Interleukin-1β increases neuronal death in the hippocampal dentate gyrus associated with status epilepticus in the developing rat

The quantitative autoradiographic [14C]-iodoantipyrine technique was applied to measure the effects of a 30-min period of pentylenetetrazol (PTZ)-induced status epilepticus (SE) on local cerebral blood flow (LCBF) in rats 10 (P10), 14 (P14), 17 (P17), and 21 (P21) days after birth. The animals received repetitive, timed injections of subconvulsive doses of PTZ until SE was reached. At P10, SE induced a 32 to 184% increase in the rates of LCBF affecting all structures studied. In P14- and P17 PTZ-treated rats, LCBF values significantly increased in two-thirds of the structures belonging to all systems studied and were not changed by SE in the parietal cortex, dorsal hippocampus, and dentate gyrus. At P21, rates of LCBF were still increased in 48 of the 73 structures studied; however, LCBF values were decreased by SE in most cortical areas, the hippocampus, and the dentate gyrus. CBF and cerebral metabolic rate for glucose (CMRglc) remained coupled in both controls and PTZ-exposed rats. Our results show that changes in LCBF with seizures are age dependent. At the most immature ages, P10 and P14, both LCBF and local CMRglc (LCMRglc) values are largely increased by long-lasting seizures. At P17 and P21, the blood flow response to SE becomes more heterogeneous, with specific decreases in the hippocampus and cortex at P21. The absence of mismatch between LCBF and LCMRglc in PTZ-exposed rats at all ages may explain at least partly why the immature brain is more resistant to seizure-induced brain damage than the adult brain.

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Malfunctional Reorganization in the Developing Limbo-Prefrontal System in Animals: Implications for Human Psychoses?

Zeitschrift für Neuropsychologie ◽

10.1024//1016-264x.12.1.8 ◽

2001 ◽

Vol 12 (1) ◽

pp. 8-14

Author(s):

Gertraud Teuchert-Noodt ◽

Ralf R. Dawirs

Keyword(s):

Prefrontal Cortex ◽

Mental Disorders ◽

Dentate Gyrus ◽

Cognitive Functions ◽

Experimental Approach ◽

Regulatory Mechanisms ◽

Hippocampal Dentate Gyrus ◽

Non Invasive ◽

Invasive Method ◽

Activity Dependent

Abstract: Neuroplasticity research in connection with mental disorders has recently bridged the gap between basic neurobiology and applied neuropsychology. A non-invasive method in the gerbil (Meriones unguiculus) - the restricted versus enriched breading and the systemically applied single methamphetamine dose - offers an experimental approach to investigate psychoses. Acts of intervening affirm an activity dependent malfunctional reorganization in the prefrontal cortex and in the hippocampal dentate gyrus and reveal the dopamine position as being critical for the disruption of interactions between the areas concerned. From the extent of plasticity effects the probability and risk of psycho-cognitive development may be derived. Advance may be expected from insights into regulatory mechanisms of neurogenesis in the hippocampal dentate gyrus which is obviously to meet the necessary requirements to promote psycho-cognitive functions/malfunctions via the limbo-prefrontal circuit.

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Voltage-activated potassium currents in acutely dissociated hippocampal dentate gyrus neurons from neonatal rats

Developmental Brain Research ◽

10.1016/0165-3806(94)90316-6 ◽

1994 ◽

Vol 81 (2) ◽

pp. 309-313 ◽

Cited By ~ 6

Author(s):

Scott C. Baraban ◽

Eric W. Lothman

Keyword(s):

Dentate Gyrus ◽

Potassium Currents ◽

Neonatal Rats ◽

Hippocampal Dentate Gyrus

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Neuronal maturation in the hippocampal dentate gyrus via chronic oral administration of Artemisa annua extract is independent of cyclooxygenase 2 signaling pathway in diet-induced obesity mouse model

IBRO Reports ◽

10.1016/j.ibror.2019.07.1005 ◽

2019 ◽

Vol 6 ◽

pp. S325

Author(s):

Pan Soo Kim ◽

Dong-Hwa Choi ◽

Sang-Kyu Park ◽

Hyeok Jin Kwon ◽

Sun Shin Yi

Keyword(s):

Mouse Model ◽

Oral Administration ◽

Dentate Gyrus ◽

Signaling Pathway ◽

Cyclooxygenase 2 ◽

Neuronal Maturation ◽

Hippocampal Dentate Gyrus ◽

Diet Induced Obesity ◽

Artemisa Annua

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Increase in extracellular dopamine levels during clozapine-induced potentiation in the hippocampal dentate gyrus of chronically prepared rabbits

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y08-036 ◽

2008 ◽

Vol 86 (5) ◽

pp. 249-256 ◽

Cited By ~ 2

Author(s):

Takashi Kubota ◽

Itsuki Jibiki ◽

Akira Ishikawa ◽

Tomomi Kawamura ◽

Sonoko Kurokawa ◽

...

Keyword(s):

Electrical Stimulation ◽

Nmda Receptor ◽

Dentate Gyrus ◽

Negative Symptoms ◽

Clinical Effect ◽

Perforant Path ◽

Hippocampal Dentate Gyrus ◽

Extracellular Dopamine ◽

Stimulation Of ◽

Synaptic Responses

We previously found that 20 mg/kg clozapine i.p. potentiated the excitatory synaptic responses elicited in the dentate gyrus by single electrical stimulation of the perforant path in chronically prepared rabbits. We called this phenomenon clozapine-induced potentiation and proved that it was an NMDA receptor-mediated event. This potentiation is presumably related to clozapine’s clinical effect on negative symptoms and cognitive dysfunctions in schizophrenia. In the present study, to investigate the mechanisms underlying clozapine-induced potentiation, we examined whether extracellular dopamine and 5-HT levels changed during the potentiation by using a microdialysis technique in the dentate gyrus. The extracellular concentrations of dopamine and 5-HT levels were measured every 5 min during all experiments. Extracellular 5-HT levels did not change, but dopamine levels eventually increased significantly during clozapine-induced potentiation. The increase in the dopamine levels occurred almost simultaneously with the induction of clozapine-induced potentiation. These results suggest that clozapine-induced potentiation is at least partly attributable to a dopamine-mediated potentiation of excitatory synaptic transmission. The present study implies that such phenomena occur also in the perforant path–dentate gyrus pathway.

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