Ms. Omar et al., HISTOCHEMICAL DISTRIBUTION OF ESTERASES IN ADULT ONCHOCERCA-FASCIATA (FILARIOIDEA, ONCHOCERCIDAE), Tropical medicine and parasitology, 44(4), 1993, pp. 295-298
The localization and distribution patterns of non-specific esterases (
NSE) and acetylcholinesterase (AChE) activities in adult female Onchoc
erca fasciata (Filarioidea: Onchocercidae) have been determined using
enzyme histochemical techniques. NSE activity was highest in the hypod
ermis and mild to moderate in the somatic musculature and uterine epit
helium. The intensity of the reaction was decreased but not eliminated
by sodium fluoride. AChE activity was found in the hypodermis and cut
icle of the female worm, highest in fully formed microfilariae in the
uterus, whereas early oocytes and embryonic forms were negative. Butyr
ylcholinesterase activity showed similar but less intense staining rea
ctions at the same sites. Eserine-treated sections showed no AChE acti
vity in all areas where it is usually present. The present techniques
failed to demonstrate AChE activity in the nervous tissue including th
e hypodermal nerve trunks and neuromuscular junctions of the worm. The
possible functional significance of the demonstrable enzymes was disc
ussed with respect to their location. NSE activity may be involved in
lipid metabolism, whereas AChE activity may have a role in host-parasi
te relationship.