scholarly journals Comparative evidence for the independent evolution of hair and sweat gland traits in primates

2018 ◽  
Author(s):  
Yana G. Kamberov ◽  
Samantha M. Guhan ◽  
Alessandra DeMarchis ◽  
Judy Jiang ◽  
Sara Sherwood Wright ◽  
...  
Keyword(s):  
Sweat Gland ◽  
Hair Follicles ◽  
Sweat Glands ◽  
Eccrine Gland ◽  
Hair Density ◽  
External Appearance ◽  
Human Feature ◽  
Close Relatives ◽  
Eccrine Sweat Glands ◽  
Eccrine Sweat

AbstractHumans differ in many respects from other primates, but perhaps no derived human feature is more striking than our naked skin. Long purported to be adaptive, humans’ unique external appearance is characterized by changes in both the patterning of hair follicles and eccrine sweat glands, producing decreased hair cover and increased sweat gland density. Despite the conspicuousness of these features and their potential evolutionary importance, there is a lack of clarity regarding how they evolved within the primate lineage. We thus collected and quantified the density of hair follicles and eccrine sweat glands from five regions of the skin in three species of primates: macaque, chimpanzee and human. Although human hair cover is greatly attenuated relative to that of our close relatives, we find that humans have a chimpanzee-like hair density that is significantly lower than that of macaques. In contrast, eccrine gland density is on average 10-fold higher in humans compared to chimpanzees and macaques, whose density is strikingly similar. Our findings suggest that a decrease in hair density in the ancestors of humans and apes was followed by an increase in eccrine gland density and a reduction in fur cover in humans. This work answers longstanding questions about the traits that make human skin unique and substantiates a model in which the evolution of expanded eccrine gland density was exclusive to the human lineage.

Differential antigen expression between human eccrine sweat glands and hair follicles/pilosebaceous units

2019 ◽  
Vol 50 (4) ◽  
pp. 335-342 ◽  
Author(s):  
Leilei Cao ◽  
Liyun Chen ◽  
Haihong Li ◽  
Zairong Wei ◽  
Sitian Xie ◽  
...  
Keyword(s):  
Antigen Expression ◽  
Hair Follicles ◽  
Sweat Glands ◽  
Eccrine Sweat Glands ◽  
Eccrine Sweat

Pathologic S-phase in the cells of eccrine sweat glands and of hair follicles in psoriasis

1980 ◽  
Vol 268 (3) ◽  
pp. 257-260 ◽  
Author(s):  
Attila Galosi ◽  
Helmut Pullmann ◽  
Gerd Klaus Steigleder
Keyword(s):  
Hair Follicles ◽  
S Phase ◽  
Sweat Glands ◽  
Eccrine Sweat Glands ◽  
Eccrine Sweat

scholarly journals A genetic basis of variation in eccrine sweat gland and hair follicle density

2015 ◽  
Vol 112 (32) ◽  
pp. 9932-9937 ◽  
Author(s):  
Yana G. Kamberov ◽  
Elinor K. Karlsson ◽  
Gerda L. Kamberova ◽  
Daniel E. Lieberman ◽  
Pardis C. Sabeti ◽  
...  
Keyword(s):  
Hair Follicle ◽  
Genetic Regulation ◽  
Eccrine Sweat Gland ◽  
Hair Follicles ◽  
The Body ◽  
Chromosome 1 ◽  
Sweat Glands ◽  
Eccrine Gland ◽  
Eccrine Glands ◽  
Eccrine Sweat

Among the unique features of humans, one of the most salient is the ability to effectively cool the body during extreme prolonged activity through the evapotranspiration of water on the skin’s surface. The evolution of this novel physiological ability required a dramatic increase in the density and distribution of eccrine sweat glands relative to other mammals and a concomitant reduction of body hair cover. Elucidation of the genetic underpinnings for these adaptive changes is confounded by a lack of knowledge about how eccrine gland fate and density are specified during development. Moreover, although reciprocal changes in hair cover and eccrine gland density are required for efficient thermoregulation, it is unclear if these changes are linked by a common genetic regulation. To identify pathways controlling the relative patterning of eccrine glands and hair follicles, we exploited natural variation in the density of these organs between different strains of mice. Quantitative trait locus mapping identified a large region on mouse Chromosome 1 that controls both hair and eccrine gland densities. Differential and allelic expression analysis of the genes within this interval coupled with subsequent functional studies demonstrated that the level of En1 activity directs the relative numbers of eccrine glands and hair follicles. These findings implicate En1 as a newly identified and reciprocal determinant of hair follicle and eccrine gland density and identify a pathway that could have contributed to the evolution of the unique features of human skin.

