Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
 28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Release of peroxidase from secretory cells of rat lacrimal gland upon cholinergic stimulation was studied in vitro with single lobules and isolated cells (lacrimocytes). Isolated lobules, kept in Eagle's medium, remain structurally intact and reaction product of peroxidase is confined to cisternae of rough endoplasmic reticulum, elements of the Golgi apparatus, and all secretory granules. Morphologically, exocytosis occurs by membrane fusion and discharge of granule content. The highest rate of peroxidase released from lobules is observed at 10(-4) M carbamylcholine. The specific activity of peroxidase released into the medium is fourfold higher as compared to the lobules. Release of peroxidase is suppressed by atropine when added before or after the addition of carbamylcholine. At 4 degrees C, no peroxidase release occurs upon cholinergic stimulation. The exocytotic release of peroxidase is dependent on energy supply, as indicated by substantial inhibition (at 37 degrees C) under anoxic conditions or in the presence of dinitrophenol, KCN, or carboxyatractyloside. Furthermore, the process is sensitive to colchicine and vinblastine. Isolated lacrimocytes, consiting of 95% secretory acinar cells, are prepared by digestion with collagenase, hyaluronidase, and trypsin. They retain the characteristic polarity of secretory cells in situ, and localization of peroxidase is the same as in lobules. Since isolated lacrimocytes respond to cholinergic stimulation in the same way as lobules, the receptors are not damaged by the isolation procedure and appear to be associated directly with the exocrine cell. Oxygen uptake by isolated lacrimocytes is about 14 nmol O2 X min-1 X 10(-6) cells; it is about doubled by uncoupling with dinitrophenol. Oxygen uptake rises by 20-30% above the resting rate upon cholinergic stimulation. This additional uptake is suppressed by atropine or by added cholinesterase, indicating that continuous receptor occupancy may be required for the energy demand by exocytosis. On the basis of the specific activity of peroxidase in the medium, the energy demand resulting from cholinergic stimulation is estimated to be 0.08 mumol ATP (or energy-rich phosphate bonds) per microgram of protein released from the lacrimocytes.
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PMID:Exocytosis in secretory cells of rat lacrimal gland. Peroxidase release from lobules and isolated cells upon cholinergic stimulation. 95 71

The distribution of nerve fibers containing peptides which include calcitonin gene-related peptide (CGRP), substance P (SP), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) and enzymes of tyrosine hydroxylase (TH) and acetylcholinesterase (AchE) in the lacrimal gland of the monkey (Macaca fuscata) was studied using immunohistochemical and enzymehistochemical methods. We also examined the trigeminal ganglion (TG) and superior cervical ganglion (SCG) using the same methods. All peptide- and enzyme-containing nerve fibers examined in this study were present in the lacrimal gland and a consistent distribution pattern for each substance was found. CGRP-immunoreactive (IR) nerve fibers were mainly distributed around the blood vessels in the interlobular connective tissue. The distribution pattern of SP-IR nerve fibers was similar to that of CGRP-IR nerve fibers, but they were much less in number. NPY-IR nerve fibers were observed mostly around the blood vessels and occasionally in the interstitial stroma between the acini. Numerous VIP-IR nerve fibers were found surrounding the acini, ducts and blood vessels. TH-IR nerve fibers were also been around the blood vessels and in the interstitial stroma between the acini, as were NPY-IR fibers. The highest concentration of acetylcholinesterase (AchE)-positive nerve fibers was present in the acini, ducts and blood vessels, showing a similar distribution to VIP-IR fibers. In the TG, 50% of medium and 30% of small ganglion cells were CGRP-IR cells, while 20% of medium and 25% of small ganglion cells were of the SP-IR types.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunohistochemical and enzymehistochemical studies of peptidergic, aminergic and cholinergic innervation of the lacrimal gland of the monkey (Macaca fuscata). 137 36

