REGULATION OF

OSMOLARITY

ANMOL JILANI

OSMOLARITY:

It is the measure of solute concentration, defined as the number of osmoles of solute per litre of solution.

Normal Value: 300mOsm/L

CONTROL OF ECF OSMOLARITY & SODIUM CONCENTRATION:

Regulation of ECF osmolarity & sodium concentration are closely related.

Osmolarity must be precisely controlled because they determine the distribution of fluid between intracellular and extracellular compartment.

REGULATION OF OSMOLARITY

ADH-hormone(Antidiuretic Hormone)Also called vasopressin

Thirst Mechanism

Aldosterone- hormone

Angiotensin II- peptide

OSMORECEPTOR-ADH FEEDBACK SYSTEM

ADH ACTS ON DISTAL TUBULE & COLLECTING DUCT

REGULATION OF ADH SECRETION

THIRST MECHANISM

Many of same factors that stimulate ADH secretion also increase thirst,which is defined as the concious desire for water.

THIRST MECHANISM

Dehydration

Osmolarity

Stimulus to thirst center

Water intake

ECF volume

CONTROL OF THIRST

ANGIOTENSIN II & ALDOSTERONE SYSTEM

THANK YOU