Russell H. Knutsen

Learn More
Mucopolysaccharidosis I (MPS I), known as Hurler syndrome in the severe form, is a lysosomal storage disease due to alpha-L-iduronidase (IDUA) deficiency. It results in fragmentation of elastin fibers in the aorta and heart valves via mechanisms that are unclear, but may result from the accumulation of the glycosaminoglycans heparan and dermatan sulfate.(More)
Signaling by hormones and neurotransmitters that activate G protein-coupled receptors (GPCRs) maintains blood pressure within the normal range despite large changes in cardiac output that can occur within seconds. This implies that blood pressure regulation requires precise kinetic control of GPCR signaling. To test this hypothesis, we analyzed mice(More)
OBJECTIVE Even though elastin and fibrillin-1 are the major structural components of elastic fibers, mutations in elastin and fibrillin-1 lead to narrowing of large arteries in supravalvular aortic stenosis and dilation of the ascending aorta in Marfan syndrome, respectively. A genetic approach was therefore used here to distinguish the differential(More)
The observations that atherosclerosis often occurs in non-smokers without elevated levels of low-density lipoprotein cholesterol, and that most atherosclerosis loci so far identified in mice do not affect systemic risk factors associated with atherosclerosis, suggest that as-yet-unidentified mechanisms must contribute to vascular disease. Arterial walls(More)
Elastic blood vessels provide capacitance and pulse-wave dampening, which are critically important in a pulsatile circulatory system. By studying newborn mice with reduced (Eln(+/)(-)) or no (Eln(-)(/)(-)) elastin, we determined the effects of altered vessel elasticity on cardiovascular development and function. Eln(-)(/)(-) mice die within 72 hours of(More)
Diseases linked to the elastin gene arise from loss-of-function mutations leading to protein insufficiency (supravalvular aortic stenosis) or from missense mutations that alter the properties of the elastin protein (dominant cutis laxa). Modeling these diseases in mice is problematic because of structural differences between the human and mouse genes. To(More)
Increased arterial stiffness and blood pressure are characteristic of humans and adult mice with reduced elastin levels caused by aging or genetic disease. Direct associations have been shown between increased arterial stiffness and hypertension in humans, but it is not known whether changes in mechanical properties or increased blood pressure occur first.(More)
BACKGROUND KATP channels, assembled from pore-forming (Kir6.1 or Kir6.2) and regulatory (SUR1 or SUR2) subunits, link metabolism to excitability. Loss of Kir6.2 results in hypoglycemia and hyperinsulinemia, whereas loss of Kir6.1 causes Prinzmetal angina-like symptoms in mice. Conversely, overactivity of Kir6.2 induces neonatal diabetes in mice and humans,(More)
Elastin is a major structural component of large elastic arteries and a principal determinant of arterial biomechanical properties. Elastin loss-of-function mutations in humans have been linked to the autosomal-dominant disease supravalvular aortic stenosis, which is characterized by stenotic lesions in both the systemic and pulmonary circulations. To(More)
Mice heterozygous for the elastin gene (ELN(+/-)) show unique cardiovascular properties, including increased blood pressure and smaller, thinner arteries with an increased number of lamellar units. Some of these properties are also observed in humans with supravalvular aortic stenosis, a disease caused by functional heterozygosity of the elastin gene. The(More)
  • 1