138,268 research outputs found
New N,N-dimethylcarbamate inhibitors of acetylcholinesterase: design synthesis and biological evaluation
A series of N,N-dimethylcarbamates containing a N,N-dibenzylamino moiety was synthesized
and tested to evaluate their ability to inhibit Acetylcholinesterase (AChE). The most active
compounds 4 and 8, showed 85 and 69% of inhibition at 50 mM, respectively. Furthermore,
some basic SAR rules were outlined: an alkyl linker of six methylene units is the best spacer
between the carbamoyl and dibenzylamino moieties; electron-withdrawal substituents on
aromatics rings of the dibenzylamino group reduce the inhibitory power. Compound 4
produces a slow onset inhibition of AChE and this is not due to the carbamoylation of the
enzyme, as demonstrated by the time-dependent inhibition assay of AChE with compound 4
and by MALDI-TOF MS analysis of trypsinized AChE inhibited by compound 4. Instead,
compound 4 could act as a slow-binding inhibitor of AChE, probably because of its high
conformational freedom due to the linear alkyl chain
Age-related changes of the noradrenergic and acetylcholinesterase reactive nerve fibres innervating the pigeon bursa of Fabricius.
Age-dependent changes in the innervation of the pigeon (Columba livia, L.) bursa of Fabricius, from hatching to 120 days of age, were studied by fluorescence-histochemical and neurochemical methods for demonstrating noradrenergic and acetylcholinesterase (AChE)-reactive nerve fibres respectively. The distribution of both nerve fibre types was largely perivascular. Furthermore, a few isolated nerve fiber profiles were observed beneath the bursal epithelium, in the interfollicular septa and in the follicular cortex. No nerve fibre profiles reaching the medulla of the lymphoid follicles were observed. In addition to nerve fibres, AChE reactive neuron-like cells were encountered within the capsule and interfollicular septa. AChE reactivity was also found in dendritic-like cells localized in the cortical and cortico-medullary border. No changes in the density of perivascular noradrenergic innervation were noticeable during the ages studied, whereas the density of AChE-reactive fibres supplying vessels reached the adult pattern at 30 days, and then remained unvaried. The density of non-perivascular nerve fiber profiles, specially the AChE reactive type, increased until 30 days, remained unchanged until 75 days and then increased with aging (90-120 days). The interrelationship between the autonomic nervous system and the immune system is discussed
Activity of cholinesterases of blood and heart in rats of different sex and age during muscular loads and hypokinesia
The activity of acetylcholinesterase (Ache) and butyrilcholinesterase (Bche) in the blood and the heart of 3 and 13 month old control male rats is considerably lower than in female rats. In 25 month old rats, no sex differences in the Ache and Bche were revealed in the heart. In 3 and 13 month old male and female rats, under conditions of muscular exercises, the Ache and Bche activity is lower, and in hypokinetic male rats -- higher than that in respective control animals. In all the rats, irrespective of sex, age, and motor conditions, Ache and Bche activity tended to decrease from the sinoatrial node to the heart apex
Use and disuse and the control of acetylcholinesterase activity in fast and slow twitch muscle of rat
The role of acetylcholinesterase (AChE) in neuromuscular transmission is relatively well established, little is known, however, of the mechanisms that regulate its synthesis and control its specific distribution in fast and slow muscle. Innervation plays an important role in the regulation of AChE and elimination of the influence of the nerve by surgical denervation results in a loss of AChE. The influences of the nerve and how they are mediated was investigated. It is suggested that muscle usage and other factors such as materials carried by axonal transport may participate in the regulation of this enzyme. The mechanisms that regulate AChE and its molecular forms in two functionally different forms are studied
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