Abstract:

Objective    To investigate temporal alterations of glutamic acid (Glu), gamma-aminobutyric acid (GABA) and glutamic acid decarboxylase isoform 67 (GAD67) in the dorso-medial nucleus of tractus solitarii (dmNTS) in rats with lymphatic brain edema (LBE) induced by cervical lymphatic blockage (CLB). Methods    Sprague-Dawley (SD) rats were randomly divided into three groups： the normal group, the sham operated group and the LBE group. Glu, GABA and GAD67 in dmNTS in rats were  detected by immuohistochemistry 1, 3, 7, 11, 15 and 21 days after CLB or sham operation. Results     Expressions of Glu and GAD67 increased 1 day after CLB, reached a peak on the 7th day, then gradually stepped down and recovered on the 21st day. Whereas reverse changes were observed in expression of GABA. No apparent difference was shown in the normal and sham operated groups. Conclusions     Alterations of Glu and GABA may participate in the dysfunction of blood pressure regulation. Early ascending expression of GAD67 promotes transformation from Glu to GABA, which contributes to neuro-functional recovery in rats with LBE.

Key words: Lymphatic brain edema; Dorsomedial nucleus of tractus solitarii; Glutamic acid; Gamma-aminobutyric acid; Glutamic acid decarboxylase isoform 67; Rats