Author/Editor		Cankar, Ksenija; Štrucl, Martin
Title		The effects of glibenclamide on cutaneous laser-Doppler flux
Type		članek
Source		Microvasc Res
Vol. and No.		Letnik 75, št. 1
Publication year		2008
Volume		str. 97-103
Language		eng
Abstract		The KATP channels play a crucial role in regulation of vascular tone in conditions of hypoxia. Whether they contribute to peripheral blood flow regulation in human cutaneous microcirculation during a non-hypoxic state is the matter of conflicting in vivo studies that have used plethysmographic method. Our aim was therefore to elucidate the role of KATP channels in human skin microcirculation in three different conditions that evoke different interplays of vascular mechanisms; during resting conditions, during the postocclusive vasodilatation and in the vasoconstriction response to local cold exposure. The laser-Doppler (LD) skin response was monitored in 12 healthy volunteers on the skin of the fingertips of both hands at rest, after the release of an 8-min digital arteries occlusion, and during local cooling of one hand at 15°C. We compared the direct (at the measuring site) and the indirect (at the contralateral non-cooled hand) LD flux response after intradermal microinjection of saline solution (1 µl) and after a microinjection of the KATP channel blocker glibenclamide (8 µM saturated solution) at the measuring site after obtaining the dose-dependent effect of glibenclamide. The effect of the saline solution was used as a reference value. There was a statistically significant lower resting LD flux after the microinjection of glibenclamide 273.6 ± 36 PU when compared to the values obtained after the application of the saline solution 375.8 ± 31 PU (paired t-test, p = 0.016). Glibenclamide also significantly reduced the relative area under the LD flux curve during the PRH response 14551 ± 2508 PU*s vs. 6402 ± 1476 PU*s (paired t-test, p = 0.01) and increased the principal frequency of postocclusive PRH oscillations 0.0931 ±0.01 Hz vs. 0.1309 ± 0.02 Hz (p = 0.01). (Abstract truncated at 2000 characters)
Descriptors		SKIN MICROCIRCULATION GLYBURIDE LASER-DOPPLER FLOWMETRY POTASSIUM CHANNELS ADULT DOSE-RESPONSE RELATIONSHIP, DRUG