Unilateral but not bilateral olfactory bulbectomy inhibits body weight gain in hamsters.

The relation of the olfactory bulbs and photoperiod to the regulation of body weight was studied in male golden hamsters. Animals underwent sham operation, bilateral olfactory bulbectomy, or unilateral bulbectomy. They were left on long photoperiod for 5 weeks and then were transferred to short photoperiod for 11 weeks. The unilaterally olfactory bulbectomized hamsters gained less weight on long or short photoperiod than the sham operated group, while the bilaterally bulbectomized hamsters gained at least as much weight as the sham group. Thus, we report the novel finding that unilateral but not bilateral olfactory bulbectomy reduces body weight gain in male golden hamsters.