Effects of L-Arginine on Fatty Diet Induced Changes in Adrenal Cortex: A Morphometric Study

Abstract

Aim: To study the effects of L-Arginine on high fat diet induced changes in adrenal cortex.

Study Design: A prospective experimental study.

Place and Duration of Study: This Study was conducted at the Department of Anatomy, Basic Medical Sciences Institute, Jinnah Post Graduate Medical Centre Karachi from August 2008 to October 2008.

Materials and Methods: Thirty male adult albino rats were taken for the study and were divided into three groups according to the dietary regimen. Group A received control diet. Group B received high fat diet with 20% added fat in the form of butter. Group C received high fat diet along with L-Arginine 300mg/kg / day orally. After the end of the study period that is 8 weeks, animals were weighed and sacrificed. The adrenal glands were removed, fixed in buffered neutral formalin and after processing embedded in paraffin to form blocks. 4 µm thick sections were cut and stained with H&E and Mallory’s trichrome stains for morphometeric study.     

Results: Highly significant increase in weight (P<0.001) was observed in animals of Group B and moderately significant (P<0.01) decrease was observed in Group C animals when compared to control and group B animals respectively. Cortical enlargement was found in zona glomerulosa and fasciculata and decreased thickness was observed in zona reticularis in Group B animals, when compared to control, the results were highly significant (P<0.001). In Group C decreased cortical thickness was noted in zona glomerulosa and fasciculata but in zona reticularis increase in thickness was noted when compared to Group B ,results were highly significant (P<0.001). Mallory’s trichrome stained sections of Group B animals showed dilated blood vessels in the three cortical zones, more numerous in zona fasciculata when compared to control animals. In Group C no marked change was observed in all three cortical zones when compared to control.

Conclusion: L-Arginine restricts the excessive weight gain caused by high fat diet. It also ameliorates the hypertrophic and vasodilatory effects on adrenal cortex caused by high fat diet.