Enhanced responses of the chorda tympani nerve to sugars in the ventromedial hypothalamic obese rat.

Sweet taste sensitivity in obese rats with lesions of the ventromedial hypothalamus (VMH) was studied by examining chorda tympani nerve responses to various taste stimuli including sugars. In the early progressive phase of obesity (2 wk after creating VMH lesions), there was no significant difference in the nerve responses to any taste stimulus between sham-operated and VMH-lesioned rats. In contrast, in the late phase of obesity (15-18 wk after VMH lesions), the magnitude of responses to sugars (except for fructose) was prominently greater than that in age-matched controls.

Proliferative ability and alkaline phosphatase activity with in vivo cellular aging in human pulp cells.

Little is known about the effect of aging on characteristic functions of pulp cells. When damaged pulp is recovered and mineralized tissue is formed to protect remaining pulp tissue, the general responses of pulp tissue after adequate stimuli (pulp cell proliferation and activation of alkaline phosphatase [ALPase]) are thought to be essential. In this study, we compared proliferative ability and ALPase activity between cultures of human pulp (HP) cells obtained from young and aged donors.