Table 5-2. Quantification of angiogenesis-related factors in juvenile and aged macaques ($\overline{X}\pm \text{s}$, pg/ml).

	n	HGF	Leptin	PDGF-BB	PIGF	VEGF
Young group	3	17.62 ± 25.21	60.46 ± 41.09	7.50 ± 7.02	0.18 ± 0.13	4.03 ± 1.20
Aged group	3	0.70 ± 1.18	337.42 ± 529.09	11.46 ± 13.29	3.24 ± 0.72*	0.00 ± 0.00*

Note: ^*Compared with the juvenile group, P < 0.05. The levels of HB-EGF and PIGF in the juvenile group were lower than those in the old group, while the levels of VEGF in the juvenile group were higher than those in the old group.