this is a detailed study on renal physiology , this explains about the functional anatomy & other functional aspects . please comment thank u

1. RENAL PHYSIOLOGY –
A DETAILED STUDY
PRESENTED BY
MARTIN SHAJI
PHARM D

2. 1.Filtration
2.Osmosis
3.toxins and metabolites
4.Wastes.
INTRODUCTION

4. Bean shaped
Hilus( the renal artery and renal nerves enter
through this and the renal vein exits from
here, lymphatic and the ureter leaves
through this region)
layers (outer cortex and inner
medulla)
FUNCTIONAL ANATOMY

5. Red in color
Highly vascular
Granular
Contains and bowman’s
capsule
And tortuous convoluted
tubules.
CORTEX

6. Pink in color
Less vascular
Striated appearance
Contains the largely straight running
portions of the nephrons.
MEDULLA

7. NEPHRON

8. Structural and functional unit o1the
kidneys
Each kidney has 1 million nephrons
They never divide during the Lifetime.
Each nephron is about 5 cm long
The total length of the nephrons s
about 100 kms

9. GLOMERULUS & BOWMANS
CAPSULE

10. It is composed of the loops of the arterioles
Arises from the afferent arteriole of each
nephron.
Glomerular capsule is the bowman’s capsule.
Glomerulus and the Bowman’s capsule are
together called the malpighian body.
The endothelial wall shows some
fenestrations of 40-100nm ¡n dia.
This surface prevents the large molecules to
escape into the filtrate.
This fluid after reabsorption and secretion
becomes urine.

11. URINARY TUBULE

12. Urinary tubules are divided into
number of segments
Basis of type of epithelium that lies
the lumen.
Basement membrane is same as in the macula densa.

13. This is the first portion of the tubule
It is lined by the cells which look le
truncated pyramids
Basically it has a large no of microvilli
which increase the surface area arid reabsorb a lot of
filtrate by active transport carried out by a large number
Mitochondria
Absorbs 2/3 of the glomerular filtrate,
1
PROXIMAL CONVOLUTED
TUBULE

14. The proximal convoluted narrows
abruptly to continue as the loop of
Henle.
The majority of the nephrons originate
in the cortex the loops of Henle are
short.
For the nephrons that originate in te
junction of cortex and medulla have
long loops of henle.
LOOP OF HENLE

15. Not very high metabolic activity.
Reabsorbs less than 1 5%of the filtrate.
Poor permeability
Reabsorbs against high order of the
gradients
Important part in final composition of the
urine
Small part of the distal tubule id near tie
afferent arteriole is called the macula’
densa.
DISTAL CONVOLUTED TUBULE

16. The proximal part of the collecting
tubules are very similar to the distal
part of the distal tubule
And the cells become columnar and
less mitochondria are present.
And this part shows less hormone
mediated reabsorption of the filtrate
COLLECTING DUCT

17. RENAL CIRCULATION

18. The mnemonic A WET BED aids h
memory of kidneys functions.
A — maintaining ACID-base balance
W — maintaining WATER balance
E — ELECTROLYTE balance
T — TOXIN removal
B — BLOOD Pressure control
E — making ERYTHROPOIETIN
D — Vitamin D metabolism.
FUNCTIONS OF KIDNEY

19. Secretion of hormones
Secretion of erythropoietin, which
regulates blood cell production in
the bone marrow .
Secretion of , which is a key part of the renin –angiotensin-
aldosterone system
Secretion of the active form of vitamin
D (calcitriol) and prostaglandin )

20. Gluconeogenesis
The kidney in humans is capable of producing glucose from
lactate, glycerol and glutamine.
The kidney is responsible for about half of the total
gluconeogenesis in fasting human The regulation of glucose
production in the kidney is achieved by action of , and other
hormones.
Renal gluconeogenesis takes place in
the renal cortex.
The renal medulla is incapable of producing glucose due to
absence of necessary enzymes

21. HOMEOSTASIS

22. The major homeostatic control point
maintaining this stable balance is renal
excretion.
Action of aldosterone, antidiuretic
hormone (ADH, or vasopressin), atrial natriuretic peptide
(ANP)& other hormones.
abnormal ranges of the fractional excretion of sodium can
imply acute tubular
excretion of sodium can imply acute.
tubular
necrosis or glomerular dysfunction

23. URINE FORMATION

24. Filteration
The is filtered by nephrons ,
of ultrafiltration , leaving an ultra filtrate
that resembles plasma (except that the ultra filterate has
negligible plasma proteins ) to enter bowman's capsule
Filtration is driven by starling forces .
The ultra filtrate is passed through, in turn, the proximal
convoluted tubule ,and a series,
of collecting duct to form urine

25. Reabsorption
Tubular reabsorption is the process by Which solutes and
water are removed from the tubular fluid and transported in to
the blood .it is called reabsorption (and not absorption) cause
these substances have already been absorbed once
(particularly in the intestines).
Reabsorption is a two-step process beginning
with the active or passive extraction of substances from the
tubule fluid in to the renal intestitium ( the connective tissue
that surround the nephrons ), and then transport of these
substances from the interstitium in to the bloodstream.
These transport processes are driven by starling forces
,diffusion & transport.

26. Indirect reabsorption
In some cases, reabsorption is indirect. For example,
bicarbonate (HCO3
−) does not have a transporter, so its
reabsorption involves a series of reactions in the tubule lumen
and tubular epithelium. It begins with the active secretion of a
hydrogen ion (H+) into the tubule fluid via a Na/H exchanger:
•In the lumen
• The H+ combines with HCO3
− to form carbonic acid
(H2CO3)
• Luminal carbonic anhydrase enzymatically converts
H2CO3 into H2O and CO2
• CO2 freely diffuses into the cell

27. •In the epithelial cell
• Cytoplasmic carbonic anhydrase converts the CO2 and
H2O (which is abundant in the cell) into H2CO3
• H2CO3 readily dissociates into H+ and HCO3
−
• HCO3
− is facilitated out of the cell's basolateral
membrane

28. . Some key regulatory hormone
reabsorption include:
Aldosterone which stimulates active sodium
reabsorption (and water as a result)
Antidiuretic hormone which stimulates passive water
reabsorption
• Both hormones exert their effects principally on
the collecting ducts
HORMONES

29. Secretion
Tubular secretion is the transferred of materials from
peritubular lumen
Tubular secretion is caused mainly by active transport.
Usually only a few substances are
secreted. These substances are
present in great excess, or are natural
poisons.
Many drugs are eliminated through urine.

31. THANK YOU