Learn More
In an attempt to study the possible role of active sleep in brain development, male rats were injected twice daily with chlorimipramine, a potent monoamine reuptake blocker, from 1 week to 3 weeks of postnatal age. AS was reduced to less than 10% of total sleep time, the level found in mature rats. Most of the AS reduction was compensated for by quiet sleep(More)
The relative contribution of organizing and activating effects of sex hormones to the establishment of gender differences in behaviour is still unclear. In a group of 35 female-to-male transsexuals and a group of 15 male-to-female transsexuals a large battery of tests on aggression, sexual motivation and cognitive functioning was administered twice: shortly(More)
The present experiment investigated the effects of exposure to inescapable shocks (IS) on subsequent behavior in an elevated plus-maze and on shuttlebox-escape performance in male and female rats. In the elevated plus-maze, exposure to IS resulted in suppression of "total number of arm entries" and "rearings" in males but not in females. In addition "time(More)
Recently, the vasopressin (AVP) innervation in the rat brain was shown to be restored in senescent rats following long-term testosterone administration. In order to investigate whether this restoration is accompanied by an improvement in learning and memory, both sham- and testosterone-treated young (4.5 months), middle-aged (20 months), and aged (31(More)
Male and female Wistar rats were exposed to different radial-maze procedures to determine whether or not behavioral differences would be observed. They were allowed free access to all arms of the maze in the first experimental condition, while they were confined between choices to the central platform for 1 and 15 sec during the second and third(More)
Discrete bilateral lesions in the SDN-POA of sexually naive adult male rats were found to decrease the number of animals ejaculating and/or to increase latencies to the first mount, intromission and ejaculation. The deleterious effects of the lesions disappeared after 4 tests for sexual behavior but were reinstated when the males were tested under(More)
The present study investigated 1) the importance of the aromatization process during the perinatal period for the development of the sexually dimorphic nucleus in the preoptic area of the hypothalamus (SDN-POA) of male rats, and 2) the relationship between SDN-POA volume and parameters of masculinization in male rats that were treated perinatally with the(More)
In order to test the hypothesis that active sleep (AS) is important for the normal development of the central nervous system, 3 different deprivation methods were applied to male Wistar rat pups during the first month of life. Daily injection of clomipramine from 8 to 21 days of age reduced the high level of AS to less than the adult value throughout most(More)
Bilateral lesions were made, confined to the orbitofrontal part of the prefrontal cortex (OF) of male WEZOB rats at 3 different ages (30, 45 and 60 days) and behavioural changes were studied in adulthood. In a test situation for intermale aggression OF-lesioned animals showed a higher level of aggression than their control-operated opponents. Such changes(More)