Increased expression of NOS and ET-1 immunoreactivity in human colorectal metastatic liver tumours is associated with selective depression of constitutive NOS immunoreactivity in vessel endothelium.
G Aliev, MA Smith, D Seyidova, ML Neal, J Shi, M Loizidou, M Turmaine, RP Friedland, I Taylor, G Burnstock, G Perry, JC Lamanna
Journal of Submicroscopic Cytology and Pathology | Published : 2002
The absence of perivascular nerves in tumour vessels suggests that endothelium derived vasoactive substances [nitric oxide (NO) and endothelin-1 (ET-1)] may be key factors in controlling tumour blood flow during tumour growth and metastasis. We have studied the ultrastructural distribution and immunoreactivity of different NO synthase (NOS) isoforms and ET-1 in human colorectal metastatic liver tumour tissues using pre-embedding peroxidase-anti-peroxidase and post-embedding immunoelectron microscopic triple gold labelling techniques. Dramatically lower NOS 1 immunoreactivity was observed in tumour vascular endothelium (1-3% and 15-20% in tumour and normal groups, respectively). As compared t..View full abstract