Morphological changes of cell proliferation and apoptosis in rat jejunal mucosa at different ages

Table 1 Developmental changes in cell type and morphology of rat villi after staining (^-x±s, n = 6)

Group	Number of villus goblet cells (entries/μm2)	Number of crypt goblet cells (entries/μm2)	Thickness of muscle layer (μm)	Villus height (μm)
Newborn group	4.89 ± 2.67	0 ± 0	32.0 ± 15.71	315.20 ± 43.74
Postnatal 3rd week	7.14 ± 1.54b	4.47 ± 1.10b	64.86 ± 14.91b	532.75 ± 53.36b
Postnatal 3rd month	4.44 ± 1.11	5.27 ± 0.93	56.34 ± 15.41	629.64 ± 48.22
Postnatal 1 year	9.31 ± 1.50d	6.49 ± 1.98	60.48 ± 11.93	510.95 ± 82.93d

^bP < 0.01, vs Newborn group.

^dP < 0.01, vs Postnatal 3^rd month.

Table 2 Surface densities of PCNA-positive cells and the number of apoptotic cells at different stages (^-x±s, n = 6)

Age	Surface densities of PCNA-positive cells	The number of apoptotic cells
Newborn group	0 ± 0	0 ± 0
Postnatal 3rd week	0.022 ± 0.012	9.71 ± 2.43
Postnatal 3rd month	0.449 ± 0.063b	38.83 ± 7.41b
Postnatal 1 year	0.096 ± 0.045d	11.36 ± 3.14d

^bP < 0.01, vs Postnatal 3^rd week.

^dP < 0.01, vs Postnatal 3^rd month.