Table 1.

Effect of Aging on Physical Characteristics F344BN Rats

	9 Months (n = 6)	24 Months (n = 6)	33 Months (n = 6)
Body weight (g)	409.3 ± 41.7	575.2 ± 33.1*	581.9 ± 50.6*
Ventricular weight (g)	0.95 ± 0.11	1.32 ± 0.12*	1.42 ± 0.17*
Tibia length (mm)	41.3 ± 0.76	43.4 ± 0.38*	46.2 ± 0.43*
Heart weight/body weight × 1,000	2.32 ± 0.03	2.34 ± 0.23	2.44 ± 0.33
Heart weight/tibia length × 1,000	23.00 ± 2.66	30.41 ± 2.08*	30.74 ± 3.68*

Notes: Values are means ± SD. n = number of animals.

*Significantly different from 9 months at p < .05.