Signal Attenuation as a Rat Model of Obsessive Compulsive Disorder

Abstract

In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus which serves as a feedback cue. This feedback is later attenuated by repeated presentations of the stimulus without food (without the rat emitting the lever-press response). In the next stage, lever-pressing is assessed under extinction conditions (i.e., no food is delivered). At this stage rats display two types of lever-presses, those that are followed by an attempt to collect a reward, and those that are not. The latter are the measure of compulsive-like behavior in the model. A control procedure in which rats do not experience the attenuation of the feedback cue serves to distinguish between the effects of signal attenuation and of extinction. The signal attenuation model is a highly validated model of OCD and differentiates between compulsive-like behaviors and behaviors that are repetitive but not compulsive. In addition the measures collected during the procedure eliminate alternative explanations for differences between the groups being tested, and are quantitative, unbiased and unaffected by inter-experimenter variability. The major disadvantages of this model are the costly equipment, the fact that it requires some technical know-how and the fact that it is time-consuming compared to other models of OCD (11 days). The model may be used for detecting the anti-or pro-compulsive effects of pharmacological and non-pharmacological manipulations and for studying the neural substrate of compulsive behavior.

Smo-Shh Agonist Purmorphamine Prevents Neurobehavioral and Neurochemical Defects in 8-OH-DPAT-Induced Experimental Model of Obsessive-Compulsive Disorder

“…Signal attenuation is a model of OCD in which the rat excessively presses the lever not to collect the reward after signal-attenuation training [60]. This behavior is similar to the unusual repetitive behavior of OCD patients.…”

“…The number of completed excessive-lever-press trials were observed and recorded. The obsessive-compulsiveinduced experimental rats showed more repeated trials than the normal and treated groups [60].…”

Modelos experimentais para o estudo do transtorno obsessivo compulsivo: perspectivas e limitações

“…As maiores descobertas sobre a circuitaria envolvida são decorrentes de trabalhos de neuroimagem funcional, nos quais pesquisadores observaram um possível vínculo entre manifestações clínicas do TOC e mudanças na atividade no circuito córtico-estriado-tálamocortical (CETC) (GRAYBIEL, RAUCH, 2000;ULLRICH et al, 2018) associado aos neurotransmissores glutamato e ácido gama-aminobutírico (GABA). Outros estudos indicam a participação de neurotransmissores como a serotonina (5-hidroxitriptamina -5-HT) e a dopamina (DA) (CORDIOLI, 2014), além do envolvimento de hormônios ovarianos (estrógeno e progesterona) (MITRA et al, 2016), apontados como moduladores do TOC por provocarem ou intensificarem os sintomas em mulheres (GOLTSEKER et al, 2015).…”