Scientific Publications Database

Article Title: Type 2 diabetes specifically attenuates purinergic skin vasodilatation without affecting muscarinic and nicotinic skin vasodilatation and sweating
Authors: Fujii, Naoto; Meade, Robert D.; McNeely, Brendan D.; Nishiyasu, Takeshi; Sigal, Ronald J.; Kenny, Glen P.
Journal: EXPERIMENTAL PHYSIOLOGY Volume 103 Issue 2
Date of Publication:2018
Abstract:
The present study evaluated whether type 2 diabetes (T2D) attenuates muscarinic and/or nicotinic cutaneous vasodilatation and sweating as well as purinergic cutaneous vasodilatation. Cutaneous vascular conductance and sweat rate were evaluated in 12 healthy non-diabetic older adults (Control, 60 +/- 8years) and 13 older adults with T2D (62 +/- 10years) at three intradermal forearm skin sites perfused with the following: (i) methacholine (muscarinic receptor agonist, five doses: 0.0125, 0.25, 5, 100 and 2000mm); (ii) nicotine (nicotinic receptor agonist, five doses: 1.2, 3.6, 11, 33 and 100mm); or (iii) ATP (purinergic receptor agonist, five doses: 0.03, 0.3, 3, 30 and 300mm). Each agonist was administered for 25min per dose. At the end of the protocol, 50mm sodium nitroprusside was administered to all skin sites to elicit maximal cutaneous vasodilatation. Cutaneous vascular conductance during methacholine and nicotine administration did not differ between groups (all P>0.05). In contrast, cutaneous vascular conductance during administration of 30mm (42 +/- 28 versus 63 +/- 26% maximum, P0.05) and 300mm ATP (56 +/- 24 versus 71 +/- 20% maximum, P0.05) was attenuated in individuals with T2D in comparison to the Control participants. Furthermore, cutaneous vascular conductance during administration of 50mm sodium nitroprusside was lower in individuals with T2D relative to Control subjects (P=0.04). Methacholine- and nicotine-induced sweating was similar between groups (all P>0.05). Thus, T2D attenuates purinergic cutaneous vasodilatation without affecting muscarinic and nicotinic cutaneous vascular and sweating responses.