Umezu Hanna L, Bittencourt-Silva Paloma G, Mourão Flávio A G, Moreira Fabrício A, Moraes Márcio Flávio D, Santos Victor R, da Silva Glauber S F
Department of Physiology and Biophysics, Institute of Biological Science, Federal University of Minas Gerais (ICB/UFMG), Belo Horizonte, Brazil.
Department of Physiology and Biophysics, Institute of Biological Science, Federal University of Minas Gerais (ICB/UFMG), Belo Horizonte, Brazil; Graduate Program in Neuroscience, Institute of Biological Science, Federal University of Minas Gerais (ICB/UFMG), Belo Horizonte, Brazil.
Respir Physiol Neurobiol. 2024 May;323:104229. doi: 10.1016/j.resp.2024.104229. Epub 2024 Feb 1.
This study investigated the respiratory activity in adult Wistar rats across different behavioral seizure severity induced by pentylenetetrazole (PTZ). Animals underwent surgery for electrodes implantation, allowing simultaneous EEG and diaphragm EMG (DIA) recordings and the respiratory frequency and DIA amplitude were measured. Seizures were acutely induced through PTZ injection and classified based on a pre-established score, with absence-like seizures (spike wave discharge (SWD) events on EEG) representing the lowest score. The respiratory activity was grouped into the different seizure severities. During absence-like and myoclonic jerk seizures, the breathing frequency decreased significantly (∼50% decrease) compared to pre- and post-ictal periods. Pronounced changes occurred with more severe seizures (clonic and tonic) with periods of apnea, especially during tonic seizures. Apnea duration was significantly higher in tonic compared to clonic seizures. Notably, during PTZ-induced tonic seizures the apnea events were marked by tonic DIA contraction (tonic-phase apnea). In the majority of animals (5 out of 7) this was a fatal event in which the seizure-induced respiratory arrest preceded the asystole. In conclusion, we provide an assessment of the respiratory activity in the PTZ-induced acute seizures and showed that breathing dysfunction is more pronounced in seizures with higher severity.
本研究调查了成年Wistar大鼠在由戊四氮（PTZ）诱导的不同行为性癫痫发作严重程度下的呼吸活动。动物接受电极植入手术，以便同时记录脑电图（EEG）和膈肌肌电图（DIA），并测量呼吸频率和DIA幅度。通过注射PTZ急性诱发癫痫发作，并根据预先确定的评分进行分类，失神样发作（脑电图上的棘波放电（SWD）事件）代表最低评分。将呼吸活动分为不同的癫痫发作严重程度组。在失神样发作和肌阵挛性抽搐发作期间，与发作前和发作后时期相比，呼吸频率显著降低（约降低50%）。更严重的癫痫发作（阵挛性和强直性）伴有呼吸暂停期，尤其是在强直性发作期间，会出现明显变化。强直性发作时的呼吸暂停持续时间明显长于阵挛性发作。值得注意的是，在PTZ诱导的强直性发作期间，呼吸暂停事件以强直性DIA收缩（强直期呼吸暂停）为特征。在大多数动物（7只中的5只）中，这是一个致命事件，其中癫痫发作引起的呼吸骤停先于心脏停搏。总之，我们对PTZ诱导的急性癫痫发作中的呼吸活动进行了评估，并表明呼吸功能障碍在严重程度较高的癫痫发作中更为明显。
