bone resorption & increase deposition of Ca2+
in bones (It inhibits 1-α Hydroxylase)
20. Mechanism of action of Calcium:
Intracellular Ca2+ binds Calmodulin (4 binding Sites)
Ca–Calmodulin Complex
Active Calmodulin Kinase
Catalyze formation of Phosphoprotein from
Protein [Phosphoprotein exert their
Physiological & Biological response]
21.
22. • Functions of Calcium
2. Calcification of Bones and Teeth
3. Play imp. Role in Blood Coagulation
• A number of enzymes are activated by
blood Ca2+ e.g., Lipase, Succinic
dehydrogenase & few Proteolytic enzymes
• Play role in muscle contraction
• Transmission of nerve impulse
• Help in acid base balance
• Essential for release of certain hormones &
also for intracellular action of certain
hormones
23. 1. Essential for permeability of gap–junction
2. Membrane integrity & membrane transport
Excretion
Mainly excreted in faeces (0.4–0.8 g/day) ,
which is unabsorbed form.
Urinary loss is 150 – 200 mg/day.
Men working in extreme heat may loss 100 mg/
hr of Ca2+
Requirement: [1g/day]
Increase in pregnancy, lactation, & in children
24. • Hypercalcaemia: Various causes
• Ca get deposited in various body tissues
resulting in their malfunction
• Hypocalcaemia:
Low plasma ionized Ca2+:--- Tetany,
characterized by spontaneous firing of Nerve
fiber. Increase Cardiac contractibility,
retardation of relaxation of muscles etc.
Corpopedal Spasm
If untreated my lead to death. Spasm due to
respiratory muscles. I/V Calcium is treatment
