Table II.
Effects of CPLA on preneoplastic esophageal lesion formation in F344 rats administered with NMBA and euthanized at week 9, 15 or 25.
| Pathological changes in esophageal tissue | ||||||
|---|---|---|---|---|---|---|
|
|
||||||
| Normal | Grade I (dysplasia) | Grade II (preneoplastic lesion) | ||||
|
|
|
|
||||
| Rat treatment | Total n | n | n | Incidence | n | Incidence (%) |
| Week 9 of study | ||||||
| (−) | 5 | 5 | 0 | 0 | 0 | 0 |
| Soya oil | 5 | 5 | 0 | 0 | 0 | 0 |
| NMBA | 15 | 3 | 9 | 9/15 | 3 | 3/15 (20.0) |
| NMBA + CPLA | 15 | 9b | 6 | 6/15 | 0 | 0a |
| Week 15 of study | ||||||
| (−) | 5 | 5 | 0 | 0 | 0 | 0 |
| Soya oil | 5 | 5 | 0 | 0 | 0 | 0 |
| NMBA | 15 | 0 | 8 | 8/15 | 7 | 7/15 (46.7) |
| NMBA + CPLA | 15 | 8b | 7 | 7/15 | 0 | 0a |
| Week 25 of study | ||||||
| (−) | 5 | 5 | 0 | 0 | 0 | 0 |
| Soya oil | 5 | 5 | 0 | 0 | 0 | 0 |
| NMBA | 15 | 0 | 1 | 1/15 | 14 | 14/15 (93.3) |
| NMBA + CPLA | 15 | 0 | 10 | 10/15 | 5 | 5/15 (33.3)a |
a
Significantly lower than NMBA control group at weeks 9, 15 and 25 as determined using a χ2 test (P<0.05).
b
Significantly higher than NMBA control group at weeks 9 and 15 as determined using a χ2 test (P<0.05).
CPLA, lupeal acetate of Cortex periplocae; NMBA, N-nitrosomethyl-benzylamine.