Premium
Serotonergic control of Purkinje cell maturation and climbing fibre elimination by 5‐HT 3 receptors in the juvenile mouse cerebellum
Author(s) -
Oostland Marlies,
Buijink M. Renate,
van Hooft Johannes A.
Publication year - 2013
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1113/jphysiol.2012.246413
Subject(s) - cerebellum , purkinje cell , biology , granule cell , receptor , climbing fiber , neuroscience , serotonin , reelin , knockout mouse , microbiology and biotechnology , medicine , endocrinology , central nervous system , biochemistry , dentate gyrus
Key points• Serotonin 3 (5‐HT 3 ) receptors are expressed by excitatory granule cells in the cerebellum during early postnatal development. • Here we show a novel role for serotonin in the regulation of cerebellar postnatal development via 5‐HT 3 receptors. • Using 5‐HT 3A receptor knockout mice we show that 5‐HT 3 receptors expressed by granule cells, via the glycoprotein reelin, regulate the morphological maturation of Purkinje cells. • The 5‐HT 3A receptor knockout mice show abnormal physiological maturation of Purkinje cells and impaired short‐term plasticity at the parallel fibre–Purkinje cell synapse, resulting in delayed climbing fibre elimination. • With these results, we provide a better understanding of the role of serotonin in the developing brain, the control it has on the postnatal maturation of the cerebellum, and the cerebellum as a highly adaptive system during early postnatal development.Abstract Functional serotonin 3 (5‐HT 3 ) receptors are transiently expressed by cerebellar granule cells during early postnatal development, where they modulate short‐term synaptic plasticity at the parallel fibre–Purkinje cell synapse. Here, we show that serotonin controls maturation of Purkinje cells in the mouse cerebellum. The 5‐HT 3 receptors regulate morphological maturation of Purkinje cells during early postnatal development, and this effect is mediated by the glycoprotein reelin. Using whole‐cell patch‐clamp recordings we also investigated physiological development of Purkinje cells in 5‐HT 3A receptor knockout mice during early postnatal development, and found abnormal physiological maturation, characterized by a more depolarized resting membrane potential, an increased input resistance and the ability to fire action potentials upon injection of a depolarizing current at an earlier age. Furthermore, short‐term synaptic plasticity was impaired at both the parallel fibre–Purkinje cell and the climbing fibre–Purkinje cell synapses, and both the amplitude and the frequency of spontaneous miniature events recorded from Purkinje cells were increased. The expedited morphological and physiological maturation affects the whole cerebellar cortical network, as indicated by delayed climbing fibre elimination in 5‐HT 3A receptor knockout mice. There was no difference between wild‐type and 5‐HT 3A receptor knockout mice in any of the morphological or physiological properties described above at later ages, indicating a specific time window during which serotonin regulates postnatal development of the cerebellum via 5‐HT 3 receptors expressed by granule cells.