Table 1.

Cell toxicity in cultured rat hepatocytes exposed to INH with or without RFP

Groups	Cell viability (% of control)		Intracellular glutathione content (μmol per 106 cells)		Albumin secretion (μg per 106 cells)
Culture time	48 h	72 h	48 h	72 h	48 h	72 h
Monolayer culture
Control	100.0±5.8	100.0±8.8	0.43±0.04	0.36±0.03	46.5±15.2	55.0±11.5
INH 0.11 mM	98.7±8.5	95.1±9.5	0.43±0.02	0.35±0.02	45.2±11.5	52.1±12.4
INH 0.11 mM+RFP 12 μM	97.1±4.2	96.3±8.4	0.41±0.05	0.35±0.05	42.1±8.6	57.5±7.6
INH 1.1 mM	94.2±7.2	95.5±5.6	0.41±0.02	0.37±0.02	43.0±9.5	51.2±8.5
INH 1.1 mM+RFP 12 μM	94.8±9.1	93.5±4.5	0.39±0.06	0.32±0.08	42.5±9.6	52.6±9.1
Gel entrapment culture
Control	100.0±7.1	100.0±11.7	0.57±0.04	0.53±0.06	52.0±8.5	77.6±8.6
INH 0.11 mM	93.8±8.9	89.7±5.7*	0.47±0.04*	0.42±0.06*	48.5±7.2	64.5±7.2*
INH 0.11 mM+RFP 12 μM	93.2±10.2	87.5±10.5*	0.42±0.10*	0.40±0.05*	50.6±7.6	60.5±10.5*
INH 1.1 mM	43.7±15.2**	49.0±16.3**	0.25±0.08**	0.21±0.06**	38.2±5.6*	40.0±15.6**
INH 1.1 mM+RFP 12 μM	40.1±9.5**	45.2±6.4**	0.21±0.10**	0.19±0.09**	35.2±9.5*	34.2±11.0**

Abbreviations: INH, isoniazid; RPF, rifampicin.

Data are given as mean±s.d. for each point of three separate experiments; ^*P<0.05 and ^**P<0.01 (compared to controls).