TITLE:
Effect of Peroxynitrite (ONOO-) on the Function of Murine Perivascular Adipose Tissue
AUTHORS:
Azizah Binti Ugusman, Alex Riddell, Simon Kennedy
KEYWORDS:
Perivascular Adipose Tissue (PVAT), Peroxynitrite, Nitric Oxide, Adiponectin, Anticontractile
JOURNAL NAME:
Pharmacology & Pharmacy,
Vol.10 No.4,
April
23,
2019
ABSTRACT:
Perivascular adipose tissue (PVAT) surrounds the
exterior of blood vessels and releases numerous substances such as adiponectin
which positively modulate blood vessel tone. In some cardiovascular diseases
such as diabetes and high blood pressure, the function of PVAT changes and we speculate that oxidant stress may play a role in this change.
PVAT has the ability to generate both superoxide and nitric oxide and these can
combine rapidly under physiological conditions to form peroxynitrite (ONOO-).
In disease states, the production of ONOO- may be increased and so
its effect on the function of PVAT is of great interest. Consequently, we
studied the effects of acute addition of the oxidant species ONOO- on vascular tone and production of adiponectin by mouse thoracic aortic
PVAT. Murine PVAT was immunostained for
nitrotyrosine, indicating that ONOO- is formed in the PVAT.
Exogenous ONOO- significantly increased the anticontractile effect
of PVAT via increased adiponectin content but had no effect on eNOS expression
or phosphorylation. These results suggest that generation of ONOO- within PVAT may be an important regulatory mechanism which influences the
activity of PVAT. The effect of chronic exposure to raised levels of ONOO- on PVAT function remains to be determined.