The origin, course and distribution of pre- and postganglionic neurons of the pterygopalatine ganglion (PPG) in the rat were studied using acetylcholinesterase staining, wheat germ agglutinin coupled to horseradish peroxidase (WGA-HRP) histochemistry and autoradiography. These methods were used in a selected and planned fashion to reveal details concerning the innervation of the lacrimal gland and portions of the eye. The PPG in rats consists of a rostral triangular portion and additional perikarya surrounding the distal part of the major petrosal nerve. Fibres from the superior cervical ganglion (SCG) reach the PPG via the inferior petrosal sinus. Application of WGA-HRP was made after transections: (1) rostral to the PPG; and (2) caudal to the PPG. The first of these applications labelled mainly fibres in the PPG; the second application labelled preganglionic parasympathetic brainstem neurons dorsolateral to the facial nucleus (i.e. the lacrimal nucleus), rostral cells in the SCG and trigeminal sensory fibres. WGA-HRP injections of the lacrimal gland, the conjunctiva and the anterior chamber of the eye all labelled cells in different parts of the PPG. This means that the PPG contains sensory and sympathetic nerve fibres and that the PPG has a topographical organisation along the rostrocaudal axis. Isotope injections of the PPG anterogradely labelled fibres passing through the ciliary ganglion that innervated the conjunctiva, the limbus and parts of the choroid.
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PMID:Pre- and post-ganglionic nerve fibres of the pterygopalatine ganglion and their allocation to the eyeball of rats. 169 65

The histochemical localization of acetylcholinesterase activity in the lacrimal gland was investigated in intact (control) and chemically sympathectomized desert rats. An intensely positive specific cholinesterase reaction was found in the thick nerve bundles distributed throughout the interlobular connective tissue septa. Thick and fine nerves were present in the vicinity of the intra- and interlobular ducts and round the glandular acini and the blood vessels. The finding that this distribution pattern did not alter in the lacrimal gland of chemically sympathectomized animals suggest that the nerves are of a parasympathetic nature.
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PMID:Cholinergic nerves in the lacrimal gland of the desert rat. 179 Mar 41

The chicken Harderian gland, the major lacrimal gland, has two major cell populations: a cortical secretory epithelium and a medullary interstitial cell population of lymphoid cells. There is an extensive acetylcholinesterase (AChE) network throughout the gland, as well as catecholamine positive fibers among the interstitial cells. There are substance P-like (SPLI) and vasoactive intestinal polypeptide-like (VIPLI) immunoreactive fibers throughout the gland. These fibers are particularly dense and varicose among the interstitial cells. The adjacent pterygopalatine ganglion complex has neuronal somata that exhibit VIPLI and were AChE-positive. This ganglion complex also contains SPLI and catecholamine-positive fibers. In regions of the ganglion, the somata appear surrounded by SPLI varicosities. Surgical ablation of the ganglion eliminated or reduced the VIPLI, AChE and catecholamine staining in the gland. The SPLI was reduced only in some regions. Ablation of the superior cervical ganglion or severance of the radix autonomica resulted in the loss of catecholamine staining in the pterygopalatine ganglion and the gland. Severance of the ophthalmic or infraorbital nerves had no effect on the VIPLI or the SPLI staining pattern in the gland.
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PMID:Neuropeptides and the innervation of the avian lacrimal gland. 274 5

Vasoactive intestinal polypeptide (VIP) is a biologically active neuropeptide found in both the peripheral and the central nervous systems. Previous studies have shown that VIP-like immunoreactive nerves are present in the uveal tissues of the human eye. The distribution of VIP-like immunoreactivity of the human lacrimal gland and sphenopalatine ganglion was studied. A lacy network of VIP-like immunoreactive nerve fibers was found in the lacrimal gland and was predominantly located along the basilar surface of the acinar epithelium and in the interstitial connective tissue of the gland. This pattern of innervation was nearly identical to the distribution of cholinesterase-positive fibers in human lacrimal glands. The VIP-like immunoreactive cell bodies were found throughout the sphenopalatine ganglion obtained at autopsy. The distribution of VIP-like immunoreactive nerves in the human lacrimal gland and sphenopalatine ganglion was generally similar to that described in mammalian and avian systems, although some differences were noted. Vasoactive intestinal polypeptide may represent an important cotransmitter or neuromodulator for the facial parasympathetic nerves that supply the eye and the lacrimal gland.
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PMID:Vasoactive intestinal polypeptide and the innervation of the human lacrimal gland. 304 45

