Effects of combined pre- and post-natal protein deprivation on the myenteric plexus of the esophagus of weanling rats: A histochemical, quantitative and ultrastructural study

Abstract

AIM:To evaluate the effects of protein deprivation on the myenteric plexus of the esophagus of weanling rats. METHODS:Pregnant female Wistar rats were divided into 2 groups: nourished (N), receiving normal diet, and undernourished (D), receiving a protein-deprived diet, which continued after birth. At twenty-one days of age, 13 esophagi from each group were submitted to light microscopy and morphometrical analysis employing the NADH diaphorase, NADPH diaphorase and acetylcholinesterase techniques. Three other esophagi from each group were evaluated with transmission electron microscopy (TEM). RESULTS:In both the NADH-and the NADPH-reactive mounts, the neurons of the N mounts were more intensely stained, while in the D esophagi only the larger neurons were reactive. Many myenteric neurons of N were intensely reactive for AChE activity but only a few neurons of D exhibited these aspects. Ultrastructural analysis revealed that the granular reticulum of N showed large numbers of ribosomes aligned on the outer surface of its regularly arranged membrane while the ribosomes of D were disposed in clusters. The chromatin was more homogeneously scattered inside the neuron nucleus of N as well as the granular component of the nucleolus was evidently more developed in this group. Statistically significant differences between N and D groups were detected in the total estimated number of neurons stained by the NADPH technique. CONCLUSION:The morphological and quantitative data shows that feeding with protein-deprived diet in 21-d old rats induces a delay in the development of the myenteric neurons of the esophagus.

Metabolic effects of early protein undernourishment and renourishment in wistar rats

“…Several authors have worked with similar experimental protocols to the one used in the present study; however, they used 42 day-old animals (CASTELUCCI et al, 2002;GOMES et al, 2006;GREGGIO et al, 2010;LIBERTI et al, 2007;OLIVEIRA et al, 2010). Since there are no indications in these studies of animals being monitored in the period evaluated (60 days), nor of any metabolic monitoring.…”

“…The experimental protocol was performed with adaptations from previously published work by our group (GREGGIO et al, 2010;LIBERTI et al, 2007;OLIVEIRA et al, 2010). Wistar rats (Rattus norvegicus) were used (23 males and 23 females, between 90 and 120 d of age with body masses between 280 and 320 g), obtained from the animal colony of the Biomedical Science Institute, USP.…”

“…Several studies have been published on the effects of protein undernourishment and the role the renourishment plays in various organs and tissues (BAPTISTA JS et al, 2013;GREGGIO et al, 2010;LIBERTI et al, 2007;OLIVEIRA et al, 2010). However, the morphological and structural changes caused by this state of protein deprivation did not reveal or bring understanding to the metabolic aspects of the adopted experimental model.…”

Aspectos histoquímicos e quantitativos da renutrição precoce e tardia no córtex cerebral de ratos Wistar

“…Segundo Santer e Conboy (1988), o número de neurônios do plexo mioentérico diminuiu cerca de 27% no intestino delgado de ratos. Uma diminuição significativa desses neurônios (aproximadamente, 33%) também foi determinada por Gomes et al (2006) no intestino delgado de ratos e, por Liberti et al (2007), no esôfago de ratos (aproximadamente, 30%); particularmente para essa órgão, os autores determinaram uma diminuição de cerca de 50% no número de neurônio nitrérgicos, quando comparado ao grupo controle. Habacuque (2010) observou que a subnutrição protéica alterou o desenvolvimento dos animais e dos componentes do plexo traqueal de ratos Wistar.…”

<b>Avaliação morfoquantitativa e ultraestrutural da cartilagem do processo condilar da mandíbula e da sincondrose basioccipital de ratos Wistar subnutridos e suplementados com resveratrol</b>

“…Todavia, é quando se analisa a ultraestrutura celular, que se consegue estabelecer algumas diferenças importantes. Trabalhos que envolvem esse tipo de avaliação têm sido realizados, por exemplo, em neurônios da hipófise macacos e do plexo mioentérico de ratos subnutridos (CÓNSOLE et al, 2001;LIBERTI et al, 2007), e em condrócitos da cartilagem articular de camundongos submetida a processos degenerativos como a osteoartrite e o envelhecimento (YAMAMOTO et al, 2005). Além disso, a subnutrição interferiu na deposição das fibras colágenas do tipo II constituintes da SBo, elevando a densidade de fibrilas no período pré-púbere (grupo S).…”