Animal model of anxiety: effect of chronic diazepam treatment in the genetically hypertensive rats of Koletsky type and in the rats of Wistar strain.

: Experiments were performed in the adult normotensive rats of Wistar strain in the genetically hypertensive rats of Koltsky type. Diazepam at the dose of 1 mg/kg was applied for five days. The last two days of diazepam treatment the behavior of the animals was traced in holeboard and in the elevated plus-maze. In the control animals the genetically hypertensive rats of both sexes show elevated locomotor-exploratory activity in holeboard in both sessions, genetically hypertensive females show highest degree of directed exploration in holeboard when compared with the other groups of rats; in the elevated plus-maze the normotensive rats of both sexes show lower aversion towards open space and height in elevated plus-maze relative to genetically hypertensive rats. Diazepam only in the genetically hypertensive females increases in the second session locomotor-exploratory activity and reduced the inter-session habituation of the mentioned activity. Directed exploratory activity in holeboard was by diazepam treatment elevated predominantly in the genetically hypertensive rats. In the genetically hypertensive females diazepam caused inter-session sensitization in directed exploration. Considering the number of entries in centre and in open arms of the elevated plus-maze, diazepam in both strains irrespective of sex and session caused increase. Taking into account time spent in centre and in open arms of the elevated plus-maze, the strain dependent effect of diazepam is apparent, i.e., statistical significance of its "anxiolytic" effect was attained only in the genetically hypertensive rats.