Interaction between repeated restraint stress and concomitant midazolam administration on sweet food ingestion in rats

Emotional changes can influence feeding behavior. Previous studies have shown that chronically stressed animals present increased ingestion of sweet food, an effect reversed by a single dose of diazepam administered before testing the animals. The aim of the present study was to evaluate the response of animals chronically treated with midazolam and/or submitted to repeated restraint stress upon the ingestion of sweet food. Male adult Wistar rats were divided into two groups: controls and exposed to restraint 1 h/day, 5 days/week for 40 days. Both groups were subdivided into two other groups treated or not with midazolam (0.06 mg/ml in their drinking water during the 40-day treatment). The animals were placed in a lighted area in the presence of 10 pellets of sweet food (Froot loops(r)). The number of ingested pellets was measured during a period of 3 min, in the presence or absence of fasting. The group chronically treated with midazolam alone presented increased ingestion when compared to control animals (control group: 2.0 +/- 0.44 pellets and midazolam group: 3.60 +/- 0.57 pellets). The group submitted to restraint stress presented an increased ingestion compared to controls (control group: 2.0 +/- 0.44 pellets and stressed group: 4.18 +/- 0.58 pellets). Chronically administered midazolam reduced the ingestion in stressed animals (stressed/water group: 4.18 +/- 0.58 pellets; stressed/midazolam group: 3.2 +/- 0.49 pellets). Thus, repeated stress increases appetite for sweet food independently of hunger and chronic administration of midazolam can decrease this behavioral effect

The use of a new non-verbal test in the evaluation of recent memory

A test for recent memory was developed using non-verbal material. The present report describes a series of experiments conducted to evaluate its reproducibility and the influences of changes in the interval between acquisition and tetrieval, and age and level of instruction, and its sensitivity to the integrity of memory function. A total of 114 subjects participated in 5 experiments. The test of recent memory is reproducible over a period of at least 5 months and can be used with training-testing intervals of 24 to 48h. The performance of the test is affected by age and level of instruction. Moreover, thre memory test is sensitive to differences in the integrity of memory function. Thus, the memory test developed in this study may be used to evaluate the effects of behavioral and/or pharmacological manipulations on recent memory in homogeneous groups of subjects