Structural changes of thoracic aorta (TA), carotid (CA) and iliac artery (IA) were assessed in Wistar and spontaneously hypertensive rats (SHR) aged 3, 17, and 52 weeks. Systolic blood pressure (sBP) was measured by plethysmography weekly. After perfusion fixation the arteries were processed for electron microscopy. The wall thickness (WT), cross-sectional area (CSA), inner diameter (ID), and WT/ID in all arteries and volume densities of endothelial cells (ECs), muscle cells (SMCs), and extracellular matrix (ECM) in TA were measured and their CSAs were calculated. In 3-week-old SHR compared to Wistar rats, sBP did not differ; in the TA, all parameters (WT, CSA, ID, WT/ID, CSA of SMCs, CSA of ECs, and CSA of ECM) were decreased; in CA, WT and CSA did not differ, ID was decreased, and WT/ID was increased; in IA, WT, CSA, and ID were increased. In 17- and 52-week-old SHRs, sBP and all parameters in all arteries were increased, only ID in IE in 52-week-old SHRs and CSA of ECs in the TA in 17-week-old SHRs did not change. Disproportionality between BP increase and structural alterations during ontogeny in SHR could reflect the flexibility of the arterial tree to the different needs of supplied areas.

• MeSH
• aorta thoracica patologie   patofyziologie   MeSH
• arteria iliaca patologie   patofyziologie   MeSH
• arteriae carotides patologie   patofyziologie   MeSH
• hypertenze patologie   patofyziologie   MeSH
• krevní tlak fyziologie   MeSH
• krysa rodu Rattus MeSH
• potkani inbrední SHR MeSH
• potkani Wistar MeSH
• tunica intima patologie   patofyziologie   MeSH
• věkové faktory MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

Elevated levels of insulin have been reported to induce both an arterial vasodilation mediated by nitric oxide (NO), and vasoconstriction mediated by endothelin and reactive oxygen radicals. Metformin, used to control blood glucose levels in type 2 diabetes, has also been shown to cause NO-mediated dilation of conduit arteries. It is possible that these contradictory vascular effects are due to a non-direct action on arteries. Therefore, the direct effect of high levels of insulin and metformin infusion on resistance artery diameter was evaluated. Experiments were carried out on the anesthetized pig; blood flow and pressure were measured in the iliac artery. An adjustable snare was applied to the iliac above the pressure and flow measurement site to induce step decreases (3-4 occlusions at 5 min intervals were performed for each infusion) in blood flow, and hence iliac pressure, and the conductance (deltaflow / deltapressure) calculated. Saline, insulin (20 and 40 mUSP/l/min), and metformin (1 microg/ml/min) were infused separately downstream of the adjustable snare and their effect on arterial conductance assessed. Insulin at both infusion rates and metformin caused a significant reduction in peripheral vascular conductance. In conclusion, hyperinsulinemia and metformin infusion constrict resistance arterial vessels in vivo.

• MeSH
• arteria iliaca účinky léků   patofyziologie   MeSH
• celková anestezie * MeSH
• hyperinzulinismus chemicky indukované   patofyziologie   MeSH
• hypoglykemika aplikace a dávkování   farmakologie   MeSH
• intravenózní infuze MeSH
• inzulin MeSH
• krevní tlak MeSH
• metformin aplikace a dávkování   farmakologie   MeSH
• modely nemocí na zvířatech MeSH
• prasata MeSH
• regionální krevní průtok MeSH
• rychlost toku krve MeSH
• vazokonstrikce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• hypoglykemika MeSH
• inzulin MeSH
• metformin MeSH

The aim of this study was to compare the vascular reactivity and morphology of iliac artery (IA) in adult spontaneously hypertensive rats (SHR) and hereditary hypertriglyceridemic (hHTG) rats. The isolated rings of iliac artery (IA) from Wistar rats (controls), SHR and hHTG rats were used for measurement of relaxant responses to acetylcholine (ACh) and contractile responses to noradrenaline (NA). Morphological changes of IA were measured using light microscopy. Systolic blood pressure (BP) measured by plethysmographic method was increased in SHR approximately by 88 % and in hHTG rats by 44 % compared to controls. BP increase was accompanied by cardiac hypertrophy. In both SHR and hHTG groups (experimental groups) reduced relaxation to ACh and enhanced maximal contraction and sensitivity to adrenergic stimuli were observed. The sensitivity to NA in SHR was higher also in comparison with hHTG. Geometry of IA in both experimental groups revealed increased wall thickness and wall cross-sectional area, in SHR even in comparison with hHTG. Inner diameter was decreased in both experimental groups. Thus, independently of etiology, hypertension in both models was connected with impaired endothelial function accompanied by structural alterations of IA. A degree of BP elevation was associated with arterial wall hypertrophy and increased contractile sensitivity.

• MeSH
• acetylcholin farmakologie   MeSH
• arteria iliaca účinky léků   patologie   patofyziologie   MeSH
• hypertenze etiologie   patologie   patofyziologie   MeSH
• hypertriglyceridemie patologie   patofyziologie   MeSH
• krysa rodu Rattus MeSH
• noradrenalin farmakologie   MeSH
• potkani inbrední SHR MeSH
• potkani Wistar MeSH
• vazodilatace MeSH
• vazodilatancia farmakologie   MeSH
• vazokonstrikce MeSH
• vazokonstriktory farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• acetylcholin MeSH
• noradrenalin MeSH
• vazodilatancia MeSH
• vazokonstriktory MeSH

• MeSH
• arteria iliaca patofyziologie   MeSH
• časové faktory MeSH
• ischemie patofyziologie   MeSH
• krysa rodu Rattus MeSH
• ligace MeSH
• modely nemocí na zvířatech MeSH
• rychlost toku krve MeSH
• svaly krevní zásobení   MeSH
• xenon MeSH
• zadní končetina MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• xenon MeSH