Aortic large-conductance calcium activated potassium channel and potassium channel with inwardly rectification are differently expressed in normotensive and hypertensive rats

SOSA, AGUSTINA; SORIA, DAMIÁN ARIEL; RAMÍREZ, HERNÁN; TOMAT, ANALÍA; ELESGARAY, ROSANA; ARRANZ, CRISTINA; CANIFFI, CAROLINA

Congreso; Reunión Anual de Sociedades de Biociencia; 2020

SAIC - SAI - SAFIS

Potassium channels and C-type natriuretic peptide (CNP) play key roles in the regulation of vascular tone. Objective: to evaluate the aortic expression of BKCa and Kir channels in spontaneously hypertensive rats (SHR) and their role in the vasodilator effect of CNP.Experimental design: Male Wistar rats and SHR (14 weeks-old) were sacrificed and aorta was removed to determine: BKCa and Kir2.0 protein expression and vascular reactivity after CNP addition (1pmol/L - 1umol/L). Denuded aortic rings were pre-contracted with phenylephrine (1umol/L) in the presence or absence of tetraethylammonium (TEA, non-selectively potassium channel blocker, 1mmol/L), iberiotoxin (IbTx, BKCa blocker, 30nmol/L), or BaCl2 (Kir blocker, 30 umol/L). Statistical analysis: Results are expressed as mean±SEM, Student t-test or 2-way ANOVA, followed by Bonferroni posthoc test; n=4-6/group.Results: Protein content of BKCa and Kir2.0 was lower in SHR compared to Wistar rats (BKCa: Wistar=1.1±0.1 vs. SHR=0.7±0.1*; Kir2.0: Wistar=0.8±0.1 vs. 0.4±0.1*; *p