Neuropeptide Y (NPY) is a 36 amino acid peptide that is widely distributed throughout the central and autonomic nervous systems. It has five receptor subtypes and diverse functions including regulating food intake, blood pressure, stress responses, and hormone secretion. NPY was first identified in porcine brain extracts in 1978 and is implicated in several disorders such as feeding disorders, seizures, hypertension, and depression. It is highly expressed in sympathetic ganglia and tissues with dense sympathetic innervation. NPY stimulates food intake and meal size while delaying satiety. It may also play a role in obesity, alcoholism, and linking stress and diet by triggering cravings for high fat foods during periods of stress.

1. NEUROPEPTIDE Y
Bhagya Siripalli, Pharmacology,
SVIPS.

2. Introduction
 36 amino acid peptide with structural similarities to Peptide YY
(PYY) and pancreatic polypeptide (PP).
 Widely distributed throughput CNS and ANS.
 Five subtypes- Y1, Y2, Y4, Y5, Y6
 Diverse functions including food intake, blood pressure, circadian
rhythms, stress pain, hormone secretion, reproduction, alcohol
consumption.
 Also implicated in number of disorders such as feeding disorders ,
seizures, hypertension, pain, depression, anxiety.

4. Discovery
o Identified in the porcine brain extracts.
o 1978- novel method developed for the detection of biologically
active peptides based on C- terminal amide structure.
o 1980- 2 peptide amide- HI (PHI) AND PYY
o 1982- peptide with C- terminal tyrosine amide-NPY
o 1983- Galanin
o 1985- NPK
o 1986- Pancreastitin.

5. Distribution
 CNS
• brain- cortex, hippocampus, hindbrain, hypothalamus
 ANS
• high levels of NPY found in sympathetic ganglia and in tissues receiving a
dense sympathetic innervations, such as
o Vas deferens
oHeart atrium
oBlood vessels, spleen
oKidney
oRespiratory
oUrogenitary tracts
oVisceral smooth muscle
o Neuronal elements of gut and pancreas.

7. Receptors
o NPY operates on is a G protein-coupled receptor in the rhodopsin
like 7-transmembrane GPCR family.
o Five subtypes of the NPY receptor have been identified in
mammals, four of which are functional in humans.
o Subtypes Y1 and Y5 have known roles in the stimulation of
feeding
o Subtypes Y2 and Y4 seem to have roles in appetite inhibition
(satiety).
o Some of these receptors are among the most highly conserved
neuropeptide receptors.

9. Functions
 Role in food intake
- it stimulates food intake with preferential effect on
carbohydrate
- it decreases latency to eat, increases motivation to
eat, delays satiety by augmenting meal size.
 Role in obesity
-an increase in glucocorticosteroid concentrations in
plasma;
-insensitivity or resistance to insulin;
-mutation of leptin receptor; and
-an increase in NPY mRNA and NPY release.

11.  Role in alcoholism
-NPY might protect against alcoholism
 Correlation with stress and diet
-large amounts of NPY are released which may
interfere with immune defense mechanism
-this explains why we tend to eat more than what our body
needs when exposed to different levels
and types of stress
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12. Neuropeptide Y, in addition to cortisol triggers crave for salty, sweet and
high fat
-The more uncontrolled stress in your life, the more likely you are to turn
to food for emotional relief.

13. Thank you