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Respiratory dysfunction in two rodent models of chronic epilepsy and acute seizures and its link with the brainstem serotonin system.

ABSTRACT: Patients with drug-resistant epilepsy can experience respiratory alterations, notably during seizures. The mechanisms underlying long-term alterations in respiratory function remain unclear. As the brainstem 5-HT system is a prominent modulator of respiratory function, this study aimed at determining whether epilepsy is associated with alterations in both the respiratory function and brainstem serotonin (5-HT) system in rats. Epilepsy was triggered by pilocarpine-induced status epilepticus in rats. Our results showed that 30-50% of epileptic (EPI) rats exhibited a sharp decrease in oxygen consumption (SDOC), low metabolic rate of oxygen, and slow regular ventilation (EPI/SDOC + rats). These alterations were detected only in rats with chronic epilepsy, independent of behavioral seizures, were persistent over time, and not associated with death. In these rats, 5-HT fiber density in the nucleus tractus solitarius was lower than that in the control and EPI/SDOC- rats. Both EPI/SDOC + rats and DBA/2 mice that present with audiogenic-induced seizure followed by fatal respiratory arrest-a model of sudden and expected death in epilepsy-had increased transcript levels of tryptophan hydroxylase 2 and 5-HT presynaptic transporter. Thus, our data support that 5-HT alterations are associated with chronic and acute epilepsy-related respiratory dysfunction.

SUBMITTER: Kouchi H

PROVIDER: S-EPMC9205882 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Respiratory dysfunction in two rodent models of chronic epilepsy and acute seizures and its link with the brainstem serotonin system.

Kouchi Hayet H Ogier Michaël M Dieuset Gabriel G Morales Anne A Georges Béatrice B Rouanet Jean-Louis JL Martin Benoît B Ryvlin Philippe P Rheims Sylvain S Bezin Laurent L

Scientific reports 20220617 1

Patients with drug-resistant epilepsy can experience respiratory alterations, notably during seizures. The mechanisms underlying long-term alterations in respiratory function remain unclear. As the brainstem 5-HT system is a prominent modulator of respiratory function, this study aimed at determining whether epilepsy is associated with alterations in both the respiratory function and brainstem serotonin (5-HT) system in rats. Epilepsy was triggered by pilocarpine-induced status epilepticus in ra ...[more]

PMID: 35715469

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Dataset Information

Respiratory dysfunction in two rodent models of chronic epilepsy and acute seizures and its link with the brainstem serotonin system.

Publications

Respiratory dysfunction in two rodent models of chronic epilepsy and acute seizures and its link with the brainstem serotonin system.

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