A review on blood pressure and ischaemic white matter lesions
I. Skoog
Bok Engelsk 1998
| Utgitt | 1998
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| Omfang | Side 13- 19
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| Opplysninger | Hypertension or high blood pressure is constantly reported to be themain risk factors for ischaemic white matter lesions (WMLs), Theselesions show the histopathological picture of diffuse demyelinationand moderate loss of axons in subcortical structures, The mainhypothesis regarding the association between high blood pressure andischaemic WMLs is that long-standing hypertension causeslipohyalinosis of the media and thickening of the vessel walls withnarrowing of the lumen of the small perforating arteries andarterioles which nourish the deep white matter, Episodes ofhypotension may then lead to hypoperfusion and hypoxia-ischaemia inthe white matter, In line with this, low blood pressure has also beenreported to be a risk factor for WMLs, However, also otherpathogenetic mechanisms may be involved, Hypertension may causedisturbances in the blood-brain barrier, which may cause lesions inthe white matter by cerebral oedema, by activation of astrocytes orby destructive enzymes or other poisons which pass through thedamaged vessel walls, The renin-angiotensin system is an example of asystem that may be involved in the pathogenesis of both hypertensionand arteriosclerosis, Its effector peptide angiotensin II has severalblood-pressure-increasing effects, such as direct vasoconstrictionand activation of the sympathetic nervous system, It also promoteshyperplasia and hypertrophy in vascular smooth muscle cells, Recentlyan association between hypertension and Alzheimer's disease has beenreported, It is not clear whether this may be the reason for thecommon occurrence of WMLs in cases of late-onset Alzheimer's disease,as Alzheimer's disease may also cause lesions in the cerebralmicrovasculature, The association between WMLs and hypertension maythus be mediated through several different pathogenetic pathways.
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| Emner |
