Visual spatial memory is enhanced in female rats (but inhibited in males) by dietary soy phytoestrogens

BMC Neuroscience

Table 1 Brain Phytoestrogen Concentrations (Mean ± SEM) determined in tissues isolated from the frontal cortex and hippocampus (brain structures critical for VSM) along with the amygdala and cerebellum brain regions, by time-resolved fluoroimmunoassay of male rats (pooled by treatment, n = 4 per group).

Phyto-600	daidzein ng/g	genistein ng/g	equol ng/g	total ng/g
Frontal cortex	271.0 (± 29.8)^*	295.5 (± 35.4)^*	705.3 (± 63.4)^*	1,271.8 (± 128.6)^*
Hippocampus	3.4 (± 0.4)	3.1 (± 0.3)	28.5 (± 3.4)	35.0 (± 4.1)
Amygdala	5.5 (± 0.6)^*	9.9 (± 1.1)^*	57.5 (± 5.2)^*	72.9 (± 6.9)^*
Cerebellum	58.8 (± 29.8)^*	126.8 (± 29.8)^*	33.4 (± 29.8)^*	219.0 (± 29.8)^*
Phyto-free	daidzein ng/g	genistein ng/g	equol ng/g	total ng/g
Frontal cortex	2.5 (± 0.3)	1.2 (± 0.1)	23.4 (± 2.8)	27.1 (± 3.2)
Hippocampus	1.4 (± 0.1)	BDL	25.5 (± 3.1)	26.9 (± 3.2)
Amygdala	1.9 (± 0.2)	0.6 (± 0.1)	22.7 (± 2.5)	25.2 (± 2.8)
Cerebellum	2.2 (± 0.2)	0.8 (± 0.1)	20.7 (± 2.1)	23.7 (± 2.4)

Phyto-600 refers to animals exposed to the Phyto-rich diet from 50 days of age until time of sacrifice at 120 days of age. Phyto-free refers to animals exposed to the Phyto-free diet from 50 days of age until sacrifice at 120 days of age. The phytoestrogen content that the animals were exposed to from conception until 50 days of age was approximately 300 ug/g of diet. BDL = below detectable limits (0.5 ng/g) ^*Phyto-600 fed males displayed significantly higher phytoestrogen levels compared to Phyto-free fed males.

ISSN: 1471-2202