Table 1.

Effect of short-term fixation on transition metal concentrations in the amygdala reported in the literature

Study and method	[Iron] control	[Iron] AD	[Zinc] control	[Zinc] AD	[Copper] control	[Copper] AD
Fixed tissue	18.9 ± 5.3	38.8 ± 9.4	22.6 ± 2.8	51.4 ± 11.0	4.4 ± 1.5	19.3 ± 6.3
Lovell et al. 1998—micro-PIXE, 24 h formalin exposure	N = 5	N = 9	N = 5	N = 9	N = 5	N = 9
Never-fixed tissue	49.2 ± 3.3	65.5 ± 3.8	14.5 ± 0.5	18.2 ± 0.7	4.1 ± 0.3	2.7 ± 0.3
	N = 56	N = 101	N = 69	N = 119	N = 11	N = 10
Thompson 1988—INAA	48.9 ± 3.0	60.6 ± 4.9	14.1 ± 0.5	17.0 ± 0.8	–	–
Samudralwar 1995—INAA	50.8 ± 3.7	70.8 ± 4.0	16.7 ± 0.5	21.4 ± 0.5	–	–
Deibel 1996—INAA	48.6 ± 2.2	70.8 ± 6.4	15.2 ± 0.6	19.8 ± 1.0	4.1 ± 0.3	2.7 ± 0.3
Cornett 1998—INAA	49.0 ± 4.0	64.0 ± 3.0	13.6 ± 0.5	17.6 ± 0.6	–	–
Rulon 2000—AA	–	–	15.7 ± 0.5	16.6 ± 1.0	–	–
Percent change (Two-tailed t-test)	−61% P <0.0001	−41% P <0.0001	+56% P <0.0001	+182% P <0.0001	+7.3% P = 0.52	+615% P <0.0001

All six studies listed were published from the same laboratory at the University of Kentucky. One study analyzed fixed tissue; the others analyzed never-fixed tissue – all used quantitative analytical methods. The never-fixed results are pooled in the second row and listed individually below. Measurements represent microgram metal per gram tissue, wet weight (results from Deibel et al. 1996 were converted from dry weight measurements to wet weight). Errors listed are standard deviation

AD Alzheimer’s disease, PIXE particle induced x-ray emission, INAA instrumental neutron activation analysis