Figure 5

Angiotensin II abolishes Ni²⁺’s ability to inhibit STOCs and augment myogenic tone. (A) Representative traces and summary data showing Ni²⁺ (50 µM)-induced inhibition of STOC frequency in absence (n = 6) and presence (n = 6) of Ang II (100 nM). Perforated patch clamp electrophysiology was used to measure STOCs in cerebral arterial smooth muscle cells held at −40 mV. (B) Representative trace and summary data comparing the effect of Ni²⁺ on myogenic tone (60 mmHg) in absence (n = 5) and presence (n = 5) of Ang II. Ni²⁺ failed to alter arterial tone in vessels pretreated with Ang II, a phenomenon reversed with Nox inhibition with apocynin (50 µM) (n = 5). *Denotes significant difference (*P < 0.05, paired t test).