ABSTRACT
Non-specific cholinesterase (ChE) activity was demonstrated in the Meissner and lamellated corpuscles of rats, through light and transmission electron microscopy observations. A intense cholinesterase activity was noted in the sensory nerve endings. reaction products were present in the interlamellar spaces between neighbouring lamellae and some in caveolae of the lamella cell plasma membrane. No reaction products were observed within the axon terminals. Since the lamellaeof the sensory corpuscles contain an intense ChE activity, it was suggested that the enzyme would have a role in the function of the mechanoreceptors.
Subject(s)
Animals , Rats , Cholinesterases/metabolism , Mechanoreceptors/enzymology , Extremities , Lip , Mechanoreceptors/ultrastructure , Microscopy, Electron/methods , Mucous Membrane , Rats, Wistar , SkinABSTRACT
Cercal ablation caused a significant loss in acetylcholinesterase (AChE) activity of the cercal nerves and terminal ganglion within 12 hr while a similar reduction in enzyme activity of connectives was noticed at least one day after cercectomy. The decrease in AChE activity of the nervous tissues showed a recovery toward control levels from 20 days of unilateral cercectomy whereas the bilateral cercectomy produced a continuous and irreversible decline in enzyme activity. These localized changes in AChE activity of the abdominal nervous system of the cockroach were attributed to be regulated by the cercal sensory innervation.
Subject(s)
Acetylcholinesterase/metabolism , Animals , Mechanoreceptors/enzymology , PeriplanetaABSTRACT
A atividade de colinesterase inespecífica foi demonstrada em corpúsculos lamelares sensitivos do lábio de ratos através da microscopia óptica e eletrônica de transmissäo, utilizando o método de Karnovsky & Roots. A atividade colinesterásica estava presente no espaço interlamelar entre lamelas sucessivas, bem como no espaço entre o axônio terminal e a lamela adjacente. Produtos de reaçäo da atividade colinesterásica eram bem evidentes em algumas cavéolas da membrana plasmática da célula lamelar e em cisternas do retículo endoplasmático granular, bem como na membrana nuclear. Produtos inespecíficos de reaçäo foram detectados dentro do axônio terminal. Esses dados mostram que os corpúsculos lamelares do lábio de ratos, como outros mecanorreceptores, apresentam intensa atividade colinesterásica, a qual é associada principalmente com as células lamelares. Pode-se dizer que a histoquímica de colinesterase é útil para detectar os mecanorreceptores. A significância funcional da colinesterase em mecanorreceptores é discutida