Barnidipine is a calcium-channel blocker.

A calcium channel, an ion channel which displays selective permeability to calcium ions, is sometimes synonymous as voltage-dependent calcium channel, although there are also ligand-gated calcium channels.

In vitro: The effects of barnidipine on L-type Ca(2+) current (I(Ca(L))) were investigated in rat ventricular cardiomyocytes. It was found that barnidipine reduced I(Ca(L)) in a concentration and voltage dependent manne. Barnidipine induced a leftward shift of the steady-state inactivation curve of I(Ca(L)) [1].

In vivo: A previous study was conducted to investigate the influence of barnidipine treatment on early stage hypertension by determining the mesenteric and renal arteries as well as the kidney in L-NAME-induced hypertensive rats. Barnidipine was applied to rats after 2 weeks of L-NAME administration, and continued for the next 3 weeks concomitantly with L-NAME. Histopathological studies verified structural alterations in the arteries and the kidney. Moreover, a decrease in endothelial nitric oxide synthase expression was observed both in the arteries and kidney of hypertensive rats with barnidipine treatment [2].

Clinical trial: In patients with hypertension and type 2 diabetes mellitus, it was found that barnidipine treatment led to a significant reduction in blood pressure. Data recorded with ABPM also showed a similar trend. Barnidipine + losartan could reduce the levels of Hs-CRP, TNF-α, sVCAM-1, sICAM-1, and isoprostanes [3].

References:
[1] Wegener JW, Meyrer H, Rupp J, Nawrath H. Barnidipine block of L-type Ca(2+) channel currents in rat ventricular cardiomyocytes. Br J Pharmacol. 2000 Aug;130(8):2015-23.
[2] Alp Yildirim FI, Eker Kizilay D, Ergin B, Balci Ekmeki, Topal G, Kucur M, Demirci Tansel C, Uyde Doan BS.  Barnidipine ameliorates the vascular and renal injury in L-NAME-induced hypertensive rats. Eur J Pharmacol. 2015 Oct 5;764:433-42.
[3] Derosa G, Mugellini A, Pesce RM, D'Angelo A, Maffioli P.  Barnidipine compared to lercanidipine in addition to losartan on endothelial damage and oxidative stress parameters in patients with hypertension and type 2 diabetes mellitus. BMC Cardiovasc Disord. 2016 Apr 12;16:66.