TITLE:
The Influence of Perivascular Adipose Tissue on Vascular Function in a Rabbit Model
AUTHORS:
Abdulqader Abdulrazzaq, Simon Kennedy
KEYWORDS:
Perivascular Adipose Tissue, Nitric Oxide, Myography
JOURNAL NAME:
Pharmacology & Pharmacy,
Vol.11 No.12,
December
16,
2020
ABSTRACT: The recent acknowledgment of the paracrine role of perivascular adipose
tissue (PVAT) in vascular modulation has been supported by many studies
investigating major arteries in several animal models and humans. The influence
of PVAT on the functional activity of the vascular bed has been a matter of
debate, whether it is an anticontractile effect with protective roles or a pro-contractile effect, investigations are
underway to address this obscurity.
In this investigation, we have studied the effects of vasoconstrictors, phenylephrine and noradrenaline, and vasorelaxants, carbachol and s-nitroso-n- acetylpenicillamine (SNAP),
on subclavian and iliac rings with and without PVAT attached; and
concentration-response curves were constructed accordingly. Levels of nitric
oxide (NO) generated due to activation of the enzyme adenosine
monophosphate-activated protein kinase (AMPK) by 5-Aminoimi- dazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) were measured
in sub- clavian and iliac PVAT conditioned media. Additionally, Haematoxylin and
Eosin staining was performed to analyze and compare the histological
characteristics of both arteries. Subclavian and iliac rings with PVAT attached
showed stronger contraction to phenylephrine and noradrenaline than that of rings without PVAT attached. At the same time,
relaxation tests reported lower
relaxation percentages in subclavian and iliac rings with PVAT attached compared to rings without PVAT attached in response
to carbachol and SNAP. PVAT treated with AICAR generated higher levels
of NO compared to levels of untreated PVAT. Conclusions drawn were the
pro-contractile effects demonstrated by the PVAT especially in high
concentrations of drugs used. In addition, histology analysis revealed
characteristics of white adipose tissue in both PVATs.