The susceptibility of rats to pilocarpine-induced seizures is age-dependent

Cavalheiro, Ésper A.; Silva, Délrio F.; Turski, Waldemar A.; Calderazzo‐Filho, Lineu S.; Bortolotto, Zuner A.; Turski, Lechosław

doi:10.1016/0165-3806(87)90227-6

Cited by 286 publications

(164 citation statements)

References 54 publications

Supporting

Mentioning

139

Contrasting

Unclassified

Order By: Relevance

“…The potency of bicuculline in inducing seizures in the immediate postnatal period, in contradistinction to some other convulsants such as pilocarpine 3 , may be due to differential maturation of the respective neurotransmitter systems involved; the GABA system in the rat has been shown by immunocytochemistry to differentiate prenatally, earlier than other neurotransmitter systems 12,13 . Total brain concentration of GABA is 50% of adult levels at birth, while adult concentrations are found in the brainstem and cerebellum 4,8 .…”

Section: Discussionmentioning

confidence: 99%

Bicuculline induced seizures in infant rats: ontogeny of behavioral and electrocortical phenomena

Baram

Snead

1990

Developmental Brain Research

View full text Add to dashboard Cite

The effects of bicuculline, a γ-aminobutyric acid (GABA) antagonist, were investigated in 258 immature rats between the third and 22nd postnatal days. Behavioral and electrocorticographic events were correlated. Bicuculline induced both behavioral and electrographic seizures as early as the third postnatal day, an age when the CD 50 for bicuculline was lowest, and therefore the sensitivity to it was the greatest. Bicuculline may thus be a suitable convulsant for epilepsy studies involving rats during the first postnatal week.

show abstract

Section: Discussionmentioning

confidence: 99%

Bicuculline induced seizures in infant rats: ontogeny of behavioral and electrocortical phenomena

Baram

Snead

1990

Developmental Brain Research

View full text Add to dashboard Cite

show abstract

“…The observation that changes in the hippocampus tend to be region specific may explain the many conflicting reports on hippocampal alterations following excitatory intervention, particularly in the neonate. Some authors report longterm hippocampal changes following neonatal excitotoxicity [44][45][46][47][48][49], while others report that the hippocampus is relatively resistant to these changes [28,[50][51][52][53][54]. It is possible that some of these discrepancies result from methodological differences whereby only select regions of the hippocampus were examined.…”

Section: Discussionmentioning

confidence: 99%

Progressive changes in hippocampal cytoarchitecture in a neurodevelopmental rat model of epilepsy: implications for understanding presymptomatic epileptogenesis, predictive diagnosis, and targeted treatments

et al. 2017

View full text Add to dashboard Cite

Epilepsies affect about 4% of the population and are frequently characterized by a prolonged Bsilent^period before the onset of spontaneous seizures. Most current animal models of epilepsy either involve acute seizure induction or kindling protocols that induce repetitive seizures. We have developed a rat model of epilepsy that is characterized by a slowly progressing series of behavioral abnormalities prior to the onset of behavioral seizures. In the current study, we further describe an accompanying progression of cytoarchitectural changes in the hippocampal formation. Groups of male and female SD rats received serial injections of a low dose of domoic acid (0.020 mg/kg) (or vehicle) throughout the second week of life. Postmortem hippocampal tissue was obtained on postnatal days 29, 64, and 90 and processed for glial fibrillary acidic protein (GFAP), NeuN, and calbindin expression. The data revealed no significant changes on postnatal day (PND) 29 but a significant increase in hilar NeuN-positive cells in some regions on PND 64 and 90 that were identified as ectopic granule cells. Further, an increase in GFAP positive cell counts and evidence of reactive astrogliosis was found on PND 90 but not at earlier time points. We conclude that changes in cellular expression, possibly due to on-going non-convulsive seizures, develop slowly in this model and may contribute to progressive brain dysfunction that culminates in a seizure-prone phenotype.

show abstract

“…Mortality due to SE ranges from 2.5 to 20% in adults (5) and may reach moderately higher values of up to 25% in children (2)(3)(4)(5)(6)(7)(8). These data suggest that SE is a prominent factor in epilepsy, as also demonstrated experimentally in rats and mice (9)(10)(11)(12)(13)(14). In humans, late epileptic seizures may occur years after SE (4) and it should be pointed out that in children and adults who die of SE, lesions have been found in several areas of the brain (2,4,8).…”

Section: Introductionmentioning

confidence: 89%

“…In both cases, however, the rats eventually progress to SE (18)(19)(20). The long-term consequences of SE, such as those observed in adult rats and mice (10,11), are spontaneous seizures secondarily generalized and accompanied by structural damage to the brain. Chronic epilepsy thus provoked is similar in many aspects to human temporal lobe epilepsy and as such is a good model for this human disease.…”

Section: Introductionmentioning

confidence: 99%

Absence-like seizures in adult rats following pilocarpine-induced status epilepticus early in life

Ferreira

Valle

Cavalheiro

et al. 2003

Braz J Med Biol Res

View full text Add to dashboard Cite

Administration of pilocarpine causes epilepsy in rats if status epilepticus (SE) is induced at an early age. To determine in detail the electrophysiological patterns of the epileptogenic activity in these animals, 46 Wistar rats, 7-17 days old, were subjected to SE induced by pilocarpine and electro-oscillograms from the cortex, hippocampus, amygdala, thalamus and hypothalamus, as well as head, rostrum and vibrissa, eye, ear and forelimb movements, were recorded 120 days later. Six control animals of the same age range did not show any signs of epilepsy. In all the rats subjected to SE, iterative spike-wave complexes (8.1 ± 0.5 Hz in frequency, 18.9 ± 9.1 s in duration) were recorded from the frontal cortex during absence fits. However, similar spike-wave discharges were always found also in the hippocampus and, less frequently, in the amygdala and in thalamic nuclei. Repetitive or single spikes were also detected in these same central structures. Clonic movements and single jerks were recorded from all the rats, either concomitantly with or independently of the spike-wave complexes and spikes. We conclude that rats made epileptic with pilocarpine develop absence seizures also occurring during paradoxical sleep, showing the characteristic spike-wave bursts in neocortical areas and also in the hippocampus. This is in contrast to the wellaccepted statement that one of the main characteristics of absence-like fits in the rat is that spike-wave discharges are never recorded from the hippocampal fields. Correspondence

show abstract

The susceptibility of rats to pilocarpine-induced seizures is age-dependent

Cited by 286 publications

References 54 publications

Bicuculline induced seizures in infant rats: ontogeny of behavioral and electrocortical phenomena

Bicuculline induced seizures in infant rats: ontogeny of behavioral and electrocortical phenomena

Progressive changes in hippocampal cytoarchitecture in a neurodevelopmental rat model of epilepsy: implications for understanding presymptomatic epileptogenesis, predictive diagnosis, and targeted treatments

Absence-like seizures in adult rats following pilocarpine-induced status epilepticus early in life

Contact Info

Product

Resources

About