Normal 0 MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:Table Normal; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:Times New Roman;} During the first stages of life, the environment and maternal interactions are essential for normal mammalian neuronal maturity and behavior. In fact, it has been demonstrated that disruption of mother-pup interaction during early life exert long-lasting effects on the development of central nervous, endocrine, and immune systems and behavioral responses. The principal aim of our work was to study the consequences of early maternal separation ( EMS ) on adult male and female anxiety. The behaviors was evaluated using the Elavated Plus-Maze (EPM). Separation procedure was carried out in postnatal days 1 to 21 twice daily: three hours in the morning and three hours in the afternoon. As a control group we used animals that stayed with the mother but were manipulated daily for one minute in the morning and in the afternoon. In postnatal day 22, animals were distributed by sex and then kept in standard lab conditions. Behavioral testing in the EPM was performed at 90/95 days of age. All subjects were videotaped. Records included number of entries, time spent in each arm, and the frequency and time stretching, deeping, rearing, and grooming. Our results showed that separated females have more open arm entries and spent more time there, and exhibit more deeping and less grooming compared to females in the control group and males of the experimental and control group. Thus, based on the anxiolytic profile that female rat shows in the EPM, these data suggest that EMS affects differentially male and female adult rats