Morphological Changes in the Hippocampus of the Rat Brain in Ischemia and in Conditions of Combined Preconditioning

BACKGROUND:Preconditioning is effective for increasing the body’s resistance to hypoxia/ischemia. AIM: To evaluate morphological changes in the most hypoxia-sensitive fields of the hippocampus CA1 and CA3 in cerebral ischemia in rats and under conditions of combined preconditioning.MATERIALS AND METHODS:Cerebral ischemia was simulated in rats under anesthesia (8% chloral hydrate solution, 400 mg/kg) by bilateral ligation of the common carotid arteries. The combined preconditioning method included the alternate use of two preconditional factors: pharmacological (amtisol, 25 mg/kg) and hypoxic (hypobaric hypoxia, 410 mmHg; exposure time, 60 min). Morphometric assessment of brain damage was performed a day after modeling ischemia in the CA1 and CA3 fields of the hippocampus. RESULTS: Combined preconditioning has a positive effect on the morphometric parameters of the brain during ischemia, including increasing neuronal survival in the early and late periods of ischemia modeling, preventing the formation of necrotically and apoptotically altered neurons, hyperactivation of microglial cells, and contributing to endotheliocyte preservation.CONCLUSIONS:Combined preconditioning (amtisol + hypobaric hypoxia) has a neuroprotective effect in cerebral ischemia.