Figures and data
TRPV4 localization in eccrine glands of mouse foot pads.
(A) TRPV4 signals in the secretory coil in the deep dermis with a relatively straight duct opening to the skin surface. (B) Localization of TRPV4 (green), cytokeratin 8 (CK8; yellow) and anoctamin 1 (ANO1; magenta) in the skin. (C, D, E) Highly magnified Airyscan super-resolution images of the sweat duct (C) and secretory portion (D, E). (C) TRPV4 localizes to the basal cells of the bilayered sweat duct. Ductal lumen: L. (D) Secretory gland showing labeling for TRPV4 and calcitonin gene-related peptide (CGRP). (E) Secretory gland with conspicuous TRPV4 labeling in myoepithelial cells (M) and secretory cells. TRPV4 clearly colocalizes with aquaporin-5 (AQP5), F-actin, and ANO1 at the luminal side of the secretory cells. Arrows indicate the glandular lumen. Differential interference contrast: DIC, Nuclei: DAPI. Scale bar: 50 μm (A, B). 5 μm (C-E).
Functional TRPV4 expression in mouse sweat gland acinar cells.
(A, B) Changes in cytosolic Ca2+ concentrations upon stimulation with GSK, acetylcholine or ionomycin in sweat gland acinar cells from wild-type (WT, A) and TRPV4-deficient (TRPV4, B) mice. n=6 experiments for WT and TRPV4KO sweat glands.(C) Changes in cytosolic Ca2+ concentration upon stimulation with GSK in the presence (red) or absence (blue) of menthol in sweat gland acinar cells from WT mice.
Stimulated sweating in mouse hind paws at different temperatures.
(A, left) Representative stimulated sweat spots formed at 25 °C or 35 °C in hind paws of WT and TRPV4KO mice 2 min after injection of acetylcholine. (A, right) Comparison of sweat spots/paws at 25 °C or 35 °C in WT and TRPV4KO mice (box-whisker plot). n = 8∼10 for WT or TRPV4KO. NSp ≥ 0.05, *p < 0.05, **p < 0.01 between indicated pairs. (B, left) Representative sweat spots at 25 °C or 35 °C in hind paws of WT and TRPV4KO mice without acetylcholine stimulation at 15 min. (B, right) Comparison of sweat spots/paw at 25 °C or 35 °C for WT and TRPV4KO mice (box-whisker plot). n = 9∼10 for WT or TRPV4KO. NSp ≥ 0.05, *p < 0.05, ***p < 0.001 between indicated pairs. (C and D, left) Representative stimulated sweat spots at 25 °C in hind paws of WT (C) and TRPM8KO (D) mice 2 min after injection of acetylcholine with or without menthol. (C and D, right) The effect of menthol on sweat spots/paw at 25 °C in WT (C) and TRPM8KO (D) mice (box-whisker plot). n = 8∼9 for with or without menthol. *p < 0.05. (D and E, left) Representative sweat spots without acetylcholine stimulation at 25 °C (E) and 35 °C (F) in hind paws of WT mice with or without Ani9. (D and E, right) The effect of Ani9 on sweat spots/paw at 25 °C (E) and 35 °C (F) in WT mice (box-whisker plot). n = 4∼6 for with or without Ani9. ***p < 0.001.
Climbing behaviors on a slippery slope.
(A) A mouse in a cage containing the vinyl slope. (B) Number of attempts made by WT and TRPV4KO mice within 60 min. (C) Successful (climbing) and failed (slipping) climbing behaviors exhibited by WT and TRPV4KO mice within 60 min. Different colors indicate individual mice. n = 5 for both WT and TRPV4KO. (D) Comparison of climbing success rates between WT and TRPV4KO mice. * p < 0.05.
TRPV4 expression in human sweat glands.
Representative TRPV4 staining in sweat glands from normohidrotic (A) and anhidrotic (B) skin from the same patient with AIGA. Scales bars: 50 μm. (C) Scored TRPV4 expression levels in normohidrotic skin from patients with AIGA and Controls (melanocytic nevus) versus anhidrotic skin from patients with AIGA. *** p < 0.001.
