Table 2.

Morphometric variables for ad libitum–fed and calorie-restricted heterozygous AA-4E-BP1 rats nephrectomized at 300-g body weight

Variable	Ad Libitum Diet			Calorie-Restricted Diet			Fold Change: Ad Libitum versus Calorie-Restricted Diets
	Control (n=5)	8 wk (n=5)	Fold Change versus Control	Control (n=5)	8 wk (n=5)	Fold Change versus Control
Glomerular tuft volume (μm3)
mean	988,394	1,537,509	1.6	988,509	829,346	0.8	1.9
SD	178,504	331,376		189,784	149,557
P value within each group	<0.01			NS
P value between groups	NS	<0.01
GLPP1-positive tuft area (%)
mean	57	43	0.8	55	53	1.0	0.8
SD	6	9		4	4
P value within each group	<0.01			NS
P value between groups	NS	NS
GLPP1-positive volume (μm3)
mean	557,405	640,941	1.1	538,970	435,234	0.8	1.5
SD	101,091	41,783		104,964	75,625
P value within each group	0.03			NS
P value between groups	NS	<0.01
Podocytes per tuft (n)
mean	116	132	1.1	106	128	1.2	1.0
SD	11	41		8	26
P value within each group	NS			NS
P value between groups	NS	NS
GV/P (μm3)
mean	8552	12453	1.5	9253	6518	0.7	1.9
SD	1676	3927		1302	696
P value within each group	<0.01			<0.01
P value between groups	NS	0.01
Mean podocyte volume (μm3)
mean	4826	5221	1.1	5032	3436	0.7	1.5
SD	970	1627		637	466
P value within each group	NS			<0.01
P value between groups	NS	0.05
GLEPP1-negative tuft volume (μm3)
mean	430,989	896,567	2.1	449,538	394,112	0.9	2.3
SD	102,443	332,279		99,656	83,445
P value within each group	<0.01			NS
P value between groups	NS	0.01

Fold differences are used to summarize the comparison between the ad libitum and calorie-restricted animals after 16 weeks of diet. Note that calorie restriction prevented glomerular enlargement, podocyte hypertrophy, and nonpodocyte glomerular volume expansion. GV/P, glomerular volume per podocyte.