Laser Doppler flowmetry (LDF) is a reference technique to assess microcirculation perfusion signals, typically in the skin. It impinges a laser light through an organ and onto flowing red blood cells, which reflect it back. Flow is estimated through the Doppler shift, i.e., the difference between impinging and reflected laser frequencies. A major factor that influences the penetration depth is skin thickness. Provided the skin is sufficiently thin, light can probably reach large caliber vessels on the dermis/hypodermis. Our aim was to noninvasively characterize the LDF signal of large caliber vessels in murine hindlimb, using microcirculation LDF signals as comparison. Six C57/BL6 male animals (12 w.o.) were anesthetized with a ketamine-xylazine (137.5 mg/kg-11.0 mg/kg) i.p. mixture. All procedures involving animal experimentation were performed in accordance with the current ethical guidelines for the protection of animals used for scientific purposes in the EU. Twenty minutes after induction the animals were placed on a heated plate and LDF probes were attached to skin regions directly above large vessels (region 1 – macroLDF) and free of large vessels (region 2 – macroLDF). After 15 min stabilization, both LDF signals were measured for 30 minutes, after which they were decomposed in their spectral components with the wavelet transform. microLDF is believed to be composed of six spectral bands – cardiac, respiratory, myogenic, sympathetic, NO-dependent endothelial, NO-independent endothelial. macroLDF displayed bands in the same spectral regions although with significantly higher amplitude over the entire spectrum. The cardiac, sympathetic and NO-independent endothelial spectral bands showed higher resolution in the macroLDF, while respiratory and myogenic bands showed poor resolution with both signals. To the authors knowledge this is the first study to attempt to describe the spectral organization of macrocirculation signals.  Even considering that macroLDF signals might be partly overlaid with microLDF signals, these results suggest that large caliber vessels display similar spectral organization to microcirculation signals. This opens new possibilities to assess regional perfusion in real time during interventions, i.e., limb ischemia.