Eccrine Glands Anatomy and Function

Anatomy

• Eccrine glands are small, coiled tubular glands found in the dermal layer of the skin
• They are distributed all over the body, with the highest density on the palms of the hands and soles of the feet
• Each gland has a secretory coil, a duct, and a myoepithelial cell layer

Function

• Eccrine glands produce a clear, watery sweat that helps to regulate body temperature and maintain hydration
• They play a crucial role in thermoregulation, particularly in hot and humid environments
• Eccrine glands also help to maintain skin health by producing antimicrobial peptides and other defensive molecules

Sweat Production

• Sweat production is stimulated by the sympathetic nervous system, which releases acetylcholine as a neurotransmitter
• Acetylcholine binds to muscarinic receptors on the eccrine glands, triggering sweat production
• Sweat is produced through a process called merocrine secretion, where the gland cells release their contents through exocytosis

Thermoregulation

• Eccrine glands help to regulate body temperature through evaporation of sweat, which cools the body
• Sweat evaporation is an effective cooling mechanism, as it can dissipate heat up to 25 times faster than radiation or convection
• Thermoregulation is critical for maintaining bodily functions, as excessive heat can lead to heatstroke and other heat-related illnesses

Anatomy of Eccrine Glands

• Located in the dermal layer of the skin, eccrine glands are small, coiled tubular glands
• Distributed all over the body, with the highest density found on the palms of the hands and soles of the feet
• Each gland consists of a secretory coil, a duct, and a myoepithelial cell layer

Function and Role in Thermoregulation

• Produce a clear, watery sweat that helps regulate body temperature and maintain hydration
• Crucial in thermoregulation, especially in hot and humid environments
• Help maintain skin health by producing antimicrobial peptides and other defensive molecules

Sweat Production Mechanism

• Stimulated by the sympathetic nervous system, which releases acetylcholine as a neurotransmitter
• Acetylcholine binds to muscarinic receptors on the eccrine glands, triggering sweat production
• Sweat is produced through merocrine secretion, where gland cells release their contents through exocytosis

Importance of Thermoregulation

• Evaporation of sweat cools the body, helping to regulate body temperature
• Sweat evaporation is an effective cooling mechanism, dissipating heat up to 25 times faster than radiation or convection
• Thermoregulation is critical for maintaining bodily functions, as excessive heat can lead to heatstroke and other heat-related illnesses

Apocrine Glands

Sweat Gland Function

• Produce a milky secretion high in protein and lipids
• Regulate body temperature through evaporation of sweat
• Aid in the removal of waste products and toxins
• Play a role in the immune system by producing antimicrobial peptides
• Found primarily in the axillary and anogenital regions

Mammary Gland Structure

• Apocrine glands are also found in the mammary gland
• Consist of a cluster of alveoli (secretory units) surrounded by a network of ducts
• Alveoli are lined with cuboidal epithelial cells that produce milk
• Ducts converge to form a lactiferous duct that opens onto the nipple
• Responsible for the production of milk during lactation

Physiological Responses

• Respond to emotional stimuli, such as stress, anxiety, and sexual arousal
• Physiological responses include:
  • Increased sweat production
  • Increased heart rate and blood pressure
  • Pupillary dilation
• Involved in the "fight or flight" response

Hormonal Regulation

• Regulated by hormones, including:
  • Adrenaline (epinephrine)
  • Cortisol
  • Prolactin
  • Oxytocin
• Hormonal regulation stimulates the production and secretion of sweat and milk
• Modulates the activity of apocrine glands in response to emotional and physiological stimuli