The effect of Trypanosoma brucei infection of the localization of salivary gland cholinesterase in Glossina morsitans morsitans.

When salivary glands of the tsetse fly, Glossina morsitans morsitans, are stained for cholinesterase (ChE) activity, a net-like pattern of reaction product is observed surrounding each epithelial cell of the gland's secretory region. Glands infected with Trypanosoma brucei brucei show a progressive reduction in this ChE activity as the parasites develop. When the infection is mature, ChE is rarely detected in the epithelial layer but appears in the lumen of gland. The luminal ChE responds to substrates and inhibitors in the same manner as the epithelium-associated enzyme and appears to have leaked from the epithelium due to cellular damage in epithelium of the infected gland. The possible effect of glandular damage on feeding behaviour and state of health is discussed.