Neonatal Antidepressant Exposure has Lasting Effects
Neonatal Antidepressant Exposure has Lasting Effects on Behavior and Serotonin Circuitry [Neuropsychopharmacology]
Since we’ve had some articles on SSRIs before, I thought I’d add this one.
Here’s the central result:
In neonatal rodents, chronic administration of serotonin reuptake inhibitors (clomipramine, fluoxetine, zimeldine, LU-10-134C) as well as some other tricyclic antidepressants but not the atypical antidepressants iprindole or nomifensine during the early life period from postnatal day 8 (PN8) to PN21 results in a pattern of maladaptive behaviors that are evident long after drug discontinuation and persist into adulthood (Mirmiran et al, 1981; Hilakivi et al, 1984; Hilakivi and Hilakivi, 1987; Hansen et al, 1997; Ansorge et al, 2004). These behavioral changes, described here as the ‘neonatal antidepressant exposure syndrome (NADES)’, in rats include alterations in locomotor activity, reduced male sexual activity and competence, increased ethanol consumption, dysregulation of the hypothalamic-pituitary-adrenal axis, increased rapid eye movement (REM) sleep time and reduced latency to enter the REM sleep phase, and increased immobility in the forced swim test (Mirmiran et al, 1981; Hilakivi et al, 1984; Hilakivi and Hilakivi, 1987; Hartley et al, 1990; Hansen et al, 1997). In contrast, adults exposed to similar doses and durations of antidepressants exhibit no persistent behavioral effects after drug discontinuation, indicating that the neurobiological response to long-term antidepressant administration differs markedly between early life and adulthood.
These findings indicate that there is some early (in development) regulation of the 5HT system. Without “proper” development, the organism suffers long-lasting deficits, but if the 5HT system is exposed to modulatory SSRIs later in life, there are no long-term changes. Interesting. I wonder what developmental switches (genes, etc.) are responsible for this difference.