Sweat Gland Volume Research Articles

Sweat gland nerve fiber density and association with sudomotor function, symptoms, and risk factors in adolescents with type 1 diabetes

PurposeTo quantify sweat gland nerve fiber density in adolescents with diabetes. Additionally, to investigate associations between sudomotor innervation, sweat responses, and possible risk factors for sudomotor neuropathy.MethodsCross-sectional study where 60 adolescents with type 1 diabetes (duration > 5 years) and 23 control subjects were included. Clinical data, quantitative sudomotor axon reflex test, and skin biopsies were obtained. Skin tissue was immunostained and imaged by confocal microscopy. Quantification of the sweat gland volume and three-dimensional reconstruction of the nerve fibers was performed using a design-unbiased technique.ResultsAdolescents with diabetes had a significant reduction of maximum and mean values of nerve fiber length and nerve fiber density in sweat glands compared to controls (p values < 0.05). No association between nerve fiber density and sweat responses was found (p = 0.21). In cases with reduced sweat gland nerve fiber length, nerve fiber density, and volume, the sweat response was reduced or absent. Height, systolic blood pressure, time in hypoglycemia, and total daily and basal/total insulin dose were positively correlated to sweat response, while low-density lipoprotein, and HbA1c were negatively correlated with sweat response (p values < 0.05). Other microvascular complications and high cholesterol levels increased the relative risk for reduced sweat gland nerve fiber density.ConclusionOur findings of reduced sweat gland innervation in a selected group of adolescents add new knowledge about the structural changes that occur in autonomic nerves due to diabetes. Evaluating both the sweat gland innervation and sweat gland volume was important for understanding the association with sweat responses. Further research is needed to understand its clinical relevance.

Aging-related shift of eccrine sweat glands toward the skin surface due to tangling and rotation of the secretory ducts revealed by digital 3D skin reconstruction.

BackgroundSweat gland function deteriorates with aging, leading to loss of heat tolerance. However, it is unclear whether and how the structure of sweat glands changes during aging, because the 3D structure is complex and inaccessible.MethodsTo clarify age‐dependent changes in sweat glands, we developed a method for 3D structure analysis of sweat glands by means of X‐ray micro‐CT observation of human skin specimens followed by 3D digital reconstruction on computer (digital 3D skin).ResultsComparison of eccrine sweat glands of abdominal skin from young and old subjects showed that the density and volume of sweat glands do not change with aging. In contrast, the depth of the secretory coil from the skin surface is decreased in the aged group. Surprisingly, the secretory ducts appear tortuous or meandering though their length is unchanged. The secretory coils are located at the dermal‐adipose layer boundary in both groups, but the thickness of the dermal layer decreases with aging, and the depth of the coils is correlated with the dermal thickness.ConclusionOur results suggest that sweat glands twist and rotate with aging to maintain the position of the coil at the dermal‐adipose boundary, causing an overall shift toward the skin surface.

Effects of Brn2 overexpression on eccrine sweat gland development in the mouse paw

Eccrine sweat glands regulate body temperature by secreting water and electrolytes. In humans, eccrine sweat glands are ubiquitous in the skin, except in the lips and external genitalia. In mice, eccrine sweat glands are present only in the paw pad. Brn2 is a protein belonging to a large family of transcription factors. A few studies have examined Brn2 in melanoma cells and epidermal keratinocytes. This study investigated changes in the skin in the K5-Brn2 transgenic mouse, which overexpresses Brn2 and contains the keratin 5 promotor. Interestingly, the volume of eccrine sweat glands was reduced markedly in the K5-Brn2 transgenic mouse compared with the wild-type, while the expression of aquaporin 5, important molecule in sweat secretion, was increased in each sweat gland cell, probably to compensate for the reduction in gland development. However, sweating response to a pilocarpine injection in the hind paw was significantly decreased in the K5-Brn2 transgenic mouse compared with the wild-type. The paw epidermis was thicker in the K5-Brn2 transgenic mouse compared with the wild-type. Taken together, eccrine sweat gland development and sweat secretion were suppressed markedly in the K5-Brn2 transgenic mouse. These results may be associated with dominant development of the epidermis by Brn2 overexpression in the paw skin.

Quantification of sweat gland volume and innervation in neuropathy: Correlation with thermoregulatory sweat testing

No study has correlated thermoregulatory sweat testing (TST) with histopathologic study of sweat glands (SGs) and SG nerve fibers (SGNFs). We studied 10 neuropathy patients in whom anhidrosis was found by TST and 10 matched controls. Skin biopsies were taken from both anhidrotic and sweating skin and immunohistochemical staining was done for nerves and basement membrane. For each biopsy, total tissue volume, total SG volume, and total SGNF length were measured. SGNF length per biopsy volume, SG volume per biopsy volume (SG%), and SGNF length per SG volume were calculated. SGNF length per biopsy volume was reduced in anhidrotic site biopsies of patients compared with controls. SG% was decreased and SGNF length per SG volume increased in patients compared with controls. The results suggest a concomitant loss of SG volume and SGNF length in neuropathy, with greater loss of SGNFs in anhidrotic skin, possibly exceeding collateral reinnervation.

