engleski

Neurobiology of psychotic PTSD

Posttraumatic stress disorder (PTSD) is a psychiatric disorder that develops in some but not all persons exposed to traumatic experiences. Therefore some other factors (biological, genetic, environmental, early experiences) must be present to precipitate the development of PTSD. Combat-related PTSD is a more severe form of PTSD, sometimes associated with psychotic features. Our data, obtained in male Croatian war veterans with current and chronic combat related PTSD (SCID, DSM-IV criteria, CAPS, PANSS), with and without psychotic features, aimed to determine biomarkers associated with psychotic symptoms in PTSD. Platelet monoamine oxidase (MAO-B) activity is associated with particular personality traits and behaviours. Platelet MAO-B activity, controlled for smoking status, was significantly higher in veterans with psychotic than non-psychotic PTSD, suggesting that it might be used as a peripheral marker of the psychotic symptoms in PTSD. The MAO-B intron 13 polymorphism (a G/A substitution) was not functional, and did not affect platelet MAO-B activity. The allele frequencies of the genotypes for MAO-B, dopamine-beta-hydroxylase (DBH), catechol-O-methyl-transferase, and brain derived neurotrophic factor, were similarly distributed among psychotic or non-psychotic PTSD veterans. Plasma DBH activity did not differ between psychotic and non-psychotic PTSD veterans. DBH-1021C/T polymorphism was functional, and carriers of CC genotype had the highest DBH activity. These results suggest that DBH activity should be controlled for DBH genotypes, but DBH activity did not differentiate between psychotic and non-psychotic symptoms. Higher platelet serotonin (5-HT) concentration was associated with psychotic symptoms in different disorders. In agreement, platelet 5-HT concentration was significantly higher in veterans with psychotic than non-psychotic PTSD, and was related to positive symptoms (delusions) in PANSS subscale. These results indicate that platelet 5-HT might be used as a trait marker of psychotic symptoms in PTSD. The allele frequencies of the 5-HT transporter (5-HTT) genotype (5-HTTLPR) were significantly different between veterans with psychotic or non-psychotic PTSD, presumably due to the higher frequency of L alleles. Our data show a biological distinction (in platelet 5-HT and platelet MAO-B, and different distribution of 5-HTT genotypes) in veterans with psychotic compared to non-psychotic PTSD. References: 1. Pivac N, Kozaric-Kovacic D, Mustapic M, Deželjin D, Borovecki A, Grubisic-Ilic M, Muck-Seler D (2006) Platelet serotonin in combat related posttraumatic stress disorder with psychotic symptoms. J. Affect. Disord., 93, 223-227. 2. Pivac N, Knezevic J, Kozaric-Kovacic D, Dezeljin M, Mustapic M, Rak D, Matijevic T, Pavelic J, Muck-Seler D (2007) Monoamine oxidase (MAO) intron 13 polymorphism and platelet MAO-B activity in combat related posttraumatic stress disorder, J Affect Disord., doi: 10.1016/j.jad2007.01.017 3. Mustapic M, Pivac N, Kozaric-Kovacic D, Dezeljin M, Cubells JF, Muck-Seler D (2007) Dopamine beta-hydroxylase (DBH) activity and -1021C/T polymorphism of DBH gene in combat-related posttraumatic stress disorder. Am J Med Genetics Part B Neuropsychiatry Genetics, doi: 10.1002/ajmg.b.30526.

psychotic symptoms; combat related PTSD; Croatian veterans

Psychiatria Danubina 19 (2007) Suppl 1 (0353-5053)