Author/Editor     Poredoš, Pavel
Title     Arterijska hipertenzija in mikrocirkulacija
Translated title     Arterial hypertension and microcirculation
Type     članek
Source     Med Razgl
Vol. and No.     Letnik 35, št. Suppl 2
Publication year     1996
Volume     str. 145-52
Language     slo
Abstract     The basic pathophysiological change in arterial hypertension in increased peripheral resistance. The centre of this process is therefore in the area of microcirculation (small arteries and arterioles). In the development of this disease, functional changes probably appear first, followed by structural changes in the area of resistance arteries. Functional changes include increased vasoconstriction and a resulting increase in peripheral resistance. These most probably occur due to an increased sensitivity of smooth muscle cells in small arteries and arterioles to various stimuli, and a local increase in the synthesis of angiotensin 2 and endothelial disorders, functions which are reflected in a disturbed equilibrium between the release of factors with vasodilatory and vasoconstrictor effects probably contribute to the process. Morphological changes in microcirculation include: thickening of the walls of resistance arteries which is a consequence of hypertrophy and hyperplasia of smooth muscle cells, a reduction in the cross-section of small arteries, a remodelling of vessel structure and a rarefaction of terminal arterioles. Microcirculation is also one of the most important target organs on which the harmful effects of increased blood pressure are most expressed. The changes in microcirculation therefore have a predictive value for the assessment of the condition of vital organ systems. In the future the assessment of the success of the treatment of hypertension will probably be based on the monitoring of changes in the area of microcirculation, since the goal of the treatment of hypertension is not only to reduce blood pressure, but above all to prevent target organs from being affected.
Summary     Temeljna patofiziološka sprememba pri arterijski hipertenziji je zvečan periferni upor. Sedež dogajanja je torej v območju mikrocirkulacije (male arterije in arterole). V razvoju bolezni se najprej pojavijo funkcijske, tem pa sledijo strukturne spremembe v območju uporovnih arterij. Med funkcijske spremembe sodi zvečana vazokonstrikcija in posledično zvečanje perifernega upora. Do teh sprememb pride najverjetneje zaradi povečane občutljivosti gladkih mišičnih celic v malih arterijah in arteriolah na različne dražljaje, pri tem pa sodeluje tudi lokalno zvečanje tvorbe angiotenzina-2 ter motnje funkcije endotelija, ki se kažejo v porušenem razmerju sproščanja dejavnikov z vazodilatatornim in vazokonstriktornim učinkom. Med morfološke spremembe v mikrocirkulaciji sodijo: zadebelitev stene uporovnih arterij, ki temelji na hipertrofiji in hiperplaziji gladkih mišičnih celic, zmanjšanje svetline malih arterij, remodeliranje žilne strukture in razredčitev terminalnih arteriol. Mikrocikrulacija pa je tudi eden najpomembnejših tarčnih sistemov, kjer pridejo kvarni učinki zvečanega krnvega tlaka najbolj do izraza. Zato imajo spremembe v mikrocirkulaciji pomembno napovedano vrednost za oceno prizadetosti življenjsko važnih organskih sistemov. Verjetno bo v bodoče ocenjevanje uspešnosti antiipertenzivnega zdravljenja temeljilo tudi na prepoznavanju in spremljanju sprememb v območju mikrocirkulacije, kajti cilj antihipertenzivnega zdravljenja ni le znižanje krvnega tlaka, ampak predvsem preprečevanje prizadetosti tarčnih organov.
Descriptors     HYPERTENSION
MICROCIRCULATION
VASCULAR RESISTANCE