Inhibition of fluorescein accumulation by various xenobiotic compounds
| . | . | Uptake rate . | . | . | |
|---|---|---|---|---|---|
| Compound . | Concentration (mmol l-1) . | Controla . | Treatmentb . | N . | |
| Insecticides | |||||
| Malathion | 0.5 | 94.2±3.4 | 85.0±10.6 | 6 | |
| Permethrin | 0.5 | 89.1±1.8 | 76.9±5.1* | 6 | |
| Chlorpyrifos | 0.1 | 95.2±4.7 | 90.8±9.0 | 7 | |
| Chlorpyrifos | 0.5 | 108.3±4.6 | 97.4±13.5 | 4 | |
| Carbaryl | 0.25 | 95.2±3.1 | 75.4±5.1* | 6 | |
| Metabolites | |||||
| Malathion oxon | 0.5 | 86.3±1.4 | 88.9±5.4 | 6 | |
| Malathion monocarboxylic acid (isomer mixture)(MMA) | 0.5 | 91.3±2.7 | 74.5±3.2* | 6 | |
| MMA | 1 | 93.6±4.8 | 38.9±7.5* | 6 | |
| 3-Phenoxybenzoic acid (PBA) | 0.5 | 93.6±3.3 | 30.2±12.3* | 9 | |
| Chlorpyrifos oxon | 0.1 | 103.1±5.8 | 121.5±12.1 | 5 | |
| Chlorpyrifos oxon | 0.5 | 99.9±7.2 | 72.6±16.6 | 4 | |
| Herbicides | |||||
| 2,4-Dichlorophenoxyacetic acid (2,4-D) | 1 | 94.0±5.1 | 50.4±9.6* | 6 | |
| 4-(2,4-Dichlorophenoxy)-butyric acid (2,4-DB) | 1 | 95.0±4.3 | -19.4±8.3* | 7 | |
| Plant alkaloids | |||||
| Nicotine | 0.5 | 100.0±12.4 | 77.6±9.3 | 3 | |
| Atropine | 1 | 98.4±4.3 | 100.4±10.8 | 6 | |
| Quinine | 1 | 96.0±4.9 | 45.0±12.6* | 6 | |
| . | . | Uptake rate . | . | . | |
|---|---|---|---|---|---|
| Compound . | Concentration (mmol l-1) . | Controla . | Treatmentb . | N . | |
| Insecticides | |||||
| Malathion | 0.5 | 94.2±3.4 | 85.0±10.6 | 6 | |
| Permethrin | 0.5 | 89.1±1.8 | 76.9±5.1* | 6 | |
| Chlorpyrifos | 0.1 | 95.2±4.7 | 90.8±9.0 | 7 | |
| Chlorpyrifos | 0.5 | 108.3±4.6 | 97.4±13.5 | 4 | |
| Carbaryl | 0.25 | 95.2±3.1 | 75.4±5.1* | 6 | |
| Metabolites | |||||
| Malathion oxon | 0.5 | 86.3±1.4 | 88.9±5.4 | 6 | |
| Malathion monocarboxylic acid (isomer mixture)(MMA) | 0.5 | 91.3±2.7 | 74.5±3.2* | 6 | |
| MMA | 1 | 93.6±4.8 | 38.9±7.5* | 6 | |
| 3-Phenoxybenzoic acid (PBA) | 0.5 | 93.6±3.3 | 30.2±12.3* | 9 | |
| Chlorpyrifos oxon | 0.1 | 103.1±5.8 | 121.5±12.1 | 5 | |
| Chlorpyrifos oxon | 0.5 | 99.9±7.2 | 72.6±16.6 | 4 | |
| Herbicides | |||||
| 2,4-Dichlorophenoxyacetic acid (2,4-D) | 1 | 94.0±5.1 | 50.4±9.6* | 6 | |
| 4-(2,4-Dichlorophenoxy)-butyric acid (2,4-DB) | 1 | 95.0±4.3 | -19.4±8.3* | 7 | |
| Plant alkaloids | |||||
| Nicotine | 0.5 | 100.0±12.4 | 77.6±9.3 | 3 | |
| Atropine | 1 | 98.4±4.3 | 100.4±10.8 | 6 | |
| Quinine | 1 | 96.0±4.9 | 45.0±12.6* | 6 | |
All values are means ±s.e.m.N = number of tubules per sample. Negative values represent trials in which the introduction of test compound resulted in a net FL efflux from the tubule (a decrease in fluorescence).
Control uptake rate (in absence of inhibitor) is the rate during the second measurement period (no inhibitor) expressed as percent of uptake measured in the first measurement period. See text for details
Treatment uptake rate (in presence of inhibitor) during second measurement period (inhibitor present) expressed as percent of uptake measured in the first measurement period
Change in uptake rate in presence of inhibitor significantly different from change in uptake rate in absence of inhibitor; P<0.05, paired t-test