Book of Abstracts - New Frontiers 2022

Abstracts of poster presentations

NEUROGENIC REGULATION OF SPLANCHNIC ARTERIES IN RATS TREATED WITH HIGH-FAT DIET IN COMBINATION WITH HIGH-FRUCTOSE INTAKE

J. Török, A. Zemančíková, P. Bališ

Institute of Normal and Pathological Physiology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovakia

The aim was of this study was to examine the effects of obesitogenic diet on the mechanisms of neurogenic regulation in arteries of rat splanchnic area. Six-week-old Wistar-Kyoto rats were treated for 8 weeks with control diet (10 % fat), high-fat diet (HFD; 45 % fat), or combination of HFD with 10 % solution of fructose. Contractile and relaxant responses of isolated rat arteries (mesenteric artery, aorta) with preserved and removed perivascular adipose tissue to selected vasoactive stimuli were recorded isometrically by the force displacement transducer. The results demonstrated that in young rats the eight-week-lasting HFD might lead to body fat accumulation and early excitation of cardiovascular sympathetic nervous system, as shown by increased heart rate and enhanced arterial contractile responses induced by endogenous noradrenaline released from perivascular sympathetic nerves. The addition of high-fructose intake deteriorated this state by impairment of arterial relaxation and resulted in mild elevation of systolic blood pressure; however, it did not cause the increase in sympathetic contractions observed after treatment with HFD alone, indicating the attenuating effect of high-fructose treatment on arterial sympathoadrenergic responses. It might be presumed that during electrical stimulation of perivascular nerves in isolated arterial preparations, the increased sensoric nerve activity might inhibit the resultant sympathetic contraction, an effect which could be responsible for the elimination of the enhancement of arterial contractile responses to electrical nerve stimulation when HFD was combined with high-fructose intake. The diet-induced alterations in isolated arteries were observed only in the presence of perivascular adipose tissue, indicating that this structure is important in initiation of early vascular changes during the development of metabolic syndrome.

Keywords: arteries; neurogenic regulation; high-fat diet; high-fructose intake; perivascular adipose tissue

Funding:The study was funded by the grants VEGA No. 2/0156/21 and 2/0153/21.

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