scholarly journals Malignant Eccrine Spiradenoma of the External Auditory Canal: A Case Report and Literature Review

2021 ◽  
Vol 10 ◽  
Author(s):  
Dong You ◽  
Zhao Ma ◽  
Jing Liu ◽  
Xiao Song ◽  
Wei Dong
Keyword(s):  
Case Report ◽  
Literature Review ◽  
External Auditory Canal ◽  
Sweat Gland ◽  
Sweat Glands ◽  
Gland Tumor ◽  
Sweat Gland Tumor ◽  
Eccrine Sweat Glands ◽  
Eccrine Sweat

Spiradenocarcinoma, or malignant eccrine spiradenoma (MES), is a rare sweat gland tumor originating from eccrine sweat glands. To the best of our knowledge, only two cases of MES of the external auditory canal have been reported to date. Here, we report a third case of MES located in the external auditory canal.

Pharmacological Responsiveness of Sweat Glands in Anxious Patients and Healthy Volunteers

1982 ◽  
Vol 141 (2) ◽  
pp. 154-161 ◽  
Author(s):  
Shani Maple ◽  
C. M. Bradshaw ◽  
E. Szabadi
Keyword(s):  
Healthy Volunteers ◽  
Dose Response ◽  
Sweat Gland ◽  
Sweat Glands ◽  
Response Curves ◽  
Anxiety Neurosis ◽  
Female Patients ◽  
Dose Response Curves ◽  
Eccrine Sweat Glands ◽  
Eccrine Sweat

SummaryThe responsiveness of eccrine sweat glands to local intradermal injections of carbachol and phenylephrine was studied in six male and six female healthy volunteers and six female patients suffering from anxiety neurosis, using a plastic paint impression method. Carbachol evoked consistently greater responses than phenylephrine. The response to carbachol attained a peak approximately two minutes after injection, whereas the response to phenylephrine attained a peak within fifteen seconds of the injection. Males showed greater responsiveness to both drugs than females, this being reflected in significantly higher maxima of the dose-response curves for the males. The anxious females showed a higher level of spontaneous sweat gland activity and greater responsiveness to both drugs (reflected in higher maxima of the dose-response curves) than the normal females.

Freeze-Fracture Examination of Tight Junctions of Human Eccrine Sweat Glands

1980 ◽  
Vol 38 ◽  
pp. 634-635
Author(s):  
J. V. Briggman ◽  
J. Bigelow ◽  
H. Bank ◽  
S. S. Spicer
Keyword(s):  
Cystic Fibrosis ◽  
Freeze Fracture ◽  
Sweat Glands ◽  
Hypertonic Solution ◽  
Dark Cells ◽  
Clear Cells ◽  
Junctional Complexes ◽  
Secretory Coil ◽  
Eccrine Sweat Glands ◽  
Eccrine Sweat

The prevalence of strands shown by freeze-fracture in the zonula occludens of junctional complexes is thought to correspond closely with the transepi-thelial electrical resistance and with the tightness of the junction and its obstruction to paracellular flow.1 The complexity of the network of junc¬tional complex strands does not appear invariably related to the degree of tightness of the junction, however, as rabbit ileal junctions have a complex network of strands and are permeable to lanthanum. In human eccrine sweat glands the extent of paracellular relative to transcellular flow remains unknown, both for secretion of the isotonic precursor fluid by the coil and for resorption of a hypertonic solution by the duct. The studies reported here undertook, therefore, to determine with the freeze-fracture technique the complexity of the network of ridges in the junctional complexes between cells in the secretory coil and the sweat ducts. Glands from a patient with cystic fibrosis were also examined because an alteration in junctional strands could underlie the decreased Na+ resorption by sweat ducts in this disease. Freeze-fracture replicas were prepared by standard procedures on isolated coil and duct segments of human sweat glands. Junctional complexes between clear cells, between dark cells and between clear and dark cells on the main lumen, and between clear cells on intercellular canaliculi of the coil con¬tained abundant anastomosing closely spaced strands averaging 6.4 + 0.7 (mean + SE) and 9.0 +0.5 (Fig. 1) per complex, respectively. Thus, the junctions in the intercellular canaliculi of the coil appeared comparable in complexity to those of tight epithlia. Occasional junctions exhibited, in addition, 2 to 5 widely spaced anastomosing strands in a very close network basal to the compact network. The fewer junctional complexes observed thus far between the superficial duct cells consisted on the average of 6 strands arranged in a close network and 1 to 4 underlying strands that lay widely separated from one another (Fig. 2). The duct epitelium would, thus, be judged slightly more "leaky" than the coil. Infrequent junctional complexes observed to date in the secretory coil segment of a cystic fibrosis specimen disclosed rela¬tively few closely crowded strands.

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