In rats that suffered severe blood loss, the drug semax helped keep spleen serotonin levels from dropping a week after the injury. The study also showed changes in stress hormones and oxidative stress after the shock, but these findings are specific to an acute trauma model and not directly useful for everyday health or performance goals.

LPO products were measured in plasma and biogenic amines (serotonin, adrenalin, noradrenalin) in tissues of rats in different periods after hemorrhagic shock provoked by taking blood and maintenance of arterial pressure at the level of 40 mm Hg for 1 hour. Resuscitation was conducted by administration of autoblood. It was found that splenic serotonin levels decreased on experiment day 7 and went up on day 28. On late experiment stages noradrenalin levels in the adrenals were high. Early after resuscitation the trend was noted to higher LPO products concentration in plasma and serotonin in the brain stem. Intravenous injection of semax prevented serotonin fall in the spleen on experiment day 7. It is suggested that biogenic amines, especially serotonin system, are involved in mechanisms of postresuscitation disorders, in cerebral defects in particular, through prolongation of secondary hypoxia early after hemorrhagic shock and activation of hypothalamo-hypophyso-adrenal system late after the shock.