Author/Editor		Lenasi, Helena
Title		Endotelijski hiperpolarizirajoči dejavnik in mikrocirkulacija kože
Translated title		Endothelium-derived hyperpolarizing factor and skin microcirculation
Type		članek
Source		Med Razgl
Vol. and No.		Letnik 47, št. 1
Publication year		2008
Volume		str. 13-29
Language		slo
Abstract		The skin microcirculation is controlled by systemic and local factors; the latter are mainly released from the endothelium. One of important endothelial vasodilators is endothelium-derived hyperpolarizing factor (EDHF) whose function can be assessed by blocking ocher vasodilators, such as nitric oxide (NO) and prostacyclin (PGIZ). The role and nature of EDHF in humans remains to be elucidated. The aim of our study was therefore to investigate and characterize the NO- and PGhindependent mechanism, potentially attributable to EDHF, in human skin microcirculation. 14 healthy male volunteers (aged 20 to 37 years, mean age 25.9 +- 1.7) were included in the study. Cutaneous blood flow was measured using the laser Doppler (LD) method on the volar aspect of the forearm and expressed in perfusion units (PU). Endothelial nitric oxide synthase (eNOS) and cyclooxygenase (COX) were inhibited by subcutaneously injecting N°'-monomethyl L-arginine (L-NMMA) and diclofenac, respectively. The potential involvement of cytochrome P450 (CYP) in the generation of EDHF was evaluated by injecting the selective CYP 2C9 inhibitor sulfaphenazole. The baseline LD flow and microvascular reactivity were assessed by performing iontophoresis of acetylcholine (ACh, endothelium-dependent vasodilator) and by measuring postocclusive reactive hyperemia (PRH). eNOS and COX inhibition did not affect the baseline LDF (12.5 +- 2.3 PU in the treated site and 10.9 +- 1.8 PU in the control site, t-test), but it significantly attenuated ACh-induced vasodilatation in the eNOS and COX-treated site (35.6+-5.7PU in the treated site vs. 66.6 +- 8.3 PU in the control site, t-test, p < 0.05). (Abstract truncated at 2000 characters)
Descriptors		SKIN MICROCIRCULATION LASER-DOPPLER FLOWMETRY ENDOTHELIUM, VASCULAR VASODILATION ADULT CYCLOOXYGENASE INHIBITORS DICLOFENAC NITRIC-OXIDE SYNTHASE IONOPHORES PROSTAGLANDINS CYTOCHROME P-450