Intravermis cerebellar microinjection effects of histamine in the object recognition memory in mice

Abstract

Histamine is a biogenic amine found in peripheral tissues and in the Central Nervous System (CNS). Cell bodies of histaminergic neurons emerge from the hypothalamic tuberomammillary nucleus and send projections to CNS structures, including the cerebellum. Studies show the effects of the histaminergic system on the cerebellum in motor and non-motor functions. However, the role of cerebellar histamine in object recognition memory is not known. Therefore, the present study will investigate the effects of different doses of histamine intravermis cerebellar microinjections in the declarative memory in rodents, resorting of the novel object recognition task (NOR). The experiment will be performed in male mice (Swiss Albino) weighing from 25 to 35 g. By means of stereotactic surgery, the animals will be implanted with a 7 mm length guide cannula in the cerebellar vermis. Two days after surgery, the mice will go through habituation, followed by familiarization and microinjection 24 hours later, and object recognition test 72 hours later. The injection site will be confirmed by histological analysis. The statistical analysis will consist of the homogeneity test and variance analysis (ANOVA), followed by a posthoc test fitting to the experimental design. (AU)