Failure to demonstrate alterations in gluconeogenesis in growth-retarded weanling rats with dorsomedial hypothalamic lesions.

Bilateral electrolytic lesions were placed in the dorsomedial hypothalamic nuclei (DMN) of weanling male Sprague-Dawley rats. Sham-operated rats served as controls. After 22 days on lab chow and tap water ad libitum, the animals were injected with U-14 C-alanine 0.167 muC/mu moles intraperitoneally (5 muC and 30 mu moles/100 gm body weight) and sacrificed 2 hr later. There was no significant difference, in the incorporation of the label into total lipid, free fatty acids, glycogen, or tissue protein of both liver and diaphragm, between the DMN-lesioned and the sham-operated rats. Similarly, there was no significant difference in the incorporation into plasma glucose or protein. It is concluded that in spite of profound alterations in both ponderal and linear growth and food intake, there is no disruption of normal gluconeogenesis in the weanling rat with DMN lesions.