Effect of the removal of olfactory bulbs upon hyperphagia and obesity induced in rats by V.M.H. Lesion

Abstract

The effect of a combination of a VMH lesion and of the removal of olfactory bulbs has been tested in rats, in an attempt to clarify the role of the overresponsiveness to the oro-sensory action of foods in hyperphagia and obesity developed after this lesion and, more generally, of olfactory cues in the control of food intake. A bilateral bulbectomy occurring either at the beginning of a second dynamic phase after starvation, or when the first static phase had been reached, induced a rebound of hyperphagia and weight gain leading to a higher level of the static phase of the obesity. This unexpected result is discussed with respect to the mechanisms of finickiness and to the role of oro-sensory afferents in the control of a constant daily intake.