DOPA-stained melanocytes in the macular lesions of early leprosy
Hansen. int
; 21(2): 22-8, jan.-jun. 1996. ilus
Article
in En
| LILACS
| ID: lil-194723
Responsible library:
BR1.1
RESUMO
The mechanism of association of hypopigmentation and sensorial loss in a leprosy macular lesions has not been clarified yet. The biopsy of a macular lesion on the medial face of the right forearm of a fourteen-year old male leprosy patient was submitted to DOPA-staining for melanocytes, which is specific for the melanocytic tyrosinase enzyme and it is a proper method for identifying and couting these cells in the skin. A contralateral specimen of the same patient went through the same procedure as a control experiment. The specimen from the macular lesion showed a higher number of DOPA-stained melanocytes than the control fragment. Dermal melanocytes were present in high amounts in the abnormal specimen. Increased expression of tyrosinase by melanocytes in the macular lesions may reflect a positive feed-back stimulus represented by the lack of substance tyrosine, which may in turn be utilized by the myocobacterial agent. Ultrastructural study of the normal and pathological specimens showed no significant differences in the morphological appearance of melanocytes and their melanosomes. These results suggests that the utilization of phenolic compound by the Mycobacterium leprae may be involved in the mechanism of hypopigmentation. A higher number of cases will be necessary to confirm this hypothesis.
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Index:
LILACS
Main subject:
Leprosy, Tuberculoid
/
Dihydroxyphenylalanine
/
Hypopigmentation
/
Melanocytes
Limits:
Adolescent
/
Humans
Language:
En
Journal:
Hansen. int
Journal subject:
Hansen¡ase
/
MEDICINA TROPICAL
Year:
1996
Type:
Article