Author's Name:	Billakanti Prakash Babu, Ramachandra Bhat K & Muddanna S Rao
Subject Area:	Health Science
Subject	Other
Section	Research Paper

Restraint Stress, Neurodegeneration, Substantia nigra, Albino Mice, Dendritic morphology.

Brain is highly dynamic organ and plastic structure. It can be affected by stress, toxins and malnutrition. This study was conducted to see the effect of restraint stress during preweaning period on the development of neurons of substantia nigra.In the present experiment on new born pups of albino mice of BALB/C strain were restrained for 6 hours daily from birth till postnatal day 21 (21 days stress) and from postnatal day 16 to 21 day (5 day stress) in a restraining device, which consists of a wooden platform to which a wire-mesh was attached. At the postnatal day 22 (P22) these pups were sacrificed. Substantia nigra was dissected out and processed for Golgi staining.Well stained nigral neurons were quantified by concentric circle method, data was analyzed by unpaired ‘t’ test.both in control and experimental groups. In mice subjected to 21 days restraint stress throughout preweaning age resulted in significant decrease in dendritic intersections in all the concentric circles, dendritic branching points at 1st (0-20µ ), 2nd (20-40µ), 3rd (40-60µ) and 4th (60-80µ) concentric zones. It also induced gastric ulcers and there was increase in wet weight of suprarenal gland. However, 5 days of stress during postnatal day 16th to 21st (P16-P21) did not affect any of the parameters, except increase in suprarenal weight.Stress from day of birth has more effect on the development of nigral neurons than during later part. Altered dendritic arborization may affect the afferent projections on these neurons and subsequently on the normal functioning of the neurons.