The 5HT receptor transcripts are localized to identified CNS neurons whose neuritogenesis is induced or inhibited by serotonin.

R5HT transcripts are found in identified CNS neurons

Abstract

Introduction. Several neurological conditions have their foundation in the failure of neuritic regeneration in neurons in the central nervous system. The solution of this failure can involve multiple factors. The monoamine neurotransmitter serotonin can regulate the mobility and behavior of animals and at the cellular level, it can also regulate neurogrowth. Previously we reported that serotonin induces or inhibits neuritic regeneration of CNS neurons in culture, depending on the neuronal type on which it acts. In Rz neurons, it induces inhibition of neuritogenesis, whereas in AL1 neurons, it induces neurite outgrowth. A wide variety of serotonin receptors has been reported, and many of them have subtypes, all with different functions, both excitatory and inhibitory of neuronal activity.

Hypothesis: It is possible that the neuritogenic capacity of these neurons in culture is related to the expression of different types of receptors on their cell membrane. Methods. To test this hypothesis, we isolated central nervous system (CNS) ganglia from the Mexican leech Haementeria officinalis. We synthesized probes for the serotonin 5ht1a and 5ht2 receptors based on the leech transcriptome. We isolated identified Rz and AL1 CNS neurons and exposed them to hybridization medium and conditions with the digoxigenin- and X-purple. Results: In this work, we report the presence of the 5HT2 receptor in AL1 neurons, suggesting that the extensive growth induced by serotonin is associated with the activation of the serotonin type 2 receptor. Furthermore, Rz neurons were recognized by the probe synthesized to recognize the 5ht1A receptor, suggesting that the inhibition of neuritogenesis is associated with the activation of this receptor.
Conclusion. This data suggests that neuritogenesis in the neurons studied may be regulated by the expression of serotonin receptors 5HT1a or 5HT2.