Table 3

Effect of in vitro application of IGF-1 on membrane resistance and resting chloride conductance of EDL and DIA muscle fibers of exercised mdx mice either untreated or IGF-1 treated

Experimental conditions	Drugs in Vitro	n	Rm	gGl
			Ω · cm ²	μS/cm ²
Exer mdx EDL		41	567 ± 33	1480 ± 76
	IGF-I 3.3 nM	28	437 ± 20^3-150	1930 ± 80^3-150
Exer mdx EDL, IGF-1-treated		50	423 ± 17	2161 ± 75
	IGF-I 3.3 nM	24	477 ± 25	1860 ± 77
Exer mdx DIA		16	595 ± 38	1344 ± 57
	IGF-I 3.3 nM	12	497 ± 30	1651 ± 56^3-150
Exer mdx DIA, IGF-1-treated		16	484 ± 28	1760 ± 62
	IGF-1 3.3 nM	12	549 ± 65	1652 ± 95

Each value is the mean ± S.E.M. for the n number of fibers sampled for 2 to 3 preparation. IGF-1 at 3.3 nM has been tested on Rm and gCl of EDL and DIA muscle fibers of both exercised mdx mice untreated (Exer mdx) and chronically treated with IGF-1 at the dose of 50 μg/kg (Exer mdx, IGF-1 treated).

↵3-150 Significantly different with respect to the relative control value in the absence of IGF-1 (p < 0.05 or less). Even if not indicated, according to what described in the text, the values of gCl of IGF-1-treated EDL and DIA muscle fibers were significantly higher with respect to those of untreated exercised counterparts.