Effects of copper and vitamin B-6 deficiency on taste sensitivity in the rat: a signal detection analysis.

The effects of dietary copper and Vitamin B-6 deficiency on NaCl sensitivity in adult male rats were assessed in separate studies using a double-blind protocol, high-precision gustometry, computer-controlled go/no-go operant procedures and signal detection measures of sensitivity and responsivity. The dietary manipulations reduced plasma copper ion content to 40% of baseline levels in the copper deficient group and plasma 5'-pyridoxalphosphate content to 5% of baseline levels in the Vitamin B-6 deficient group and, as expected, altered hematocrit and hemoglobin levels in both groups. These metabolic changes resulted in increased NaCl preference in the Vitamin B-6 deficient group but did not alter sensitivity or responsivity to NaCl, and similar results were obtained in simple and complex taste discrimination tests. The present results demonstrate that dietary copper and Vitamin B-6 deficiencies do not result in altered taste sensitivity in the adult male rat.