Adherent Primary Cultures of Mouse Intercostal Muscle Fibers for Isolated Fiber Studies

Figure 5

Comparison of electrically evoked Ca²⁺ transients between intercostal and FDB fibers. Average fluo4 Ca²⁺ transient from FDB ((a), red trace; 𝑛=9) or intercostals fibers ((b), ITC, green trace; 𝑛=9) in response to 5 sec 10 Hz train field stimulation. Traces in (c) were normalized to the amplitude of the initial response. At the end of the 5 sec train, ITC fibers demonstrated significantly smaller relative decrease of Ca²⁺ transient amplitude compared to FDB counterparts (𝑃<0.05). ITC muscle fibers exhibit decreased peak amplitude of the fluo-4 Ca²⁺ transients in response to a single field stimulus; however, the intercostals are able to maintain consistent levels of calcium during repetitive stimulation. Fluorescence was detected as in Figure 4.

(a)

(b)

(c)