Table 3.

Natriuretic peptide concentration, collagen content, and titin isoform expression in the left ventricular epicardium vs endocardium.

	Normal (NL, n=6)	Heart Failure (HF, n=6)	p HF vs NL
ANP (pg/mg protein )
epicardial	1.7 ± 0.4	4.0 ± 5.5	0.8
endocardial	7.8 ± 5.2*	23 ± 9*	0.01
cBNP (pg/ mg protein)
epicardial	1.0 ± 0.5	1.5 ± 0.3	0.06
endocardial	1.3 ± 0.5	8.0 ± 6.5*	0.004
Collagen (μg/mg tissue)
epicardial	5.5 ± 0.8	5.3 ± 0.9	0.7
endocardial	5.0 ± 1.6	4.5 ± 0.6	0.5
Collagen volume fraction (%)
epicardial	2.21 ± 0.92	1.99 ± 1.17	0.8
endocardial	1.27 ± 0.74	1.79 ± 1.43	0.4
Titin N2BA:N2B ratio
epicardial	0.66 ± 0.09	0.52 ± 0.07	0.03
endocardial	0.70 ± 0.09	0.71 ± 0.15*	0.8

^*p < 0.05 vs epicardial

Abbreviations: ANP, atrial natriuretic peptide; cBNP, canine brain natriuretic peptide; LV, left ventricular