Auditory evoked potential in handled and non-handled iron-deficient rats.

Luciene De Fatima Rocinholi,José Eduardo Dutra De Oliveira,João-José Lachat

doi:10.3922/j.psns.2008.2.006

Luciene De Fatima Rocinholi, José Eduardo Dutra De Oliveira + Show 1 more

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https://doi.org/10.3922/j.psns.2008.2.006

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Journal: Psychology & Neuroscience	Publication Date: Jul 1, 2008
Citations: 11	License type: cc-by

Abstract

deficiency alters metabolism, neurotransmission, glial integrity and the cortical myelin layer, besides increasing myelinization time. Environmental stimulation (handling) improves morphological, biochemical, electrophysiological and behavioral aspects of both well-nourished and malnourished animals. The objective of the present study was to determine the effects of an iron- deficient diet and of handling on the brainstem auditory evoked potential (BAEP) of rats during development. Ninety-six male rats were divided since birth into Well-nourished (W, 35 mg iron/kg) and Anemic (A, 4 mg iron/kg) groups, and subdivided into Handling (H) and No Handling (NH). Body weight, hemoglobin (Hb), hematocrit (Ht), latencies of waves I, II, III IV, I-IV interpeak interval, and response threshold to auditory stimuli were evaluated at 18, 22, and 32 days. W animals presented higher Hb and Ht levels than A animals at 18, 22 and 32 days. The animals presented longer latencies of waves I, II, III and IV and I-IV interpeak interval of BAEP at 18 than at 22 and 32 days, and AH18 rats presented longer latencies of waves I and II than AH22 and AH32 rats, and longer wave I latency than WH18 animals. Iron deficiency increased the latencies of BAEP waves, suggesting damage to the myelin layer, especially during the early development, and the effects of handling were more evident along time in anemic animals. Keywords: iron deficiency, brainstem auditory evoked potential, handling, wave latency.

Highlights

The idea of investigating the auditory evoked potentials of iron-deficient animals was based on an initial study that showed the effects of malnutrition on the brainstem auditory evoked potentials (BAEPs) of rats during development
The diet x stimulation x age interaction showed that groups Well-nourished No handling (WN) and Well-nourished Handling (WH) weighed less at 18 days than at 22 and 32 days, and less at 22 days than at 32 days
Its deficiency may cause a reduction in the amount of serum iron (Cunha, van Ravenzwaay, Mellert & Kaufmann, 2008) and in hematocrit and liver iron stores (Bourque, Iqbal, Reynolds, Adams & Nakatsu, 2008), components whose deficiency may impair tissue growth and reduce the body weight of individuals receiving iron-poor diets (Eseh & Zimmerberg, 2005)

Summary

Introduction

The idea of investigating the auditory evoked potentials of iron-deficient animals was based on an initial study that showed the effects of malnutrition (reduced amount of protein in the diet) on the brainstem auditory evoked potentials (BAEPs) of rats during development. Iron is detected throughout the rat brain, it is mainly located in the lateral and medial globus pallidus, in the substantia nigra, dentate nucleus, as well as in the putamen, nucleus ruber, thalamus, caudate nucleus (Morris, Candy, Oakley, Bloxham, & Edwardson, 1992), hippocampus (Wu et al, 2008) and, to a lesser extent, in the striatum (François, Nguyen-Legros & Percheron, 1981) This microelement is mainly located in oligodendrocytes (Connor & Benkovic, 1992), which are the cells responsible for myelination of the central nervous system, and may be present in the interstitial spaces and be associated with nerve cell processes (Hill & Switzer, 1984)

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