Differences of skin morphology in Bos indicus, Bos taurus, and their crossbreds

Cutaneous evaporation is the main avenue by which cattle dissipate heat via the involvement of sweat glands and other skin components. The difference in skin morphology between B. indicus and B. taurus has been recognized, as well as differences in their ability to tolerate heat. The objective of this study was to compare skin morphology between B. indicus, B. taurus, and their crossbreds. Skin samples of Sahiwal (B. indicus) (n=10, reddish brown skin) and Holstein Friesian (HF) (B. taurus) (n=10, black and white skin) and crossbred of HF75% (n=10, black and white skin) and HF87.5 % (n=10, black and white skin) were biopsied for histological study, followed by measurement of skin components. The results indicated that breed significantly affected sweat gland morphology. The shape of the sweat gland, as indicated by the ratio of length/diameter, in Sahiwal was baggier in shape compared to HF (5.99 and 9.52) while values for crossbreds were intermediate (7.82, 8.45). The density and volume of sweat glands in Sahiwal (1,058 glands/cm(2); 1.60 μ(3) × 10(-6)) were higher than in HF (920 glands/cm(2); 0.51 μ(3)x10(-6)) and crossbreds, both HF 75 % (709 glands/cm(2); 0.68 μ(3) × 10(-6)) and HF 87.5 % (691 glands/cm(2); 0.61 μ(3) × 10(-6)) respectively. However, capillary surface area was greater for HF (2.07 cm(2)) compared to Sahiwal (1.79 cm(2)); accordingly, the lower genetic fraction of HF in crossbred cattle showed less capillary surface area (1.83 and 1.9 cm(2) for HF75% and HF87.5 %) (P<0.01). Nerve density was not significantly different between Sahiwal and HF but was higher in the crossbred (P<0.01) cattle. Moreover, the effect of skin color (black and white) was evaluated and it was found that there was an interaction (P<0.01) between breed and skin color on the skin components. This study reveals that there are differences in skin morphology among B. indicus, B. taurus and their crossbreds, with these differences being more or less related to the genetic fraction of HF. This may imply that capability for cutaneous evaporative heat loss and tolerance to heat in crossbred cattle could be related to skin morphology.

Sweat glands of the scrotum of the bull.

Skin samples were taken post mortem from the scrotum, abdomen and neck of 4 mature bulls. The volume of sweat glands per unit skin surface area of the scrotum was greater than that of other body regions. Within the scrotum there was a gradient in sweat gland volume increasing from proximal through to distal parts of the scrotum. These results suggest a previously unidentified variable cooling capacity of the scrotum depending on testicular descent.

Effect of oestradiol-17 beta on perineal and neck skin glands in heifer calves.

Ten 16-week-old Friesian x Hereford heifer calves were split into experimental and control groups. Experimental animals were given an implant of oestradiol-17 beta in the ear whilst controls were given blank implants. They were killed 14 days later. After implantation the experimental group had consistently greater (P less than 0.01) plasma concentrations of oestradiol-17 beta than the control group. After death, sebaceous gland volume in the perineal region was greater (P less than 0.01) in the experimental than in the control group, whereas sebaceous gland volume in the neck was smaller (P less than 0.01). Sweat gland volume in the perineal region was greater (P less than 0.01) in the experimental than in the control group. There was no difference between groups in the volume of sweat glands in the neck.

Studies on the nature of sweat gland 'fatigue' in the goat.

1. The nature of the ;fatigue' of sweating that occurs in the goat upon exposure to environmental conditions of 40 degrees C/26 degrees C (dry bulb/wet bulb) has been examined.2. Heat exposure activated all the sweat glands and the decrement in sweating which occurred was due to a decline in the amount of sweat produced by each gland.3. The decline in sweating activity was associated with a decrease in sweat gland volume and a thickening of the glandular wall. The restoration of sweat gland function took approximately 5-6 hr after removing the animal from the hot environment but the restoration of sweat gland volume took longer.4. The volume of sweat produced was greater than the decrease in sweat gland volume and it is concluded that ;fatigue' is due to the rate of expulsion exceeding the rate of sweat production.5. Repeated intravenous injections of adrenaline at 40 degrees C resulted in a decline in sweat output and reduced the normal glandular response to heat exposure.

SOME SKIN CHARACTERISTICS OF "SNORTER" DWARFISM IN THE BOVINE

Four characteristics, namely, skin thickness, the number of sweat glands per square centimeter of skin, the volume of sweat glands and the depth at which these sweat glands were located were investigated in the three genotypes of Hereford cattle.Of the four characteristics studied, only skin thickness differed significantly among the three genotypes. The dwarfs had the thinnest skin and the normal animals had the thickest skin. The heterozygotes showed intermediate values. No significant differences were revealed among the three genotypes for the other three characteristics.

