Fig. 5

Inhibition of Ca²⁺ sparks with ryanodine results in a modest increase in global [Ca²⁺]_i but does not constrict the SMA at 60 cmH₂O. a Representative recordings of [Ca²⁺]_i changes from single smooth muscle cells from a pressurized (60 cmH₂O) SMA superfused with HEPES-buffered PSS in response to 10 μM Ryn. b Average of normalized traces of [Ca²⁺]_i changes at 60 cmH₂O (54 cells). Traces in a and b were normalized as described in Methods. c Average trace of corresponding changes in vascular diameter (6 arteries). Diameter changes were normalized to the average of values recorded between 30 – 60 s (average value indicated by ‘a’ was set to 1). [Ca²⁺]_i and diameter data were simultaneously acquired at 1 s intervals, however, for clarity, error bars (sem) are plotted only every 10 s