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Y Tanii

Publications and source records attributed to Y Tanii.

28 records · Page 2Linked to original sources
PubMed1987

Serial changes of the susceptibility of epileptogenic focus during hippocampal kindling induced with low-frequency electrical stimulation in cats.

Cats were stimulated in the dorsal hippocampus with low-frequency square wave pulses. All subjects were kindled until generalized convulsion occurred. In the early stage of the kindling process, an increase in the interpulse interval and a decrease in the number of stimulating pulses required for the provocation of epileptic afterdischarge were observed, but in the late stage a decrease in the former and an increase in the latter were observed. It appears from these data that completion of hippocampal kindling is accompanied by a decrease in excitability at the site of stimulation subsequent to an increase in the same.

Animals↗
PubMed1987

Acute effect of some psychotropic drugs on low-frequency amygdaloid kindled seizures.

We assessed the acute effects of some psychotropic drugs on amygdaloid-kindled seizures produced by low-frequency stimulation. We used the number of stimulating pulses required for the induction of epileptic afterdischarge (pulse-number threshold, PNT) as an indicator for the seizure-generating threshold, and the duration of the epileptic afterdischarge (AD duration, ADD) as an indicator for the duration of the induced seizures. Methamphetamine and atropine elevated the PNT and reduced the ADD. Haloperidol reduced the PNT at all tested doses and reduced the ADD at high dosage. Imipramine elevated the PNT at low doses and reduced the PNT at high dosage. Imipramine also reduced the ADD. Reserpine at high dose elevated the PNT without affecting the ADD.

Amygdala↗
PubMed1987

Acute effect of TRH, flunarizine, lithium and zotepine on amygdaloid kindled seizures induced with low-frequency stimulation.

We assessed the acute effects of various drugs on amygdaloid kindled seizures induced with low-frequency stimulations. We used the number of stimulating pulses required for the induction of epileptic afterdischarge (pulse-number threshold; PNT) as an indicator of the seizure generating threshold and the duration of induced seizures (AD duration; ADD) as an indicator of the seizures. TRH increased the PNT without affecting the ADD at a high dose (1.2 mg/kg). Flunarizine decreased the PNT and ADD simultaneously at a high dose (50 mg/kg). Lithium increased the PNT without affecting the ADD at two doses (100 mg/kg, 200 mg/kg). Zotepine decreased the PNT without affecting the ADD at two doses (8 mg/kg, 16 mg/kg). We propose that the technique of low-frequency kindling is a useful experimental model in assessing the effects of antipsychotic or antiepileptic drugs on the excitability of the limbic regions.

Amygdala↗
PubMed1987

["Saving-effect" of stimulating pulses at low-frequency limbic kindling in cats].

To assess the development of kindling effect induced with low frequency electrical stimulations, we stimulated the lateral amygdala (AM group, 5 cats) and the dorsal hippocampus (HP group, 5 cats) bipolarly, once a day, with 2 mA base to peak, biphasic 1 msec square-wave pulses. In each stimulation we measured the longest inter-pulse interval required for the provocation of epileptic afterdischarge (AD), defined as the pulse-interval threshold; and the number of stimulating pulses required for the provocation of AD at this pulse-interval, defined as the pulse-number threshold. The observed behavioral seizures were classified into 6 stages in both the AM and HP group according to the conventional classification. In the AM group, an increase of the pulse-interval threshold and a decrease of the pulse-number threshold were observed during the kindling process. At the completion of kindling, a generalized convulsion was provoked with 1,200-1,600 msec pulse-intervals, and with 8-12 stimulating pulses. In the HP group an increase of the pulse-interval threshold and a decrease of the pulse-number threshold were observed in the early seizure stages, but not so significantly as the AM group. In the late seizure stages, a decrease of the pulse-interval threshold and an increase of the pulse-number threshold were observed. The observed behavioral stage of seizures in the two groups were similar to that of the conventional high-frequency kindling.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Saving-effect of stimulating pulses at low-frequency amygdaloid kindling in cats.

Cats were stimulated in the lateral amygdala with low-frequency square-wave pulses. All subjects were kindled until generalized convulsion occurred. During the kindling process, a prolongation of the interpulse interval and a reduction of the number of pulses required for the provocation of afterdischarges were observed. We refer to this phenomenon as the 'saving-effect' of stimulating pulses to provoke afterdischarges.

Action Potentials↗
PubMed1986

Low-frequency kindling as a new experimental model of epilepsy.

Ten cats were stimulated twice a day in the lateral amygdala with low-frequency stimulation of about 3 Hz until generalized convulsion occurred. After the completion of kindling, the longest interpulse interval required for provocation of generalized convulsion (pulse-interval threshold) was determined in each subject. The pulse-interval threshold was 1300 ms in five cats, and 900 ms in five other cats. Then the stability of pulse-interval threshold and of the number of stimulating pulses required for provocation of afterdischarge when the stimulation was delivered with the pulse-interval threshold (pulse-number threshold) was tested. The pulse-interval threshold, pulse-number threshold, and duration of afterdischarge in each stimulation did not change statistically at the interstimulation interval from 24 h to 7 days. Phenobarbital and diphenylhydantoin elevated the pulse-number threshold significantly. We propose that low-frequency kindling is a valuable experimental model of epilepsy in assessing simply and precisely the susceptibility of the epileptic focus itself and the severity of epileptic seizures.

Animals↗
PubMedDate not supplied

Plasma thrombomodulin values and hepatorenal function in the elderly.

To define the clinical significance of plasma thrombomodulin (TM) values in elderly, we examined plasma TM in healthy young subjects, healthy elderly subjects and patients with cerebral infarction sequelae. We also studied the relationship with effective renal plasma flow (ERPF) and with the liver's protein-production ability. The TM values of healthy elderly subjects were higher than those of healthy young subjects. There existed an inverse correlation between TM values and ERPF. Accordingly, high TM values might significantly influence renal arteriosclerosis. From the inverse correlation identified between TM and serum cholinesterase, it was estimated that high TM might appear in conjunction with the liver's protein production ability. Patients with cerebral infarction showed higher plasma TM values. It is thought that angiopathy has been maintained in patients as the anamnesis of cerebral infarction even though it occurred in the past. The TM values of patients with diabetes mellitus (DM) were higher than those without it. Moreover, the TM values of patients with DM complicated by retinopathy were higher than those uncomplicated by retinopathy. It is therefore estimated that increased TM might occur with angiopathy resulting from DM. A possibility thus exists that plasma TM could be utilized as one of the markers for endothelial injury.

Journal Article↗
PubMedDate not supplied

Acute effect of anticonvulsants on amygdaloid kindled seizures induced with low-frequency stimulations.

Acute effects of several antiepileptic drugs on low-frequency amygdaloid-kindled seizures were assessed. The number of stimulating pulses required for the provocation of epileptic afterdischarge (pulse-number threshold, PNT) was used as an indicator for the seizure-generating threshold. The duration of epileptic afterdischarge (AD duration) was used as an indicator for the severity of the induced seizures. Phenytoin (PHT) and carbamazepine (CBZ) reduced AD duration more than did elevating PNT. Conversely, phenobarbital (PB) and diazepam (DZP) elevated PNT more than did reducing AD duration. Weak effects on the two indicators, valproic acid (VPA) and ethosuximide (ESM), were observed. Low-frequency kindling may be a useful experimental model of epilepsy in drug-assessments.

Amygdala↗