Sweating rate at different body regions in cattle and its correlation with some quantitative components of sweat gland volume for a given area of skin

Sweating rates at five body regions on four Jersey and four Sahiwal x Jersey crossbred heifers were measured in a hot room under three treatments differing in temperature and duration. The correlations between sweating rate and some quantitative components of sweat gland volume for a given area of skin were examined. Differences in sweating rate between body regions, interactions between breed and body region in sweating rate, and differences in sweating rate for the various treatments were all shown to be statistically significant. There was no significant interaction between body regions and treatment in sweating rate.Between body regions within an animal, there was a positive correlation between sweat gland population density and sweating rate and a negative correlation between mean sweat gland volume and sweating rate. This negative correlation was associated with the fact that regions with high sweat gland population density also tended to have smaller sweat glands and vice versa. Indications of a positive correlation between the total sweat gland volume per unit area and sweating rate were also found, though none of these approached statistical significance.

Consumption of Oxygen by Sweat Glands of Indian Zebu Cattle

OXYGEN consumption of skin slices is correlated with the volume of sweat glands and is increased after injection of pilocarpine1,2. The metabolism of glucose and glycolysis has been studied in the skin slices3,4. There is a greater evaporation of sweat from the hump of the Indian zebu cattle5,6.

Some skin characters in five breeds of European (Bos taurus) dairy cattle

Observations were made of a number of skin characters in five breeds of European (Bos taurus L.) dairy cattle. Skin samples were taken from the cattle in January and July. There were differences between breeds in sweat gland volume and length! diameter ratio, in skin and papillary layer thickness, in the ratio skin thickness/papillary layer thickness, and in the degree of shrinkage in transverse sections cut from the papillary layer. There were no differences between breeds in density of follicle population (and hence sweat glands) per unit area of skin. Sweat gland volume, skin thickness, and papillary layer thickness were larger in winter than in summer, but there were no such differences for sweat gland length/ diameter ratio, the ratio skin thickness/papillary layer thickness, and follicle population density. The only significant overall correlations between characters were those between sweat gland volume and sweat gland length/diameter ratio, and sweat gland volume and papillary layer depth.

The effect of feeding on evaporative heat loss and body temperature in Zebu and Jersey heifers

Some physiological responses to moderate (70–80°F dry bulb and 60–70° wet bulb) ante-room and high (103° dry bulb and 83° wet bulb) hot room temperatures by two Jersey and two Zebu heifers under alternate conditions of normal feed intake and fasting are reported. At moderate temperatures both breeds exhibited a diurnal rhythm in feed and water consumption and in skin temperature, sweating rate, rectal temperature, and respiration rate. In the case of skin temperature, sweating rate, and respiration rate this diurnal rhythm disappeared in the hot room. In the hot room, water consumption increased for all animals. Feed intake was depressed in Jerseys but not in Zebus. In the ante-room, animals tended to have higher sweating rates and rectal temperatures when fed than when not fed. Fed animals did not have uniformly greater skin temperatures in the hot room, but sweating rates, rectal temperatures, and respiration rates were greater. Jerseys had greater sweating rates and lower rectal temperatures than Zebus at ante-room temperatures, but Zebus had greater sweating rates and lower rectal temperatures in the hot room. When fed, Jerseys failed to control their temperatures in the hot room, despite large increases in sweating and respiration rates and a reduction in appetite; whereas Zebus maintained their appetites, and slightly reduced rectal temperatures, by means of their greatly increased sweating rate and a slight increase in respiration rate. Differences between Jerseys and Zebus in sweat gland volume were of the order previously reported for these breeds, and differences in population density were in accordance with differences in body size. The Jersey having the smallest sweat glands also had the lowest number per unit area, and sweated less than its Jersey mate.

Quantitative and morphological variation of sweat glands, skin thickness, and skin shrinkage over various body regions of Sahiwal Zebu and Jersey cattle

By comparison with Jerseys the sweat glands of Sahiwals were 70% longer, 55% wider, and 315% greater in mean volume. Total sweat gland volume per unit area of skin was 340%, greater and skin thickness was 60% greater, but skin shrinkage was 30%, less. The density of sweat glands was 1130/cm2 for Jerseys and 1200/cm2 for Sahiwals. In almost all animals the characters varied significantly between the various body positions, and in most cases showed trends. Values for the generally adopted midside sampling position were usually within 10% of the mean value for all positions. Sweat gland shape varied over the body. Most of the shapes observed in the two species were present in one position or another within each animal.

Sweat glands in Zebu (Bos indicus L.) and European (B. taurus L.) cattle. II. Effects of season and exercise on sweat gland volume

Seasonal variation in sweat gland volume is reported in two breeds of Zebu dairy cattle. Changes which occurred in the volume of sweat glands in Jersey and in Zebu x Jersey cattle, as the result of sweating induced by exercise, are described. The crossbred cattle, which had larger sweat glands than the Jerseys, sweated at a greater rate, and had a smaller rise in rectal temperature, which returned more rapidly to normal. It is suggested that there is a relationship between sweat gland volume and activity, and that the seasonal changes in volume observed in the two Zebu breeds are largely due to changes in ambient temperature.