A presentation on cutaneous vasculature and thermoregulation.

1. CUTANEOUS
VASCULATURE
AndThermoregulation
14.08.20
Dr. Jerriton
Final Yr PG

2. Development
Architecture
Ultrastructure
Functions
Diseases
OVERVIEW

3. INTRODUCTION
• The skin blood flow is normally 250 to 300 mL/min but can vary
from nearly zero in cold to as much as 6 to 8 L/min.
• The skin vascular system is unique in that it is organized into 3
functionally distinct vascular segments: the loops within the tips
of the papillae, the SVP, and the DVP.
• It serves several functions other than blood supply.
• It is implicated in several skin diseases.

4. 1. DEVELOPMENT

7. ANGIOGENESIS

10. ANGIOGENESIS
CONTROL

12. 2. ARCHITECTURE

18. A single vascular loop extends
into the dermal papilla of the
hair follicle, while a mesh of
blood vessels surrounds the
anagen hair follicle (CD31 IHC
stain)

19. 3. ULTRASTRUCTURE

23. WEIBEL PALADE BODIES
• ET cell specific elongated rod-shaped storage
granules in the cytoplasm
• Released by exocytosis in response to vascular
perturbation
• Role in inflammation, hemostasis, regulation of
vascular tone and angiogenesis

24. CONTENTS OF WPB

25. 4. FUNCTIONS

26. Thermoregulation
Hemostasis
Permselectivity
Perfusion
Immune surveillance
4.
FUNCTIONS

27. THERMOREGULATION
• Thermoregulation is the ability of an organism to maintain a core
body temperature, which is 37° C (98°F) within an optimal
physiological range.
• Thermoneutral zone (TNZ) is the range of ambient temperatures
where the body can maintain its core temperature solely through
regulating dry heat loss, i.e., skin blood flow
• TNZ for a naked resting human = 26°C to 36°C

29. THERMOREGULATION
Non-Glabrous Skin Glabrous Skin
Reflex thermoregulation by the
sympathetic nervous system
Cold Hot
Sympathetic system
Vasoconstriction
Para-sympathetic system
+ Neurotransmitter release
Vasodilatation

30. THERMOREGULATION
Non-Glabrous Skin Glabrous Skin
Reflex thermoregulation by the
sympathetic nervous system
Cold Hot
Sympathetic system
Vasoconstriction
Para-sympathetic system
+ Neurotransmitter release
Vasodilatation
AV anastomoses
(Glomus body)

31. THERMOREGULATION
Non-Glabrous Skin Glabrous Skin
Reflex thermoregulation by the
sympathetic nervous system
Cold Hot
Sympathetic system
Vasoconstriction
Para-sympathetic system
+ Neurotransmitter release
Vasodilatation
AV anastomoses
(Glomus body)
Cold Hot

32. THERMOREGULATION

33. 5. DISEASES

34. POST-MENOPAUSAL HOT FLUSH
• Disorder of thermoregulation
• Rapid and exaggerated heat dissipation response
• Triggered by small elevations in core body temperature (d/t
estrogen depletion) acting within a greatly reduced
thermoneutral zone
• Estrogen replacement acts by reducing core body temperature

35. RAYNAUD’S DISEASE
• Pathological thermoregulatory reflex
• Exaggerated vasospastic response to cold or emotion
• Increased sympathetic vasoconstrictive activity, which results in
increased blood flow through AV anastomosis

36. REFERENCES
1. Rook’s Textbook of Dermatology
2. Fitzpatrick’s Dermatology
3. Bolognia’s Dermatology