A descript about Eccrine Glands

1. ECCRINE GLANDS

2. OVERVIEW
• Major Sweat Glands
• Primates
• ‘Atrichial’
• Temp Regulation
• Grip
• Minor Excretory

3. ETYMOLOGY
Merocrine (Gk: Meros – Part + Krinien – Separate)
Sudoriferous (Lat: Sudare – Sweat Fer – to carry /
bear)
Eccrine (Gk : Ekkrinien – to secrete)
Exocrine Glands

4. DENSITY / DISTRIBUTION
• Generalized distt INCL Glans / Prepuce
EXCL Vermillion Border Lip
Nail Bed
Clitoris / Labia Minora
Ext Aud Canal
02 – 04 Million Glands / BSA
30 – 40 mcg Indl Weight (Cum – 100 g)
Males > Females > Pre-pubertal Distt

5. DISTRIBUTION (Glands/cm2)
• Volar 600 – 700
• Forehead 181
• Forearm 108
• Back 64

6. EMBRYOLOGY
• Epidermal downgrowths in Fetal Life
(Ectodermal Origin)
• 03 Months – Palms / Soles
• 05 Months – Other Areas
• 08 Months - Adult Morphology
No Post-natal development

7. DEVELOPMENT

8. STRUCTURE
• SIMPLE COILED TUBULAR Glands
• Spiral Intraepidermal duct (ACROSYRINGIUM)
• Straight Intradermal duct UPPER DERMIS
• Coiled Terminal Portion (ACINUS / FUNDUS)
2/3rd SECRETORY
1/3rd DUCTAL

10. SECRETORY COIL
• 02-05 mm Uncoiled Length ; 60-80 microns Dia
Large CLEAR CELLS (CC)
Secretory / Pyramidal / Rest on ME
Lipofuschin Autofluoroscent Granules
Aqueous Substance + Glycogen
House Na+ - PUMP for Active Ion Tpt

11. SECRETORY COIL
• Small DARK Cells (DC)
Mucoid / Cuboidal / Rest on CC
PAS – positive Glycoproteins
Sialomucin secretion
• Myo-Epithelial Cells (ME)
Spindle / Rest on BM / Support CC
Myofilaments / Mechanical Support
? Propel Sweat to the surface
Non-Secretory
COLLAGEN-RICH HYALINE BASEMENT MEMBRANE

12. ULTRASTRUCTURE OF
SECRETORY COIL

14. INTRADERMAL SWEAT DUCT
• LUMINAL Cells – Inner / Small / Cuboidal /
Basophilic
• DUCTAL Cells – Outer (Basal) / Na – K –
ATPase Activity ? Ductal Reabsorption of
Sweat
Tonofilament – rich Pseudo-Cuticle Rigidity

15. ACROSYRINGIUM
• Intraepidermal Ductal System
• Rete Ridge  Corneal Surface
• Single layer of Inner Luminal Cells
• 02-03 Layers of Outer Basal Cells
Cells contain Desmosomes, few Melanocytes and
undergo Kertainization
Final Propulsion of Formed Sweat to Surface via
Pore

16. FUNCTIONS
• SWEATING
Heat Stress – Evaporative Heat Loss
(1 L  585 kCal)
Emotional Stimuli
Gustatory Stimuli
• MOISTURIZING
For Improved Grip
• EXCRETION
Minor / Adjunct Organ
except Certain Drugs
MAINTAIN ELECTROLYTE-BALANCE
ANTI-MICROBIAL PEPTIDES (DERMICIDIN - ‘Sweat Antibiotic’)

17. CONTROL OF ECCRINE SWEATING
03 PHYSIOLOGICAL STIMULI
THERMOREGULATORY (Hypothalamus)
EMOTIONAL (?Frontal)
GUSTATORY (Medulla)

18. THERMOREGULATORY MECHANISM

19. INNERVATION OF ECCRINE GLANDS
• Via Efferent Sudomotor Pathway through Postganglionic
non-myelinated C fibres to Eccrine Glands
• SKIN SUPPLY
UPPER LIMB T2 – T8
TRUNK T4 – T12
LOWER LIMB L2 – L4
• Sympathetic nerve supply - MUSCARINIC & CHOLINERGIC R
• Alpha / Beta Adrenergic Receptors

20. SUDOMOTOR PATHWAY

21. THERMOREGULATION
• HEAT LOSS - radiation,
convection, conduction and
evaporation
• Thermal Sweating keeps Body
Temperature constant
• High environmental Temp 
Evaporational Heat Loss
provides maximum regulation

22. THERMOREGULATION
FACTORS :
LOCAL SKIN TEMP
10 deg C Rise  3X Local Sweating
CORE TEMP
Similar Rise  9X Local Skin Temp

23. SWEATING
• CLEAR ODOURLESS ECCRINE SECRETION 
PERSPIRATION
• Comprises WATER + electrolytes
• SWEAT RATE
No of Active Sweat Glands per area X Rate of
Sweating / Gland (Max 02-20 micro L / gland)
• 10 L SWEAT / DAY in Acclimatized indl

24. CONTENTS
• pH : 4.3 – 4.7
• WATER
• Inorganic ions – sodium, chloride, potassium
• Lactate / Urea (Moisturizers)
• Glucose +/-
• Ammonia and amino acids
• Proteins including proteases

25. MECHANISM OF SWEAT PRODUCTION
• 02 STEPS :
(1) SECRETORY COIL  ‘ULTRAFILTRATE’
ISOTONIC FLUID i/r/o Ach
(2) DUCTAL SYSTEM  REABSORBS NaCl  HYPOTONIC
SURFACE SWEAT

26. • ACh stimulates EG by inc intracellular Ca2+
• Opens K+ Cl- Channels in CC  Loss of K+
Cl- H20
• Eccrine Gland Shrinkage
• Na K ATPase Pump Activated to facilitate
Intracellular entry of Na+ K+ Cl-
• Isotonic NaCl in Lumen of Coiled Tubule

27. DUCTAL REABSORPTION
• Na+ Re-Entry via Na+ Channels
and Transport across BDC by
Na+ K+ ATPase Pump
• SWEAT ACIDIFICATION by
Carbonic Anhydrase

28. OTHER FACTORS AFFECTING
SWEATING
• Environmental conditions(Ambient Temp / Air Velocity
• Clothing (Insulation and Moisture Permeability)
• Degree of Acclimatization
• Physical activity level
• Emotional stress

29. EXCRETORY FUNCTION
• MINOR ROUTE for Water / Electrolytes /
Metabolic Wastes
• ACTIVE EXCRETION of DRUGS :
– Griseofulvin / Ketoconazole / ?Fluconazole
– Ciprofloxacin / Sulpha Drugs
– Phenobarbitol / Other AEDs
– ?? Chemotherapeutic Agents / DMARDs ??

30. ECCRINE GLAND
DISORDERS

37. THANK YOU