| First Author | Barth AM | Year | 2014 |
| Journal | Front Cell Neurosci | Volume | 8 |
| Pages | 222 | PubMed ID | 25157218 |
| Mgi Jnum | J:358746 | Mgi Id | MGI:6783524 |
| Doi | 10.3389/fncel.2014.00222 | Citation | Barth AM, et al. (2014) Ovarian cycle-linked plasticity of delta-GABAA receptor subunits in hippocampal interneurons affects gamma oscillations in vivo. Front Cell Neurosci 8:222 |
| abstractText | GABAA receptors containing delta subunits (delta-GABAARs) are GABA-gated ion channels with extra- and perisynaptic localization, strong sensitivity to neurosteroids (NS), and a high degree of plasticity. In selective brain regions they are expressed on specific principal cells and interneurons (INs), and generate a tonic conductance that controls neuronal excitability and oscillations. Plasticity of delta-GABAARs in principal cells has been described during states of altered NS synthesis including acute stress, puberty, ovarian cycle, pregnancy and the postpartum period, with direct consequences on neuronal excitability and network dynamics. The defining network events implicated in cognitive function, memory formation and encoding are gamma oscillations (30-120 Hz), a well-timed loop of excitation and inhibition between principal cells and PV-expressing INs (PV + INs). The delta-GABAARs of INs can modify gamma oscillations, and a lower expression of delta-GABAARs on INs during pregnancy alters gamma frequency recorded in vitro. The ovarian cycle is another physiological event with large fluctuations in NS levels and delta-GABAARs. Stages of the cycle are paralleled by swings in memory performance, cognitive function, and mood in both humans and rodents. Here we show delta-GABAARs changes during the mouse ovarian cycle in hippocampal cell types, with enhanced expression during diestrus in principal cells and specific INs. The plasticity of delta-GABAARs on PV-INs decreases the magnitude of gamma oscillations continuously recorded in area CA1 throughout several days in vivo during diestrus and increases it during estrus. Such recurring changes in gamma magnitude were not observed in non-cycling wild-type (WT) females, cycling females lacking delta-GABAARs only on PV-INs (PV-Gabrd (-/-)), and in male mice during a time course equivalent to the ovarian cycle. Our findings may explain the impaired memory and cognitive performance experienced by women with premenstrual syndrome (PMS) or premenstrual dysphoric disorder (PMDD). |
