Effect of undernutrition on morphine analgesia, haloperidol catalepsy and pentobarbitone sodium hypnosis in developing new born rats.

ABSTRACT

In the present study, half of the pups of a litter were undernourished by 12 h daily maternal deprivation from day 5 to day 18 postnatal and were subsequently nutritionally rehabilitated. Responses of CNS-acting drugs (morphine analgesia, pentobarbitone sodium hypnosis, haloperidol catalepsy) were studied at the age of day 9, 12 and 18 in maternally deprived and of day 25 in nutritionally rehabilitated new born rats as compared to that of their nourished littermates. The results showed that the response of these CNS-acting drugs was maximum at the age of day 9 postnatal and progressively decreased thereafter as the age of the animal advanced. The responses of these drugs in maternally deprived animals varied on different days of undernourishment as compared to that of their nourished littermates. The responses were significantly less in first half and were significantly more in second half period of undernourishment. The changes observed in the responses of these CNS-acting drugs were directly related to the changes observed in brain serotonin level in maternally deprived and nutritionally rehabilitated new born rats. The present findings suggest that the nature and degree of undernutrition imposed in suckling rats might only produce temporary effects on the response of CNS-actin drugs and on brain serotonin levels which is reversible if undernourished new born rats were nutritionally rehabilitated on an appropriate time of brain development.