Long-term high-intensity sound stimulation inhibits h current (I-h) in CA1 pyramidal neurons

Autor(es)

Siqueira Cunha, Alexandra Olimpio ^[1] ; Ceballos, Cesar Celis ^{[2, 3, 1]} ; de Deus, Junia Lara ^[1] ; Leao, Ricardo Mauricio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Physiol, FMRP, Av Bandeirantes 3900, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Yale Univ, Sch Med, Dept Cellular & Mol Physiol, New Haven, CT 06510 - USA

^[3] Univ Sao Paulo, Dept Phys, FFCLRP, Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: European Journal of Neuroscience; v. 47, n. 11, p. 1401-1413, JUN 2018.
• Citações Web of Science: 1

Resumo

Afferent neurotransmission to hippocampal pyramidal cells can lead to long-term changes to their intrinsic membrane properties and affect many ion currents. One of the most plastic neuronal currents is the hyperpolarization-activated cationic current (I-h), which changes in CA1 pyramidal cells in response to many types of physiological and pathological processes, including auditory stimulation. Recently, we demonstrated that long-term potentiation (LTP) in rat hippocampal Schaffer-CA1 synapses is depressed by high-intensity sound stimulation. Here, we investigated whether a long-term high-intensity sound stimulation could affect intrinsic membrane properties of rat CA1 pyramidal neurons. Our results showed that I-h is depressed by long-term high-intensity sound exposure (1min of 110 dB sound, applied two times per day for 10days). This resulted in a decreased resting membrane potential, increased membrane input resistance and time constant, and decreased action potential threshold. In addition, CA1 pyramidal neurons from sound-exposed animals fired more action potentials than neurons from control animals; however, this effect was not caused by a decreased I-h. On the other hand, a single episode (1min) of 110 dB sound stimulation which also inhibits hippocampal LTP did not affect I-h and firing in pyramidal neurons, suggesting that effects on I-h are long-term responses to high-intensity sound exposure. Our results show that prolonged exposure to high-intensity sound affects intrinsic membrane properties of hippocampal pyramidal neurons, mainly by decreasing the amplitude of I-h. (AU)

• Processo FAPESP: 16/01607-4 - Estimulação auditiva de alta intensidade e plasticidade sináptica
• Beneficiário: Ricardo Mauricio Xavier Leão
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 15/22327-7 - Estudo das propriedades eletrofisiológicas e morfofuncionais de neurônios do núcleo central do colículo inferior envolvidas com a gênese e propagação das crises audiogênicas
• Beneficiário: Alexandra Olimpio Siqueira Cunha
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores