Table 4.
Comparison of serum gastrin, gastric pH, and gastric neuroendocrine cell hyperplasia and neoplasia in female F344 rats administered Methyleugenol.a
| 14-week studyb (female F344/N rats) | 2-year studyc (female F344/N rats) | |||||
|---|---|---|---|---|---|---|
| Methyleugenol dose (mg/kg/day) | Serum gastrin: 30 days (n = 10) | Serum gastrin: 90 days (n = 10) | Glandular stomach pH: 30 days (n = 10) | Glandular stomach pH: 90 days (n = 10) | Glandular stomach: Neuroendocrine cell hyperplasia (n = 50) | Glandular stomach: Benign or malignant neuroendocrine tumor (n = 50) |
| 0 | 62 ± 7 | 41 ± 3 | 2.2 ± 0.1 | 2.2 ± 0.3 | 0 | 0 |
| 37 | 25 ± 4d | 46 ± 3 | 2.4 ± 0.3 | 1.8 ± 0.1 | 5 | 1 |
| 75 | 22 ± 2d | 60 ± 6 | 1.7 ± 0.1 | 2.2 ± 0.2 | 11 | 25 |
| 150 | 57 ± 14 | 88 ± 11d | 1.9 ± 0.2 | 2.0 ± 0.2 | 9 | 34 |
| 300 | 127 ± 23d | 409 ± 68c | 1.6 ± 0.2c | 3.1 ± 0.5c | 3 | 41 |
A simplified table to illustrate the interrelationship between serum gastrin, gastric pH, and neuroendocrine cell hyperplasia or neoplasia of the glandular stomach.
a
National Toxicology Program—Technical Report 391 (2000).
b
The 30/90 day investigative study was conducted only in female F344 and male B6C3F1 mice. Data are presented as mean ± standard error.
c
The 2-year carcinogenesis bioassay was conducted in both genders of F344 rats and B6C3F1 mice. Neuroendocrine tumors were observed in rats of both genders and male mice.
d
Significantly different from controls.