INTRODUCTION: MOTOR STEREOTYPIES ARE RHYTHMIC, REPETITIVE, INVOLUNTARY MOVEMENTS THAT CAN OCCUR IN ASSOCIATION WITH SOME NEUROPSYCHIATRIC DISORDERS. TYPICAL MOVEMENTS INCLUDE REPEATED, RECURRENT, RAISING AND LOWERING OF THE ARMS AND LEGS, FLAPPING, WAVING AND OTHER FORMS. THE TYPICAL AGE AT ONSET FOR CHILDHOOD STEREOTYPIES IS LESS THAN 2 YEARS. THESE MOVEMENTS COULD BE MISTAKES WITH EPILEPTIC SEIZURES IN INFANTS...

Introduction: Improvement of negative symptoms of psychosis by atypical drugs has been related to the medial prefrontal cortex (mPFC). mPFC is a heterogeneous area (prelimbic, infralimbic and anterior cingulated) with particular inputs and outputs with subcortical regions. mPFC is involved in the induction of locomotor hyperactivity, and clozapine inhibits this behavior. But role of mPFC in apomorphine-induced STEREOTYPY behaviors is unclear. STEREOTYPY behaviors induced by apomorphine, a dopamine agonist, in animals are as animal In this work we studied stereotyped behaviors induced by APO injected in different subregions of mPFC, to show that the role of each subarea of mPFC in STEREOTYPY behaviors is different.Methods: We implanted cannula in prelimbic, infralimbic or anterior cingulated areas of mPFC. APO in five doses was microinjected, and then behaviors were recorded.Results: There was a significant difference between three subareas. Sniffing, chewing and licking showed significant increase when APO was injected in the anterior cingulated, rearing and climbing with injection in the infralimbic, and yawing with injection in the prelimbic area showed significant increase (P<0.05).Conclusion: These data could be discussed considering the connections of mPFC with limbic and striatum and also an inverse relationship between DA transmission in the cortical and subcortical dopaminergic systems.

The present study was performed to evaluate the effect of morphine sensitization on behavioural responses and mRNA expression of NMDA receptor subunits (NR1 and NR2) in the certain areas of male rat brain (striatum, prefrontal cortex, hippocampus, hypothalamus and amygdala). At first behavioral sensitization (in animal models such as locomotion, oral STEREOTYPY and state dependent memory) were measured in the presence or absence of MK801 (NMDA receptor antagonist). Our results showed that chronic morphine treatment followed by 7 days (but not 24 h) wash out period produced morphine sensitization. The exception was morphine 2.5 mg/kg induced memory retention in morphine state dependent memory which was augmented after both 24 h and 7 days wash out period. Furthermore in morphine sensitized animals, administration of MK801 (0.1 and 0.25 mg/kg), 30 min before test dose of morphine (5 mg/kg) failed to attenuate the locomotion and oral STEREOTYPY. Whereas, higher dose of MK801 (0.25 mg/kg) could decrease memory retention induced by the test doses of morphine (2.5 mg/kg) in state dependent memory test. This effect may be due to intrinsic motor enhancer property of MK801. The results of quantitative real time RT-PCR clearly indicated that morphine sensitization increased the expression of the mRNA for receptor subunits in the amygdala [NR1 (by 104%) and NR2 (by 85)], while the other areas of the brain were unaffected. In summary it can be concluded that the elevation of NMDA receptor subunits expression may be associated with morphine induced behavioral sensitization. However MK801 failed to abolish morphine sensitization in its expression phase.