Septal destruction in infant rats and the ontogeny of drinking behaviors

Parabrachial nuclei damage in infant rats produces residual deficits in gustatory preferences/aversions and sodium appetite

Ten-day-old rats sustained bilateral electrolytic lesions of the parabrachial nuclei in the pons (PBN). Growth measures and tests of sensorimotor, feeding and drinking behaviors, sodium appetite, and gustatory capacities were made between ages 1 and 150 days. PBN rats displayed a transient period of attenuated suckling, as evidenced by body weight loss. When tested soon after weaning, PBN rats were hyperdipsic in response to cellular dehydration and during food deprivation. This effect, however, was temporary. When tested as adults, PBN rats were hypodipsic in response to extracellular fluid volume depletion, they displayed alterations in sodium appetite, showed "exaggerated" preferences and aversions to saccharin and NaCl solutions, and they displayed attenuated quinine aversions. These results are generally similar to the behaviors of rats sustaining more central gustatory pathway lesions as adults. The functional significance of the PBN in the developing rat for preference/aversion and sodium appetite behaviors are discussed.

Comparison between the behavioural effects of septal and hippocampal lesions: a review

The literature on the behavioural effects of septal and hippocampal lesions is classified according to behavioural paradigm. The effects of the two kinds of lesion are summarized and compared to each other. A 'septo-hippocampal syndrome,' consisting of the effects common to both lesions, is delineated, and divergences between the effects of the two lesions are noted.