FEATURES OF THE POST-SEIZURE DEPRESSION PERIOD IN KINDLED RATS UNDER TRANSCRANIAL APPLICATION OF LOW-INTENSITY PULSED ULTRASOUND

Abstract

Epilepsy is accompanied not only by convulsive seizures but also by pronounced comorbid behavioral and neurological disorders, particularly post-seizure depression. Investigating these comorbid reflex and motor impairments in rats with chronic epileptic syndrome represents a significant scientific and practical challenge. Post-seizure depression acts as a mechanism for seizure termination, fundamentally driven by the activation of the brain's endogenous antiepileptic networks, including the opiatergic system. The application of non-invasive neuromodulation techniques, such as low-intensity pulsed ultrasound (LIPUS), provides a promising approach for exploring the mechanisms of corrective influence on the functional activity of the brain and mitigating these comorbid disorders. Aim. To investigate the effects of single and repeated (five sessions) transcranial non-invasive LIPUS application on the manifestations of post-seizure depressive syndrome, including reflex, coordination, and postural impairments, in rats with pharmacological kindling. Material and methods. The experiment was conducted on 42 adult male Wistar rats. Chronic epileptic syndrome was induced by daily intraperitoneal injections of pentylenetetrazol (PTZ) at a dose of 35.0 mg/kg for 21 days. The animals were divided into intact control groups and kindled groups receiving either sham stimulation or transcranial LIPUS application (1 or 5 sessions). LIPUS parameters included a frequency of 1.5 MHz, an intensity of 30 mW/cm2, and a 20-minute session targeting the parieto-occipital zone. Post-seizure motor coordination, muscle tone, and pain sensitivity were assessed. Results. PTZ-kindled rats exhibited severe coordination and muscle tone impairments: a 55.7-61.9 % reduction in the hanging time on the horizontal wire compared to intact controls (P<0.001), elevated tail muscle tone (in 85.7 % of animals), exophthalmos, and adducted limb posture. Transcranial LIPUS application effectively corrected these deficits. A five-session LIPUS course significantly increased the horizontal wire hanging time by 50.6 % compared to the kindled sham group (P<0.02). Furthermore, the repeated ultrasound treatment restored normal abducted limb posture, eliminated exophthalmos, and reduced pathological tail muscle hypertonia. However, LIPUS did not alter the diminished pain sensitivity in response to mechanical stimulation, indicating the specificity of its neuromodulatory effects. Conclusions. Non-invasive transcranial LIPUS application, particularly when administered as a five-session course, is a promising therapeutic strategy for alleviating comorbid motor, postural, and coordination disorders during the post-seizure period in chronic epileptic syndrome.

Abstract via crossref.

Flags from extraction

• exposures[0].unspecified_domain.isppa_w_cm2 — Intensity 30 mW/cm2 given without metric (Isppa/Ispta) or domain; placed in isppa slot as a guess of metric
• exposures[0].timing.pulse_duration_ms — Only 'duration of pulse series 200 us' stated; unclear whether pulse or burst train; no PRF or duty cycle
• n_sessions_per_subject — Sessions stated in words (one or five sessions) by group
• exposures[0].target.terms — Parieto-occipital zone of skull, cortex target only approximate