Laboratorio de Neurobiología de la Memoria, IFIByNE-CONICET, Departamento de Fisiología Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pab. II, (C1428EHA), Buenos Aires, Argentina.
Physiol Behav. 2013 Feb 17;110-111:198-205. doi: 10.1016/j.physbeh.2012.12.013. Epub 2012 Dec 30.
Conspicuous and sustained heart arrests, revealed as an increase in the magnitude of cardiac interbeat intervals, are elicited in the crab Neohelice granulata upon the presentation of a visual danger stimulus (VDS). Aiming to study the regulation of cardio-inhibitory responses (CIR) in vivo, we investigated whether GABA mediates the extrinsic regulation of the cardiac activity. We examined the possibility of abolishing CIR by injecting the GABAergic antagonists picrotoxin and bicuculline, right before sensory stimulation. Picrotoxin partially abolished the reversible cardiac arrests induced by VDS, whereas bicuculline showed no effects. These results suggest that the rapid responses of the cardiac system of the crab Neohelice to environmental disturbances, reminiscent of an autonomic-like regulation associated with fear, flight or fight, may be extrinsically regulated by the GABAergic system.
在视觉危险刺激（VDS）呈现时，会在蟹 Neohelice granulata 中引起明显且持续的心脏骤停，表现为心动间期幅度增加。为了研究体内心脏抑制反应（CIR）的调节，我们研究了 GABA 是否介导心脏活动的外在调节。我们通过在感觉刺激前注射 GABA 能拮抗剂（如印防己毒素和荷包牡丹碱）来检验是否可以消除 CIR。印防己毒素部分消除了 VDS 诱导的可逆性心脏骤停，而荷包牡丹碱则没有影响。这些结果表明，蟹 Neohelice 的心脏系统对环境干扰的快速反应可能受到 GABA 能系统的外在调节，这种反应类似于与恐惧、逃避或战斗相关的自主样调节。
