Aims: 

Hypertension is a cardiovascular disease associated with an increase in cardiovascular complications characterized by endothelial dysfunction and structural remodeling of vessel wall. Intercellular gap junction connexin-43 (C × 43) channels ensure direct communication between adjacent cells of arteries. Polyunsaturated fatty acids (PUFA) supplementation enhances protection against cardiovascular events. Therefore the aim of this study was to examine the effect of PUFA on ultrastructure of endothelial intercellular junctions and expression of connexin43 (C × 43) gap junction protein in aorta of spontaneously hypertensive rats (SHR).

Methods: 

1-year-old male SHR and nonhypertensive Lewis (LEW) rats were divided into four groups: 1) SHR rats untreated, 2) SHR treated with PUFA (30mg/day) for 2 months, 3) LEW untreated and 4) LEW treated with PUFA. Thoracic aorta of SHR and LEW were processed for: transmission electron microscopy, immunofluorescence, Western blot analysis of C × 43. Physiological functions of aorta were also determined.

Results: 

Electron microscopy revealed heterogeneous focal injury of structural integrity of aortic endothelial monolayer and intercellular junctions in aortas of untreated SHR while not in control LEW. It was demonstrated that there was reduced acetylcholine-induced relaxation of aorta in untreated SHR comparing with untreated LEW group. There were no differences in expression of C × 43 phosphorylated and dephosphorylated isoforms between untreated and treated SHR as well as untreated and treated LEW.

Conclusions: 

The results indicate that PUFA supplementation did not significantly affect neither expression of C × 43 in aorta nor function of aorta in both SHR and LEW.

Supported by grants: VEGA 2/5021 and APVV 51-059505.