Cellular correlates of kainate-induced posterior hypothalamic theta rhythm in vitro

• Autorzy: Caban B. , Staszelis A. , Kazmierska P. , Siwiec M. , Sowa J. , Kowalczyk T.
• Języki publikacji: EN

Abstrakty

EN

Hippocampal formation (HPC) theta rhythm is known to be one of the most synchronized EEG pat‑ terns in mammals. Theta field potentials in the HPC of rats are high‑amplitude, almost sinusoidal, waves in a 3‑12 Hz frequency range. It is well‑known that the posterior hypothalamic area (PHa including the supra‑ mammillary nucleus and posterior hypothalamic nuclei) is an important node in the pathway of HPC theta gen‑ eration, i.e. the ascending brainstem‑hippocampal syn‑ chronizing pathway. Furthermore, HPC theta frequency is at least partially modulated by the PHa through the activity of neurons firing in the frequency of HPC the‑ ta, at least during animals’ immobility‑related behav‑ iors. The PHa is thought to complement the activity of the medial septal area, widely known as the pacemaker of HPC theta rhythm. However, in our previous studies we discovered for the first time that cholinergic theta rhythm can also be recorded locally in deafferented pos‑ terior hypothalamic slices. Hence, in the present study we investigated PHa‑recorded theta‑related single cell activity in relation to local theta rhythm following ka‑ inic acid administration. 36 in vitro experiments were performed using brain slices (=72) taken from 36 adult Wistar rats. Each slice was perfused with 0.1 μM kain‑ ic acid to induce rhythmic activity and neuronal firing. Both field activity and corresponding cellular activity were recorded extracellularly. The relation of neuronal firing patterns to local field theta rhythm was investi‑ gated according to an existing universal classification of HPC theta‑related neurons. This study resulted in re‑ cording 17 theta‑related neurons and 77 neurons classi‑ fied as non‑related to local theta rhythm. A new neuron type (=21 cells) has been identified amongst the non‑re‑ lated group, which we termed timing cell, with a very rhythmic firing pattern in a nearly fixed frequency in the theta band. Kainate‑induced neuronal activity, re‑ corded in the posterior hypothalamic area in vitro, re‑ sembles cholinergically‑induced PHa neuronal activity, as well as well‑documented patterns of theta‑related cell discharges in the hippocampal formation in vitro and in vivo. Newly discovered PHa timing cells are discussed in light of an HPC theta rhythm frequency control mecha‑ nism. Supported by National Science Centre, Poland, No. UMO‑2017/25/B/NZ4/01476.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2018
• Tom: 78
• Numer: Suppl.1
• Opis fizyczny: p.14-15

Twórcy

autor

Caban B.

• Neurobiology Department, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland

autor

Staszelis A.

• Neurobiology Department, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland

autor

Kazmierska P.

• Neurobiology Department, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland

autor

Siwiec M.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland

autor

Sowa J.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland

autor

Kowalczyk T.

• Neurobiology Department, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland