Forearm cutaneous vascular and sudomotor responses to whole body passive heat stress in young smokers.
The purpose of this study was to compare smokers and nonsmokers' sudomotor and cutaneous vascular responses to whole body passive heat stress. Nine regularly smoking (SMK: 29 ± 9 yr; 10 ± 6 cigarettes/day) and 13 nonsmoking (N-SMK: 27 ± 8 yr) males were passively heated until core temperature (TC) increased 1.5°C from baseline. Forearm local sweat rate (LSR) via ventilated capsule, sweat gland activation (SGA), sweat gland output (SGO), and cutaneous vasomotor activity via laser-Doppler flowmetry (CVC) were measured as mean body temperature increased (ΔTb) during passive heating using a water-perfused suit. Compared with N-SMK, SMK had a smaller ΔTb at the onset of sweating (0.52 ± 0.19 vs. 0.35 ± 0.14°C, respectively; P = 0.03) and cutaneous vasodilation (0.61 ± 0.21 vs. 0.31 ± 0.12°C, respectively; P < 0.01). Increases in LSR and CVC per °C ΔTb (i.e., sensitivity) were similar in N-SMK and SMK (LSR: 0.63 ± 0.21 vs. 0.60 ± 0.40 Δmg/cm(2)/min/°C ΔTb, respectively, P = 0.81; CVC: 82.5 ± 46.2 vs. 58.9 ± 23.3 Δ%max/°C ΔTb, respectively; P = 0.19). However, the plateau in LSR during whole body heating was higher in N-SMK vs. SMK (1.00 ± 0.13 vs. 0.79 ± 0.26 mg·cm(-2)·min(-1); P = 0.03), which was likely a result of higher SGO (8.94 ± 3.99 vs. 5.94 ± 3.49 μg·gland(-1)·min(-1), respectively; P = 0.08) and not number of SGA (104 ± 7 vs. 121 ± 9 glands/cm(2), respectively; P = 0.58). During whole body passive heat stress, smokers had an earlier onset for forearm sweating and cutaneous vasodilation, but a lower local sweat rate that was likely due to lower sweat output per gland. These data provide insight into local (i.e., forearm) thermoregulatory responses of young smokers during uncompensatory whole body passive heat stress.
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas.
Nicole E
NE
Moyen
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas.
Hannah M
HM
Anderson
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas.
Jenna M
JM
Burchfield
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas.
Matthew A
MA
Tucker
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas.
Melina A
MA
Gonzalez
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas.
Forrest B
FB
Robinson
Human Performance Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas msganio@uark.edu.
Matthew S
MS
Ganio
D000328:Adult; D000367:Age Factors; D005542:Forearm; D018882:Heat Stress Disorders / Q000503:physiopathology*; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply*; D012907:Smoking / Q000009:adverse effects / Q000503:physiopathology*; D013545:Sweat Glands / Q000294:innervation*; D013546:Sweating; D013997:Time Factors; D014664:Vasodilation; D014666:Vasomotor System / Q000503:physiopathology*; D055815:Young Adult
cigarette; nicotine; skin blood flow; sweating; thermoregulation