Pérez ECA, Aguirre TMC, Hernández AME, García HLI, Manzo DJ, Carrillo CP

Language: Spanish
References: 24
Page: 12-21
PDF size: 890.83 Kb.

ABSTRACT

Introduction: We have previously used horseradish peroxidase (WGA-HRP) for determining functional aspects related to the intracellular transport of substances in motoneurons of the Pubococcygeus (Pc) muscle, which participates in seminal emission and micturition processes in male rats. We have described the effect of steroids and oxytocin (OT) manipulation on motoneurons staining, specifically, reduction of such hormones produce a decrease in the pattern of Pc motoneurons morphology whereas of hormones increase staining. Despite the fact that we have observed the area of dendritic arborization of these motoneurons is dependent on hormones, we however have not analyzed yet whether there is a “differential morphological sensitive” in their dendritic projections within the grey matter of spinal cord dependent on OT. Objectives: To test this hypothesis, we analyzed the dendrites of motoneurons in three regions: ventral, dorsolateral, and central canal of the sixth lumbar and the first sacral segments of the spinal cord of rats. Materials and methods: Wistar Male Rats were grouped in: intacts; spinal injury treated with saline solution; and spinal injury treated with OT. The motoneurons were stained with WGA-HRP and their dendrites were analyzed. Results: Spinal cord injury diminished the length of primary dendrites in motoneurons projected to the three spinal regions. The OT restores the damage produced by spinal cord injury. Dendrites projecting to the dorsolateral area were significantly larger. Conclusions: The OT mainly promotes the activity in the intracellular transport of substances insidedendrites of Pc motoneurons projecting to autonomic region in the spinal cord of male rat.

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