Eccrine Merocrine Sweat Glands

Eccrine Merocrine Sweat Glands: The Body's Cooling System

Eccrine merocrine sweat glands are the most numerous type of sweat gland found in humans. Unlike apocrine glands, which are associated with body odor, eccrine glands play a crucial role in thermoregulation, maintaining our body temperature within a safe and functional range. Understanding their structure, function, and regulation is vital to understanding human physiology and various health conditions. This article will provide a comprehensive overview of these essential glands.

I. Structure and Location

Eccrine sweat glands are simple, coiled tubular glands. They are situated deep within the dermis, the second layer of skin, and extend upwards to open directly onto the skin's surface via a sweat pore. The secretory portion of the gland, the coiled tube, is responsible for producing sweat. This portion is composed of two cell types: clear cells and dark cells. Clear cells are responsible for the majority of sweat production, primarily water and electrolytes. Dark cells, on the other hand, are believed to secrete glycoproteins and other organic molecules. The duct, which carries the sweat from the secretory portion to the skin's surface, is lined with stratified cuboidal epithelium, which helps in modifying the sweat composition before secretion. Eccrine glands are distributed almost ubiquitously across the body surface, but their density varies significantly depending on the location. Areas like the palms of the hands, soles of the feet, and forehead have a much higher concentration of eccrine glands than other parts of the body, reflecting their crucial role in thermoregulation in these areas.

II. Sweat Composition and Function

Eccrine sweat is primarily composed of water (99%), with small amounts of electrolytes (sodium, chloride, potassium), urea, lactic acid, and ammonia. The precise composition can vary depending on factors such as hydration status, environmental temperature, and activity level. The primary function of eccrine sweat is thermoregulation. When the body's core temperature rises, the hypothalamus, the body's thermostat, signals the eccrine glands to produce and release sweat. As the sweat evaporates from the skin's surface, it absorbs heat, thus cooling the body. This process is particularly crucial during physical activity and in hot environments. Besides thermoregulation, eccrine sweat also plays a minor role in excretion, removing small amounts of metabolic waste products from the body.

III. Regulation of Eccrine Sweat Gland Activity

The activity of eccrine sweat glands is under the control of the sympathetic nervous system, although it is not under voluntary control like skeletal muscles. The sympathetic nervous system uses acetylcholine, a neurotransmitter, to stimulate the sweat glands. This cholinergic sweating is distinct from adrenergic sweating, which involves the release of norepinephrine and is typically associated with emotional sweating or sweating related to stress. Several factors influence eccrine sweat gland activity including:

Core body temperature: Increased body temperature directly stimulates sweating.
Environmental temperature and humidity: High temperature and humidity reduce the effectiveness of evaporative cooling, leading to increased sweating.
Physical activity: Exercise elevates body temperature, triggering increased sweat production.
Hormonal influences: Some hormones can influence sweat gland activity, although the effects are generally less significant than the neural control.
Emotional state: Stress and anxiety can stimulate sweating, though this is often mediated by different parts of the nervous system than thermoregulatory sweating.

IV. Clinical Significance

Disorders affecting eccrine sweat glands can lead to a range of symptoms. For instance, excessive sweating (hyperhidrosis) can be caused by several factors, including genetic predisposition, neurological disorders, and certain medications. On the other hand, insufficient sweating (hypohidrosis) can be a symptom of dehydration, skin disorders, or nerve damage. Understanding the function and regulation of eccrine sweat glands is crucial for diagnosing and managing these conditions. Anhidrosis, the complete absence of sweat, is a serious condition that can lead to heat stroke and requires immediate medical attention. Furthermore, the composition of eccrine sweat can be used to diagnose certain metabolic disorders, such as cystic fibrosis.

V. Summary

Eccrine merocrine sweat glands are vital components of the human integumentary system, primarily responsible for thermoregulation through the production and secretion of sweat. Their structure, function, and regulation are complex processes involving the interplay of neural and hormonal signals, as well as environmental factors. Understanding these glands is crucial for comprehending various physiological processes and recognizing disorders related to sweating.

FAQs

1. What is the difference between eccrine and apocrine sweat glands? Eccrine glands are responsible for thermoregulation and secrete a watery sweat, while apocrine glands are associated with body odor and secrete a thicker, oily sweat that is released into hair follicles.

2. Why do my palms sweat when I’m nervous? This is due to the sympathetic nervous system’s response to stress. While primarily controlled by the cholinergic system, stress-induced sweating can involve both cholinergic and adrenergic pathways.

3. Can you stop sweating completely? While you can't completely stop sweating, certain antiperspirants can reduce sweat production by temporarily blocking sweat ducts. However, complete cessation of sweating can be dangerous due to impaired thermoregulation.

4. What are the symptoms of hyperhidrosis? Symptoms of hyperhidrosis include excessive sweating in specific areas (hands, feet, armpits) and can interfere with daily activities. This often necessitates medical intervention.

5. How does dehydration affect eccrine sweat gland function? Dehydration reduces the amount of water available for sweat production, making thermoregulation less effective and increasing the risk of heat stroke.

Search Results:

Sweat Gland Function - an overview | ScienceDirect Topics Eccrine sweat glands are capable of producing large amounts of sweat as evidenced by the microvilli (IC) line the intercellular channels and the appearance of apical and basal elaborations of the cell membranes.

Sweat Glands: Eccrine and Apocrine | SpringerLink The terms “eccrine” and “apocrine” [Kϱίνειν, to separate (secrete); έϰ, out of; ά;πo from] were introduced by S Chiefferdecker (1917) to describe two types of simple tubular exocrine gland within the merocrine category.

