Social and emotional behaviour in rats after perinatal treatment with tranylcypromine

Serotonin (5-hidroksitriptamin, 5-HT) je biološki aktivan amin. Nalazi se u mozgu i na periferiji gdje vrši različite fiziološke uloge, a također kontrolira razvoj mozga. Promjene u sustavu koji regulira metabolizam i funkciju 5-HT mogle bi predstavljati jednu od mogućih bioloških podloga poremećaja ponašanja u koje spada i autizam. Smatra se da visoka razina 5-HT u krvi, u doba fetalnog i ranog postanatalnog razvoja, može inhibirati rast i razvoj 5-HT neurona i tako dovesti do anatomskih i funkcionalnih promjena u mozgu. Kako bi se ispitale posljedice visoke razine 5-HT u krvi u doba perinatalnog razvoja na središnji odjeljak 5-HT, štakori su bili tretirani inhibitorom monoamin oksidaze (MAOI), tranilciprominom (TCP, 2mg/kg), od 13. embrionalnog do 21. postnatalnog dana života. U ovom radu smo istražili posljedice perinatalnog tretmana s MAOI na kognitivno, socijalno i emotivno ponašanje štakora. Eksperimentalne štakore tretirane TCP-om i kontrolne štakore tretirane fiziološkom otopinom podvrgnuli smo bateriji testova ponašanja kojima smo redom ispitali: učenje i kognitivnu rigidnost, lokomotorno ponašanje, anksioznost i eksploratorno ponašanje, socijabilnost te reakciju i habituaciju na opetovani zvučni podražaj. Skupina tretirana TCP-om pokazala je smanjenu razinu anksioznosti i kognitivne rigidnosti te povećanu razinu eksploratornog ponašanja i socijabilnosti u odnosu na kontrolnu skupinu. Razina lokomotornog gibanja nije se razlikovala između skupina. Rezultati pokazuju da je perinatalni tretman inhibitorom razgradnje serotonina utjecao na ponašanja regulirana serotoninom, što ukazuje na promjene u središnjem odjeljku 5-HT nastale tijekom razvoja mozga.Serotonin (5-hydroxytryptamine, 5-HT) is a biologically active amine present in both brain and peripheral tissues where it serves different physiological functions and it also regulates brain development. Disruption of 5-HT metabolic pathway or impairments in its function could represent a base for different behavioral disorders including autism. During prenatal and early postnatal development, high concentrations of serotonin in blood could inhibit 5HT neuronal growth and differentiation and cause anatomical and functional changes in brain. To examine consequences of high blood 5-HT concentrations during perinatal development, rats were treated with monoamine oxidase inhibitor (MAOI), TCP (tranylcypromine, 2mg/kg) from 13th gestational day until 21st postnatal day. In this study we explored consequences of the mentioned perinatal treatment on cognitive, social and emotional behavior in rats. Experimental group (treated with TCP) and control group (treated with saline solution) of rats were submitted to the battery of tests. We examined learning and cognitive rigidity, locomotor activity, anxiety and exploratory behavior, sociability, and reaction and habituation to repeated high-frequency sound. Experimental group displayed significantly lower level of anxiety and cognitive rigidity, and showed higher sociability and exploratory behavior. Levels of locomotor activity did not differ between the groups. These results show that the treatment with TCP has influenced 5-HT-regulated behaviors, and indicate changes in the central 5-HT compartment that occurred during brain development