title: Interaction of neuropeptidase activities in cortico-limbic regions after acute restraint stress.
abstract: Brain enkephalin, vasopressin and oxytocin are anxiolytic agents involved in the stress response. Acute restraint stress influences certain neuropeptidase activities, such as some enkephalin-degrading peptidases and vasopressinase/oxytocinase, in the medial prefrontal cortex (mPFC), amygdala (AM) or hippocampus (HC), which are involved in this response. Because these regions form a unified circuit and cooperate in their response to stress, it is important to analyze the profile of the regional distribution of these activities as well as their inter-regional model of interaction in this circuit. Regarding the regional study, although most activities showed a marked predominance of the AM over the HC and mPFC, both in control and stressed animals, enkephalin-degrading activity, assayed as membrane-bound alanyl aminopeptidase activity, showed a change after stress, increasing in the HC and decreasing in the AM. The correlational study in controls indicated essentially a positive interaction between the mPFC and AM. In marked contrast, there was a highly significant change in the functional status of this circuit after stress, showing mainly a positive correlation between the mPFC and HC and between the AM and HC. The existence of correlations does not demonstrate a direct relationship between regions. However, reasons for such strong associations after restraint stress should be examined. The present study may indicate a connection between neuropeptidase activities and their corresponding neuropeptidergic substrates due to significant changes in the functional status of the cortico-limbic circuit after restraint stress.
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Hernández
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Prieto
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Segarra
authors.affiliation: Cardiovascular and Metabolic Syndrome Adviser, Rue es Planches 5, 2842 Rossemaison, Switzerland.
authors.forename: Marc
authors.initials: M
authors.lastname: de Gasparo
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
authors.forename: Rosemary
authors.initials: R
authors.lastname: Wangensteen
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Villarejo
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Banegas
authors.affiliation: Instituto de Neurociencia 'Federico Oloriz', University of Granada, Granada, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Vives
authors.affiliation: Department of Inorganic and Organic Chemistry, University of Jaen, Spain.
authors.forename: Justo
authors.initials: J
authors.lastname: Cobo
authors.affiliation: Unit of Physiology, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain. Electronic address: msanchez@ujaen.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Ramírez-Sánchez
mesh_terms: D000626:Aminopeptidases / Q000032:analysis / Q000378:metabolism*; D000679:Amygdala / Q000201:enzymology*; D000818:Animals; D014151:Anti-Anxiety Agents / Q000378:metabolism; D004745:Enkephalins / Q000378:metabolism; D006624:Hippocampus / Q000201:enzymology*; D008297:Male; D009434:Neural Pathways / Q000201:enzymology; D010121:Oxytocin / Q000378:metabolism; D017397:Prefrontal Cortex / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000201:enzymology*; D014667:Vasopressins / Q000378:metabolism
chemical_list: D014151:Anti-Anxiety Agents; D004745:Enkephalins; D014667:Vasopressins; D010121:Oxytocin; D000626:Aminopeptidases
keywords: Amygdala; Enkephalin-degrading peptidases; Hippocampus; Medial prefrontal cortex; Oxytocinase; Vasopressinase