Eccrine sweat gland development and sweat secretion Derived from embryonic ectoderm, millions of eccrine glands are distributed across human skin and secrete litres of sweat per day. Their easy accessibility has facilitated the start of analyses of their development and function.

Eccrine sweat gland - Wikipedia Eccrine sweat glands are found in virtually all skin, with the highest density in the palms of the hands, and soles of the feet, and on the head, but much less on the torso and the extremities. In other mammals, they are relatively sparse, being found …

The human eccrine sweat gland: Structure, function and disorders Disorders of sweat glands and the resultant conditions, most often relate to defects in the secretion of sweat and its release on to the skin surface. This review concentrates on the processes that enable the production of human sweat.

Regional variations in transepidermal water loss, eccrine sweat gland ... Some 20–30 years later, the merocrine classification was subdivided into apocrine and eccrine sweat glands [25, 26], with Sato et al. [1] eventually adding a third class; the apoeccrine glands. For this review, the primary focus is upon the eccrine glands.

Skin Glands: Sebaceous, Eccrine, and Apocrine Glands Sebaceous glands are holocrine glands, and sweat glands (both eccrine and apocrine ones) are merocrine glands. Sebaceous glands are multilobular structures that consist of acini connected to a common excretory duct and are usually associated with a hair follicle.

Anatomy, Skin Sweat Glands - PubMed 10 Oct 2022 · Sweat glands are appendages of the integument. There are eccrine and apocrine sweat glands. They differ in embryology, distribution, and function. Eccrine sweat glands are simple, coiled, tubular glands present throughout the …

Skin: The Histology Guide The sweat glands are simple tubular exocrine glands that are found in the superficial hypodermis bordering on the dermis. They discharge their contents onto the surface of the skin via coiled secretory ducts (see the diagram opposite).

Eccrine sweat gland development and sweat secretion - PMC Eccrine sweat glands help to maintain homoeostasis, primarily by stabilizing body temperature. Derived from embryonic ectoderm, millions of eccrine glands are distributed across human skin and secrete litres of sweat per day.

Eccrine sweat glands - wikidoc Eccrine sweat glands (sometimes merocrine sweat glands) are coiled tubular glands derived from the outer layer of skin but extending into the inner layer used for body temperature regulation.

Sweat glands: Structure and function | Kenhub 3 Nov 2023 · There are two types of sweat glands: Eccrine glands are found all over the body and secrete a watery product that cools the skin. Apocrine sweat glands are mainly found in the armpits and perianal area, and secrete a more viscous, odorous product.

The Science of How and Why We Sweat: 6 Fast Facts 4 Apr 2025 · There are two primary types of sweat glands in the body, Eccrine glands and Apocrine glands. The most prevalent gland is the eccrine gland. Humans have roughly 2-4 million eccrine glands that are found almost everywhere on the body and respond to both thermal and emotion stimuli.

Neurobiology of Skin Appendages: Eccrine, Apocrine, and Apoeccrine ... Eccrine sweat glands express various muscarinic acetylcholine receptor subtypes and eccrine sweat secretion can be blocked effectively by anti-muscarinic substances.

Eccrine Sweat Gland | Complete Anatomy - Elsevier An eccrine gland is an ordinary, or simple, sweat gland; they are sweat glands of the merocrine type—unbranched, coiled, tubular glands that are distributed over almost all of the body surface and promote cooling by evaporation of their secretion (Dorland, 2011).

Glands: Anatomy & Function - Cleveland Clinic 1 Apr 2025 · Ovaries in females Pituitary and pineal glands in your brain Prostate, seminal glands (also known as seminal vesicles) and accessory glands in males Salivary glands like the parotid gland in your mouth Sebaceous glands in your hair follicles Skene’s gland near the vagina Sweat glands (apocrine and eccrine) in your skin Thymus gland inside ...

Glands – Classification, Structure, Functions, Examples 1 Apr 2025 · Exocrine glands have functions in digestion, thermoregulation, and protection as their highly defined duct networks transport their secretions—such as enzymes, mucus, and sweat—to certain target sites.

Physiology of sweat gland function: The roles of sweating and sweat ... Apoeccrine glands develop from eccrine sweat glands between the ages of ~8 to 14 years and increase to as high as 45% of the total axillary glands by age 16–18 [23].

Understanding Eccrine Sweat Glands - HowStuffWorks From breaking into a nervous sweat in public situations to harboring a more serious condition, seemingly simple eccrine sweat glands represent millions of opportunities for health concerns.

Eccrine Sweat Glands - medcell.org Eccrine sweat glands localize to the dermis and upper region of the hypodermis. The secretory gland is coiled and consists of of secretory, epithelial cells and an outer layer of myoepithelial cells that are contractile. The secretory cells are a mix of light and dark staining cells.

Anatomy, Skin, Sudoriferous Gland - StatPearls - NCBI Bookshelf 24 Apr 2023 · Eccrine sweat glands allow for temperature control. When body temperature rises during physical activity, increased ambient temperature, or fever, these glands respond by secreting sweat. This sweat is eventually evaporated from the surface of the skin, effectively cooling down body temperature.

Anatomy, Skin Sweat Glands - StatPearls - NCBI Bookshelf 10 Oct 2022 · Sweat glands are appendages of the integument. There are eccrine and apocrine sweat glands. They differ in embryology, distribution, and function. Eccrine sweat glands are simple, coiled, tubular glands present throughout the …

Sweat gland - Structure, Location, Function, Anatomy, Diagram 21 Jan 2025 · A sweat gland is a specialized exocrine gland in the skin that produces and secretes sweat, primarily composed of water, salts, and waste products. Sweat glands are essential for regulating body temperature and excreting metabolic waste.

Eccrine Merocrine Sweat Glands