Effect of neurotensin on regional cerebral glucose utilization in cold water-restrained rats

Neurotensin (NT), given intracerebroventricularly (icv), attenuates cold water restraint (CWR)-induced gastric mucosal injury; however, it is not clear which brain nuclear group or groups are involved. These studies tested the hypothesis that neuronal function, as measured by regional cerebral metabolic rate for glucose (rCMRGlc), is altered by icv NT with or without CWR. CWR resulted in a reduced global glucose utilization of 72 and 65% in control and NT-treated rats, respectively. NT, given icv, protected against ulcer formation induced by CWR. In those rats given NT icv, rCMRGlc was elevated significantly in amygdala, nucleus accumbens, substantia nigra, tuberculum olfactrium, hypothalamus, and cerebellum compared with CWR rats without NT pretreatment. This rCMRGlc increase was observed in both unstressed and stressed rats given NT icv in the nucleus accumbens and amygdala. These observations suggest that the nucleus accumbens and amygdala, both components of the mesolimbic dopamine system, are involved in the central action of NT on the gastric mucosa.