SciELO - Scientific Electronic Library Online

 
vol.32 issue1Differential in vitro pathogenicity of predatory fungi of the genus Monacrosporium for phytonematodes, free-living nematodes and parasitic nematodes of cattlePostnatal development of rats exposed to fluoxetine or venlafaxine during the third week of pregnancy author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Brazilian Journal of Medical and Biological Research

On-line version ISSN 1414-431X

Abstract

CLARKE, J.A.; DALY, M. de B.; EAD, H.W.  and  HENNESSY, E.M.. The carotid body of the spontaneous insulin-dependent diabetic rat. Braz J Med Biol Res [online]. 1999, vol.32, n.1, pp. 85-91. ISSN 1414-431X.  http://dx.doi.org/10.1590/S0100-879X1999000100013.

The carotid bodies from adult spontaneous insulin-dependent diabetic rats (strain BB/S) were perfusion-fixed at normal arterial blood pressure with 3% phosphate-buffered glutaraldehyde and compared with the organs from control rats (strain BB/Sc) prepared in the same way. Serial 5-µm sections were cut, stained, and using an interactive image analysis system, were analysed to determine the volumes of the carotid body and its vascular and extravascular compartments. There was no evidence of systemic arterial disease in the carotid stem arteries in either group of animals, and the microvasculature of the organs appeared normal by light microscopy. The volume of the carotid body was unchanged 3 months after the onset of diabetes but was increased at 6 months. The total vascular volume of the organ was unchanged, but the volume of the small vessels (5-12 µm) was increased. In the control group the small vessels comprised 5% of the total volume of the carotid body, or about 44% of the vascular compartment. The percentage of small vessels increased at 3 months in the diabetic group, but had returned to normal at 6 months. The extravascular volume followed the same pattern as the total carotid body volume and so did not change appreciably when expressed as a percentage of the total volume of the organ. The increase in size of the carotid body in diabetic rats is due, therefore, to an augmented extravascular volume. In one diabetic specimen the carotid sinus nerve showed signs of diabetic neuropathy, axonal swelling and intramyelinic oedema. The clinical implications of these results are discussed.

Keywords : diabetic rat; carotid body; quantitative morphology; vascular compartment.

        · text in English     · pdf in English