The expression of connexin 36 and 43 in animal models of trait and state anxiety

Abstract

Few studies have investigated the role of gap junctions in anxiety. Gap junctions (GJs) are intercellular channels, and their subunit are connexins (CXs). The specific isoforms of connexins for neurons and astrocytes are CX36, and CX43 respectively. Neuronal CX36 and astrocytic CX43 are critical for brain synchrony and homeostasis. Elevated plus maze (EPM) was used for animal models of trait and state anxiety. The gene expression was assessed by Real-time PCR technique in the ventral hippocampus (v Hip), basolateral amygdala (BLA), and medial prefrontal cortex (m PC). The rats were grouped as follows (n = 6): control, trait anxiety, in which the rats were placed in the EPM apparatus, state anxiety, in which the animals were placed in the EPM apparatus after tolerating 120 min of isolation. The data showed that the anxiety of the animals in the state anxiety group was significantly greater than the trait anxiety group (p < 0.05). In the state anxiety animals, the gene expression of CX36 was lower in the m PC and BLA regions than the control and trait anxiety groups (p < 0.01). CX43 expression in the BLA, and v Hip structures was also lower than in the control and trait anxiety groups. These findings suggest that downregulation of CX36 and CX43 contributes to state anxiety pathophysiology, highlighting GJs as potential therapeutic targets.