ACUTE AND LONG-TERM BEHAVIORAL-CORRELATES OF UNDERWATER TRAUMA - POTENTIAL RELEVANCE TO STRESS AND POSTSTRESS SYNDROMES

As a consequence of a brief but significantly extreme stressor, an ind ividual will experience a stress response, which may sometimes develop into Acute Stress Disorder (ASD) or Post-Traumatic Stress Disorder (P TSD). Though a rat model for ASD and PTSD is not expected to encompass the richness and complexity of the disorders in humans, it will enabl e the study of the common underlying mechanisms that generate the diso rders, the study of pre-trauma etiological aspects of the disorders an d the screening of drugs with potential relevance to the treatment of the disorders. One well-documented aspect of PTSD is the enhancing inf luence of contextual elements on the appearance of symptoms of the pos t-stress trauma. To exploit this effect, we have chosen to assess the effects of an underwater trauma in the Morris water maze since the eff ects of such trauma on memory and attention can be later evaluated in the context of the trauma. At both 1 h and 3 weeks after the trauma, s ignificant behavioral deficits were observed in the water maze. The ef fects of the underwater trauma on the performance of rats in the water maze were context specific. Underwater trauma in a different (out-of- context) water container had no effects on the ability of rats to perf orm a spatial memory task in the water maze. An elevated level of anxi ety was found in the plus maze test, independently of whether the trau ma was performed in the water maze or in a different (out-of-context) water container. The results indicate that a within-context underwater trauma has both acute and lasting behavioral consequences which can b e assessed using a spatial memory test in the context of the trauma. T he results are discussed in relation to their relevance to stress and PTSD. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.