The skin hyperaemic response to local injection of substance P and capsaicin in diabetes mellitus

摘要: Recent studies have demonstrated impaired skin hyperaemia to local injury in diabetes mellitus. In order gain insight into the mechanisms of hyperaemia, dose-response curves intradermal substance P (25, 50, 100 pmol) and capsaicin (1.0, 2.5, 5.0 nmol) were examined before after histamine blockade with chlorpheniramine, 6 patients uncomplicated Type 1 9 matched control subjects. Skin was measured indirectly as peak laser Doppler flow proximity area hyperaemia. The response three doses significantly lower diabetic (0.37 ± 0.12 (± SD), 0.51 0.12, 0.67 0.09 V) than subjects (0.57 0.15, 0.70 0.19, 0.84 0.21 V; p < 0.01). contrast there no significant difference between (0.41 0.07, 0.50 0.09, 0.59 0.06, 0.52 0.08, 0.63 0.07 V). Following remained unaltered (0.39 0.05, 0.60 0.43 0.10, V subjects), but a reduction both (20.4 12.3% reduction, 0.05) (20.6 14.1% 0.05). It is suggested that may represent decreased vascular reactivity locally released from peripheral nerve fibres.