Kupffer cells promote lead nitrate-induced hepatocyte apoptosis via oxidative stress

Comparative Hepatology

Table 6 Evaluation of apoptosis versus necrosis in HepG2 cultures incubated with 10 mM Pb(NO₃)₂, Pb(C₂H₃O₃)₂ or KNO₃ and with conditioned medium from Kupffer cells incubated with10 mM Pb(NO₃)₂ for 24 hours.*

Treatments	6 hours		8 hours		16 hours		24 hours		48 hours
	Necrosis	Apoptosis	Necrosis	Apoptosis	Necrosis	Apoptosis	Necrosis	Apoptosis	Necrosis	Apoptosis
Control	2.00	0.80	2.05	0.75	2.50	1.20	2.70	3.51	3.06	4.01
Pb(NO₃)₂	1.80	0.90	2.05	1.17	2.84	1.15	13.73^	4.35	25.00^	9.20
Pb(C₂H₃O₂)₂	4.50^	2.10	18.90^	1.80	35.30^	3.10	81.03^	7.50^	92.60^	15.20^
KNO₃	1.42	0.18	1.20	0.53	2.69	0.70	7.71	1.19	15.30^	12.58^
C.M. 1	0.80	1.10	2.10	1.50	2.50	2.00	3.80	3.20	4.10	3.80
C.M. 2	1.70	3.10^	3.20	4.50^	2.80	10.10^	3.20	18.50^	3.80	25.30^
C.M. 3	0.90	2.00	1.80	3.10	1.90	2.30	2.50	7.10	2.90	4.20

* Control animals were injected with saline. Apoptosis and necrosis were detected on slides of haematoxylin-eosin stained cells counting at least 150 cells in at least 10 randomly selected fields. C.M. 1 = conditioned medium collected from normal untreated Kupffer cell cultures. C.M. 2 = conditioned medium collected from Kupffer cell cultures incubated for 24 hours with Pb(NO₃)₂ (10 mM). C.M. 3 = conditioned medium collected from Kupffer cell cultures incubated for 24 h with KNO₃ (10 mM). Data are given as percentages. Standard deviations did not exceed 5%. ^Significantly different in relation to Control (p < 0.05).