The document discusses creatine and creatinine, explaining that creatine is stored in muscles and converted to creatine phosphate to provide energy, while creatinine is a breakdown product of creatine. It covers the biosynthesis and metabolism of creatine, the reversible reaction between creatine and creatine phosphate, and the use of creatinine levels in blood and urine as indicators of kidney function and muscle mass. The document also discusses creatine kinase isoenzymes and their role in converting creatine to creatine phosphate.

1. Energetics
Creatinine Phosphate
Represented By,
Mr. Audumbar Mali,
(Asst. Prof.)
Sahyadri College of Pharmacy Methwade
1

2. 1. To study the importance of creatine in
muscle as a storage form of energy
2. To understand the biosynthesis of creatine
3. To study the process of creatine degradation
and formation of creatinine as an end product
4. To understand the clinical importance of
creatinine as a sensitive indicator of kidney
function
5. To study different types of creatine kinase (CK)
and their clinical importance
Objectives

3. What’s Creatine and Creatinine
•Creatine and creatinine are not the
same substance!
•Creatine is found in the muscles…….
•Creatinine is a break-down product (a
waste product) of creatine phosphate
and creatine in muscles, and is usually
produced at a fairly constant rate by the
body depending on muscle mass.

4. 1. The creatine is an
amino acid that does
not found in proteins.
2. Creatine is a nitrogenous
organic acid

5. Three amino acids are required: Glycine,
Arginine, Methionine (as S-adenosylmethionine)
Site of biosynthesis: Step 1: Kidneys
Step 2: Liver
Creatine
Biosynthesis

6. Where:- SAM : S‐adenosyl methionine.

7. Distribution of body
creatine
From liver, transported to other tissues
98% are present in skeletal and heart muscles
In Muscle, gets converted to the high energy
source creatine phosphate (phosphocreatine)
Creatine
Creatine phosphate
ATP
ADP
ATP
CreatineKinase
ADP+ H+

8. What’s the Relationship between
Creatine and Creatine phosphate?
Creatine and creatine phosphate exist in a reversible
equilibrium in skeletal muscle.
In skeletal muscle, approximately one-fourth of
creatine exists as free creatine and three fourth exists
as creatine phosphate.

9. The Reversible Equilibrium between
Creatine and Phosphocreatine

10. CreatinePhosphate
Is a high-energy phosphate compound
Acts as a storage form of energy in the
muscle
Provides a small but, ready source of
energy during first few minutes of intense
muscular contraction
The amount of creatine phosphate in the
body is proportional to the muscle mass

12. 1. Creatine and creatine phosphate spontaneously
form creatinine as an end product.
2. Creatinine is excreted in the urine.
3. Serum creatinine is a sensitive indicator of kidney
disease (Kidney function test).
4. Serum creatinine increases with the impairment of
kidney function.
Creatine Degradation

13. CreatineDegradation
Creatine
Creatine phosphate
ATP
ADP+ H+
ATP
ADP
CreatineKinase
Creatinine
H2O
Pi
Plasma
Glomerular
filtration
Urine

14. CREATININE EXCRETION
The creatinine is a waste product of creatine
phosphate and it will be excreted by the kidney in the
urine at a rate of 1 to 2 g/day.

15. Creatinine
Metabolism

16. TheDiagnosticFunctionof Creatinine

17. How is Creatinine Used to
Monitor Renal Function…?

18. Levels of Creatinine
in the Blood
Depends Mainly on
Renal Function.

19. Serum Creatinine may be
Affected Partly by….
The amount of muscle tissue you have
maintend to higher levels of blood
creatinine because they have more
skeletal muscle tissues than women.
Protein in diet: - Vegetarians have been
shown to have lower creatinine levels
in blood.

20. CreatineKinase(CK)
CK is responsible for the generation of energy in
muscular tissues.
CK levels are changed in disorders of cardiac and
skeletal muscle.
Creatine
Creatine phosphate
ATP
ADP
ATP
CreatineKinase
ADP+ H+

21. Creatine Kinase(CK)
1. CK is required for conversion of creatine into
creatine phosphate
2. CK has 3 isoenzymes:
CK-MM
CK-MB
CK-BB
mainly in skeletal muscle
mainly in heart muscle
mainly in brain
3. Serum total CK is increased in:
Crush injuries (Damage of skeletal muscles)
Myocardial infarction (Damage of heart muscle)

22. Diagnostic Value: CK is present in all
tissues but only SELECTIVE
RELEASE (brain, muscle but not
liver) therefore different from liver
damage caused by: MI, muscle
trauma, muscle dystrophy, severe
exertion, hypothyroidism, chronic
alcoholism.

23. Creatinine in urine and
plasma
Normal serum creatinine level is 0.7 to 1.4 mg/dl and serum
creatine level is 0.2 to 0.4 mg/dl
The amount of creatinine excreted is proportional to the total
creatine phosphate content of the body
therefore can be used to estimate muscle mass
Serum creatinine is a sensitive indicator of kidney disease
(Kidney function test)
Because normally creatinine is rapidly removed from the blood
and excreted
The amount of creatinine in urine is used as an indicator for
the proper collection of 24 hours urine sample.

24. References:
Human Anatomy and Physiology, By
Dr. S. B. Bhise, Dr. A. V. Yadav. Nirali
Prakashan, As per PCI Syllabus,
Page No. 3.5-3.6.
https://www.slideshare.net/khaledalg
ariri/creatine-metabolism
https://www.slideshare.net/Urendersi
ngh/creatinine-estimation

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