Mechanoreceptor sensory feedback is impaired by pressure induced cutaneous ischemia on the human foot sole and can predict cutaneous microvascular reactivity

• DOI: 10.3389/fnins.2024.1329832
• Publication Date: 2024-04-02T08:07:59Z
• Authors: Erika E. Howe; Michael Apollinaro; Leah R. Bent
• Keywords: Mechanoreceptor; Reactive hyperemia

Introduction The foot sole endures high magnitudes of pressure for sustained periods which results in transient but habitual cutaneous ischemia. Upon unloading, microvascular reactivity capillaries generates an influx blood flow (PORH: post-occlusive reactive hyperemia). Whether induced ischemia from loading the impacts mechanoreceptor sensitivity remains unknown. Methods Pressure was attained using a custom-built-loading device that applied load to whole right at 2 (15 or 50% body weight), durations (2 10 minutes) thirteen seated participants. Mechanoreceptor assessed Semmes-Weinstein monofilaments over third metatarsal (3MT), medial arch (MA), and heel. Perceptual thresholds (PT) were determined each site prior then repeatedly metronome establish time course return PT upon unload, defined as recovery time. Microvascular flux recorded in-line laser speckle contrast imager (FLPI-2, Moor Instruments Inc.) PORH peak rates site. Results rate most influenced heel by duration rather than magnitude. significantly longer with minutes loading, regardless Heel slower 10minutes loading. 3MT only after weight. not MA. A simple linear regression found could predict ( R =0.184, p <0.001). Conclusion In populations degraded sensory feedback, such diabetic neuropathy, risk ulcer development is heightened. Our work demonstrated prolonged healthy individuals can impair skin sensitivity, highlights risks likely exacerbated diabetes. Understanding direct association between function age diabetes related nerve damage, help detect early progressions neuropathy mitigate development.