Prostaglandins, Leukotrienes and Essential Fatty Acids 72 (2005) 357–362 N-6 polynsaturated fatty acids confer hemodynamic stability in an experimental model of multiple trauma Nicolas Efstathopoulos a , Efstathios Bathrellos a , Evangelos J. Giamarellos-Bourboulis b,Ã , John Lazarettos a , Apostolos Papalois c , Paraskevi Grecka b , Vassilios Nikolaou a a 2nd Department of Orthopaedics, University of Athens, Medical School, Greece b 4th Department of Internal Medicine, University of Athens, Medical School, ATTIKON University Hospital, 1 Rimini Street, 124 64 Athens, Greece c Laboratory of Experimental Surgery, ‘‘ELPEN’’ Pharmaceuticals, Greece Received 11 July 2004; accepted 3 February 2005 Abstract Immunonutrition with diets enriched in polyunsaturated fatty acids (PUFAs) are becoming mandatory for multiple trauma patients. Solutions containing single n-6 PUFAs were administered intravenously in an experimental model of trauma. Thirty-five rabbits were studied; 13 controls; 10 administered gamma-linolenic acid (GLA) 30 min after fracture of the right femor; and 12 arachidonic acid (AA). Systolic, diastolic and mean arterial pressures and heart rate were recorded; serum levels of tumor necrosis factor-alpha (TNFa), malondialdehyde (MDA) and nitrate were estimated before and after therapy. Mean survival of controls, of animals treated with GLA and of animals treated with AA was 0.80, 1.41 and 3.60 days, respectively. Administration of PUFAs induced higher levels of blood pressure; that of AA decreased serum TNFa and tissue bacterial load compared to controls. Intravenous administration of n-6 PUFAs conferred hemodynamic stability and increased survival in a model of trauma rendering further research mandatory. r 2005 Elsevier Ltd. All rights reserved. 1. Introduction Multiple trauma is a major cause of the systemic inflammatory response syndrome (SIRS) often accompa- nied by rapid deterioration of the patient and subsequent death [1]. On that concept, patients with multiple injuries are often candidates for immunotherapy. Polyunsaturated fatty acids (PUFAs) have been proposed for immunother- apy, based on results of both animal studies and clinical studies [2]. PUFAs of the n-3 series were found to decrease secretion of pro-inflammatory cytokines and to ameliorate function of the NK cells [3]. Studies performed thus far involved either feeding of animals with diets enriched in n- 3 PUFAs before the induction of the acute inflammatory state of trauma or the parenteral administration of emulsions enriched in n-3 PUFAs in patients [3,4]. No study exists, to our knowledge, attempting the adminis- tration of a solution of one single PUFA. Solutions containing single gamma-linolenic acid (C 18:3 , GLA) and arachidonic acid (C 20:4 , AA) have been prepared by our study group; when administered intravenously in healthy rabbits they caused a transient increase of serum peroxides [5]. Owing to their latter effect on serum oxidant status, these solutions were administered in an experimental model of severe injury in rabbits to document their probable effect on overall survival and vital signs of animals. 2. Animals and methods 2.1. Animals A total of 35 white New Zealand male rabbits of a mean (7SD) weight of 3.3970.33 kg were studied. The ARTICLE IN PRESS www.elsevier.com/locate/plefa 0952-3278/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.plefa.2005.02.001 Ã Corresponding author. Tel.: +30 210 58 31 994; fax: +30 210 53 26 446. E-mail address: giamarel@internet.gr (E.J. Giamarellos-Bourboulis).