Comparison of physical development and rate of formation sensory-motor reflexes offspring of rats with different experimental model of preeclampsia

Abstract

Summary. A comparative study of the physical development and the rate of formation of sensory-motor reflexes offspring of rats with experimental preeclampsia (EP) was carried out. In the first experimental group EP was modeled intraperitoneal conduct of L-NAME at a dose of 25 mg/kg from 14 to 21 days of gestation, the second experimental group — the replacement of drinking water by 1.8% sodium chloride solution for the entire period of gestation. In the offspring of both groups, there was a delay of physical development, which was reflected in the later timing of the hair coat development, incisor eruption, pinna detachment as compared to the pups in the control group. It also noted the gap in the formation of sensory-motor reflexes and vestibular reactions. This was manifested in the delayed appearance of the olfactory response, auditory sensitivity, later performing tests «righting reflex», «negative geotaxis», «aerial righting reflex», «cliff avoidance», «horizontal wire test», «raising the head and forelegs», «supporting their bodies on hind legs» as compared to the indices of the pups of the female rats with an uncomplicated pregnancy. The most pronounced lag in postnatal development was observed in the offspring of rats with EP, which instead of drinking water was prepared 1.8% sodium chloride during the entire period of gestation. The purpose. To make a comparative study of the impact of ADMA-like preeclampsia (PE) and preeclampsia modeled by the replacement of drinking water consumed by female rats during gestation with 1.8% NaCl solution on the physical development and the rate of the maturation of sensory motor reflexes of their offspring. Methods. The study was performed on three groups of pregnant female rats aged 3—4 months whose original weight was 210—250 g and their pups. They were divided into three groups: 1: Control group including female rats with an uncomplicated pregnancy (n = 6) and their pups (n = 49); 2. Experimental group 1 — pregnant female rats with PE (n = 6) induced by intraabdominal introduction of L-NAME at a dose of 25 mg/kg from 14 to 21 day of gestation (ADMA-like preeclampsia) and their offspring (n = 35); 3. Experimental group 2 — pregnant female rats with PE (n = 6) modeled by the replacement of drinking throughout gestation with 1.8% NaCl solution and their pups. When studying the physical development of the pups we considered the terms of pinna detachment, hair coat development, incisor eruption and the time when they began to open their eyes. To estimate the rate of the maturation of sensory motor reflexes and motor coordination of the pups of the rats with PE we analyzed the time when they started to support their bodies on hind legs, lift their bodies off the floor, crawl, raise their head and forelegs, show the aerial righting reflex and the righting reflex, negative geotaxis, reactions to auditory and olfactory stimuli as well as the time they managed to stay on the horizontal wire. Results. The pups of the female rats with PE of both experimental groups were found to have later pinna detachment, incisor eruption and hair coat development as compared to the indices of the control group. In addition, the offspring of the experimental groups demonstrated a delay in the performance of the following tests: «righting reflex», «negative geotaxis», «aerial righting reflex», «cliff avoidance», «horizontal wire test», «raising the head and forelegs», «supporting their bodies on hind legs», «reaction to an olfactory stimulus» and «reaction to an auditory stimulus» as compared to the indices of the pups of the female rats with an uncomplicated pregnancy. Conclusion. PE induced by the introduction of ADMA to pregnant female rats and by the replacement of drinking water consumed by female rats during gestation with 1.8% NaCl solution causes a delay in physical development, maturation of sensory motor reflexes and vestibular reactions in their offspring.