Despite the fact that vessels have sparse cholinergic innervation, acetylcholine (ACh), the primary neurotransmitter of parasympathetic nervous system, has been commonly used in physiological experiments to assess vascular function. ACh is hydrolyzed by two cholinesterases (ChE), namely acetylcholinesterase and butyrylcholinesterase (BChE). However, little is known about these enzymes in blood vessels. The aim of the project was to characterize the expression and activity of ChE in rat aorta. As the effect of ACh on vascular tone depends on the presence of endothelium, Wistar rats were used as a model with intact endothelium and spontaneously hypertensive rats as a model of impaired endothelial function. Relative expressions of both ChE in different parts of the aorta were determined using RT-qPCR. Enzyme activities were assessed in tissue homogenates by Ellman's assay. Here we showed that both ChE are present in each part of rat aorta, while mRNA is more abundant for BChE than for AChE, irrespective of aortic compartment or genotype. Normotensive Wistar rats possess higher aortic mRNA expression and activity of BChE compared to SHR. We concluded that BChE is the dominant type of ChE in rat aorta and it might play an important role in the regulation of vascular tone., Kristína Szmicseková, Lenka Bies Piváčková, Zuzana Kiliánová, Ľubica Slobodová, Peter Křenek, Anna Hrabovská., and Obsahuje bibliografii
Derivative of 6-methyluracil, selective cholinesterase inhibitor C-547 potentiates miniature endplate currents (MEPCs) in rat external intercostal muscles (external ICM) more effectively than in internal intercostal muscles (internal ICM). Effect of the C-547 on intercostal muscles was compared with those on extensor digitorum longus (EDL) and diaphragm muscles. Half-effective concentrations for τ of MEPC decay arranged in increasing order were as follows: EDL, locomotor muscle, most sensitive = 1.3 nM, external ICM, inspiration muscle = 6.8 nM, diaphragm, main inspiration muscle = 28 nM, internal ICM, expiration muscle = 71 nM. External ICM might therefore be inhibited, similarly as the limb muscles, by nanomolar concentrations of the drug and do not participate in inspiration in the presence of the C-547. Moreover, internal ICM inhibition can hinder the expiration during exercise-induced fast breathing of C-547-treated experimental animals., K. Petrov ... [et al.]., and Obsahuje seznam literatury
Acetylcholinesterase (AChE) inhibitors represent standard treatment of Alzheimer´s disease. Cholesterol plays an important role in Alzheimer´s disease development. Because cholesterol synthesis may be inhibited by statins or bisphosphonates, we hypothesized that these drugs might possibly have an influence on cholinesterases. Moreover, we also evaluated if the cholesterol-lowering agents that cross the blood-brain barrier (e.g. simvastatin) should be more effective than those which do not (e.g. atorvastatin). Four groups of rats were orally administered simvastatin, atorvastatin, alendronate or vehicle for seven days. Thereafter, blood samples were taken and the basal ganglia, septum, frontal cortex, and hippocampus were isolated from brains for measurement of acetylcholinesterase activity. In the blood, activities of neither acetyl- nor butyrylcholinesterase were influenced by any of the applied drugs. In the brain, no significant changes in AChE activity were observed after administration of atorvastatin. Both simvastatin and alendronate significantly suppressed the activity of AChE in the frontal cortex. In conclusion, our results confirmed the hypothesis that cholesterol-modifying drugs modulate AChE activity and it is more reasonable to use a blood-brain barrier penetrating drug., Ľ. Cibičková, V. Palička, N. Cibiček, E. Čermáková, S. Mičuda, L. Bartošová, D. Jun., and Obsahuje bibliografii a bibliografické odkazy
The freely diffusible radical, nitric oxide (NO), has been assumed to act as a retrograde signaling molecule that modulates transmitter release. Acetylcholine (ACh) is known to function as a typical neurotransmitter. In the present work we have examined the presence of both transmitters (NO and ACh) and their possible relations in the rabbit spinal cord. In our experiments we have used histochemical methods for the visualization of acetylcholinesterase (AChE) and NADPH diaphorase (NADPH-d) which label neurons that express nitric oxide synthase (NOS). Both histochemical methods were performed separately or together on the same sections of the thoracic spinal cord. NADPH-d positive dark blue stained neurons were seen mostly in superficial and deep layers of the dorsal horn, preganglionic autonomic neurons and pericentral area. The presence of AChE positive amber yellow neurons was confirmed mostly in motoneurons located in the ventral horns and in neurons of the pericentral and intermediate zone. Besides the above mentioned neurons, also double-labeled neurons were found which contained both the yellow and dark blue histochemical product. Their presence was confirmed in the intermediate zone and in the pericentral area. Thus, the co-existence of NADPH-d and AChE occurred in the location of interneurons. Our observations suggest that NO may play a role in the control of cholinergic neuronal activity and that NO can be involved in the modulation of synaptic transmission., D. Kluchová, K. Schmidtová, S. Rybárová, K, Lovásová, M. Pomfy, T. Prosbová, A. Vatľak., and Obsahuje bibliografii