The document discusses the physiological roles of nitric oxide (NO) in various systems of the human body, including cardiovascular, immune, nervous, reproductive, respiratory, renal, endocrine systems, and its influence on hair growth and wound healing. Key functions of NO include its role in vasodilation, immune response, neurotransmission, sperm fertilization, enhancing blood flow, and promoting cellular functions. The document highlights the implications of NO in health and disease, citing relevant studies and references.

1. Nitric oxide-Physiological role
Presented by
S.Nagarajan,
3rd year BDS,
Ragas dental
college.
Guided by
Dr.Dharini,
Department of physiology,
Ragas dental college.

2. Nitric Oxide
Ragas Dental College2
 1988- Discovery of pathway
for NO synthesis
 1992-NO, named the molecule
of the year for its role in
treatment of CVS diseases.

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Production of NO

4. 1. ROLE IN CARDIOVASCULAR SYSTEM
2. ROLE IN IMMUNE SYSTEM
3. ROLE IN NERVOUS SYSTEM
4. ROLE IN REPRODUCTIVE SYSTEM
5. ROLE IN RESPIRATORY SYSTEM
6. ROLE IN RENAL SYSTEM
7. ROLE IN ENDOCRINE SYSTEM
8. ROLE IN WOUND HEALING
9. ROLE IN HAIR GROWTH
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ROLE OF NITRIC OXIDE IN
HUMAN PHYSIOLOGY

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ROLE IN CARDIOVASCULAR SYSTEM

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Inhibition of NO synthase (N-Mono methyl arginine) - long-lasting increase in blood
pressure which was reversed immediately by giving L-arginine. (©JOURNAL OF
THE ROYAL SOCIETY OF MEDICINE Volume 92 April 1999)

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2 ROLE IN IMMUNITY:
 Aids in killing of engulfed
pathogen.
 Inhibits Inflammation in
blood vessels.
In a study involving 15 treated hypertensive men and women, the use of
antibacterial mouthwash killed normal flora which interrupted the nitrate-nitrite-
NO conversion producing an elevation of systolic pressure in most of them.(©
American Journal of Hypertension, Ltd 2014).
Harmless bacteria, living as commensals in the gingival
crevice can convert nitrates in our food into nitrites and
finally produce NO which can kill the harmful bacteria in
oral cavity.
NITRIC OXIDE AND ORAL HYGIENE:

8. ROLE IN APOPTOSIS:
 NO either promotes or
prevent apoptosis
 High concentration:
promote apoptosis
 Low concentration:
inhibits apoptosis

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3 NITRIC OXIDE AND NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM:
 One of the neurotransmitters
 In severe hypoxia, NO-sensitive cells in the
medulla oblongata respond to the release of
NO by increasing the rate and depth of
breathing.
 Responsible for ‘long term potentiation’-a
type of long term memory.

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PERIPHERAL NERVOUS SYSTEM
In Males: Pelvic
nerve – release NO
- vasodilation and
erection
In Females: NO relaxes
uterine smooth muscles
Thus, risk of premature
birth prevented
Filling of stomach - stretch
receptors stimulated - NO
releasing vagal
parasympathetic neurons
causes adaptive
relaxation.

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4 ROLE ON REPRODUCTIVE SYSTEM:
 The acrosome of sperm releases NO while fusing with egg
which is essential for :
 Blocking the entry of additional sperm, and
 Orienting the pronuclei for fusion.
5 ROLE IN RESPIRATORY SYSTEM:
 NO is being used with other drugs to treat
 Pulmonary Hypertension,
 Heart and Lung Surgery,
 Asthma and Bronchospastic Diseases, and
 Sickle Cell Disease.

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6 ROLE IN RENAL SYSTEM:
 NO increases blood flow through renal glomeruli thus
increasing the rate of filtration.
7 ROLE IN ENDOCRINE SYSTEM:
 NO increases the secretion of endocrine glands.
for example:
8 ROLE IN WOUND HEALING:
 Mediates cell division, maturation and differentiation,
 Mediates angiogenesis i.e. Neovascularization to
nourish the healing tissue.
 Gonadotropin releasing hormone,
 Pancreatic amylase, and
 Adrenaline.

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9 ROLE IN HAIR GROWTH:
 NO cause relaxation of blood vessels of scalp and improves
the blood supply to the scalp and hair follicles thereby
helping your hair to recover its natural thickness.

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1 MUSCULAR EXERCISE: 2 ANTI-OXIDANT FOOD:

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REFERENCES:
(1)Antibacterial Mouthwash Blunts Oral Nitrate Reduction and Increases
blood Pressure in Treated Hypertensive Men and Women.(2014);
bondonno CPLi,
(2) Nitric oxide and cardiovascular effects(1999);
Med 1999;92:164-16,
(3) Nitric oxide: discovery and impact on clinical medicine(1999);
Salvador Moncada FRS FRCP , Nikhil Omer1 Ankur Rohilla1*, Seema,
Rohilla2,
(4) Nitric oxide (NO). Biology.(2006);
Kimball JW,
(5) Nitric oxide and its role in human physiology(2013);
Dr. Rohit bit,
(6) NITRIC Oxide(2014);
Ritu chandal,
(7) Nitric oxide and CVS(2008);
Rk revised 2008,
(8) How arginine helps hair?;
Vosene hair products,
(9) Nitric Oxide II: Therapeutic Uses and Clinical
Applications(2002);
Ayfle BAYSAL,
(10) Interferon gamma and iron metabolism in macrophage
containing salmonella typhimurium:
Nairz M1, Fritsche G, Brunner P, Talasz H, Hantke K, Weiss G,