Operant self-administration of alcohol and sucrose in adolescent rats

PAUTASSI RM; MOLINA JC; SPEAR, LP; SPEAR NE

Huerta Grande

Congreso; IRCN, First Joint Meeting of the Argentine Society for Neurosciences (SAN) and the Argentine Workshop in Neurosciences (TAN); 2009

Argentine Society for Neurosciences (SAN) and the Argentine Workshop in Neurosciences (TAN)

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} p {mso-margin-top-alt:auto; margin-right:0in; mso-margin-bottom-alt:auto; margin-left:0in; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> OPERANT SELF-ADMINISTRATION OF ALCOHOL AND SUCROSE IN ADOLESCENT RATS   Pautassi RM, Molina JC, Spear LP, Spear NE State University of New York at Binghamton, Center for Developmental Psychobiology, Binghamton, NY, 13902-6000. Instituto de Investigaciones Medicas M. y M. Ferreyra, Friuli 2434, Córdoba, CP5016, República Argentina   Alcohol exposure during adolescence is associated with later alcohol affinity. It is therefore important to analyze ethanol consumption patterns during adolescence. In the rat, this has been assessed by two-bottle choice or forced intake tests. There have been far fewer attempts, however, to analyze ethanol reinforcement in adolescent rats through operant tasks. This may be due to a lack of operant behavioral techniques that can be fully implemented within the short timeframe of adolescence. This study examined operant self-administration of alcohol or sucrose in male and female adolescent Sprague-Dawley rats. On postnatal day (PD) 30, the rats (n=58) were surgically implanted with cannulae made out of polyethylene tubing. These devices permitted intraoral infusion of the reinforcers. During PDs 32-34, the rats were placed in operant chambers equipped with a single hole for nose-poking. The experimental (paired) rats received an intraoral infusion of ethanol (3-5%, increasing 1% each day; 5 ul) or sucrose (5%, 30 ul) after each nose-poke. Daily trials lasted for 30 min; yoked controls were employed for each experimental condition. The data analysis indicated significantly more daily target responses in experimental animals that in yoked controls (Xs=41.71 and 6.09, respectively). Operant responses per session were similar across males and females but significantly higher in sucrose-reinforced animals than in paired rats given ethanol (Xs=55.93 and 28.79, respectively). Average ethanol intake per session was 0.20 g/kg. The experiment indicates that, without the need for a long training or an initiation phase, ethanol supports operant self-administration in adolescent rats, although at a much lower rate than does sucrose.