P-118: The Study of Midazolam Positive Effects on Morphofunctional Activity of Rat Brain Cells in Conditions of Halothane Anesthesia
Objective: The postoperative complications (excitation, bronchitis, delayed wound healing and others) are evident after halothane anesthesia in infants with congenital palatine and upper lip cleft. General anesthetics decrease neurons activity and depress their metabolic requirement. Anesthetics are mediated through effects on neurotransmitters (GABA and glutamate), nerve signaling and may have adverse effects on the development of the central nervous system. For elimination of the postoperative complications after halothane anesthesia the usage of sedative agents with anti-hypoxic effects is advised. Besides, it is well known that the agents of benzodiazepine group modulate GABA-receptor function and ion channels inhibited by neuro-transmiters which are activated by GABA. The aim of the work is to study the brain cells functional activity and the quantity of GAD65/67 positive cells in hippocampus of sham operated rats in conditions of halothane anesthesia at Midazolam premedication. Materials and Methods: 60 adult white rats (130-150g.) were used. The intensity of RNA synthesis in system of isolated nuclei was estimated based on 14C-UTP inclusion in the non-soluble acid fraction. For this purpose material (brain tissue) was collected after 1, 24 and 168 hours after operation. The quantity of GAD65/67 cells was estimated by immunohistochemistry. Results: We have shown that halothane anesthesia induces the inhibition of transcriptional activity in rat brain cells. After an hour of operation in brain cells isolated nuclei the intensity of RNA synthesis was reduced on 40% compared with control group. The inhibition of transcriptional activity in brain cells is expressed strongly at 168 hour after the operation. It is significant that during midazolam premedication the inhibitory effect of halothane on RNA synthesis is not revealed. In particular, the transcriptional activity in the brain cells of third group animals remained like control on all periods of investigation (1, 24 and 168 hours). Conclusion: After an hour of sham operation halothane also induces proved decrease of quantity of GAD65/67 positive cells in CA3 field of hippocampus. At the same time the quantity of similar cells are increased in CA1 field. The increase of GAD65/67 positive cells in CA1 is more evident during midazolam premedication. The positive effect of midazolam detected in 1 and 24 hours after the sham operation is not revealed on a distance terms (168th hour). Based on the data received we can conclude that the positive effect of midazolam is results in increase of GAD65/67 positive cells in CA1 field of hippocampus.