Exocrine acinar cells possess a unique system of basally located lysosomes. Cytochemically, these lysosomes do not contain acid phosphatase, but react positively for trimetaphosphatase (C Oliver: J Histochem Cytochem 28:78, 1980). The present study extends the morphological and cytochemical characterization of these lysosomes in pancreatic, parotid, and exorbital lacrimal acinar cells from Sprague-Dawley rats and National Institutes of Health Swiss mice. The basal lysosomes are highly pleomoric in nature, and frequently appear as a system of anastomosing tubules of varying width. The lysosomes have a close morphological relationship with both the rough endoplasmic reticulum and mitochondria. In addition to trimetaphosphatase activity, the lysosomes are reactive for aryl sulfatase B, thiolacetic acid esterase, and cholinesterase. Since the cholinesterase activity could not be inhibited by specific inhibitors, this activity is most likely due to the presence of nonspecific esterases. The results of this study confirm the lysosomal nature of the basal lysosomes and underscore the necessity of using multiple enzyme activities to identify and characterize lysosomes.
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PMID:Characterization of basal lysosomes in exocrine acinar cells. 630 50

The distribution of nerves and mast cells was studied in the lacrimal glands of 3-5-, 14- and 24-month-old rats, using light microscopic histochemical and immunohistochemical techniques. In 14-month and, to a greater extent, in 24-month-old rats there were signs of chronic inflammation and patchy destruction of acinar, ductal and vascular tissue. The glands of the three different age groups contained acetylcholinesterase (AChE), vasoactive intestinal polypeptide (VIP)-, neuropeptide Y (NPY)-, calcitonin gene-related peptide (CGRP)-, tyrosine hydroxylase-, substance P- and the phosphoprotein B-50-immunoreactive nerves. B-50-immunoreactive nerves were distributed around acini, blood vessels and ducts, in a similar manner to VIP and AChE. Substance P- and CGRP-immunoreactive nerves were sparsely distributed in interlobular connective tissue and around ducts and blood vessels. Tyrosine hydroxylase- and NPY-containing nerves were found around blood vessels. The 3-5- and 14-month-old rats had a similar pattern of innervation, however, by 24 months there was a reduction in the number and intensity of immunoreactive nerves. The loss of nerves was particularly associated with damage to the gland. Mast cells were also found in the lacrimal, mostly associated with neurovascular tissue. These could be histochemically labelled with alcian blue/safranin or toluidine blue and were immunohistochemically labelled with histamine and serotonin. Substance P-, CGRP-, VIP- and NPY-immunoreactive nerves were found apposed to mast cells. A large increase in mast cells was observed in 24-month compared to 3-5-month-old rats and these were found throughout the acinar tissue. These results show that a decrease in innervation and also chronic inflammation, with mast cell infiltration, occurs in aged rats. These findings may be contributing factors to reduced tear output in aging.
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PMID:Innervation and mast cells of the rat exorbital lacrimal gland: the effects of age. 818 88

The nature of the immune response following ocular immunization with a protein and a polysaccharide and the effects such immunization have on the activities of cholinergic enzymes in the lacrimal glands of BALB/c mice were examined. Lacrimal glands are highly innervated by sympathetic and parasympathetic nerve fibres and are involved in mucosal immunity and therefore are excellent sites to study neuro-immune interactions. In this report, a T-lymphocyte-dependent protein antigen, keyhole limpet haemocyanin (KLH) and a T-lymphocyte-independent polysaccharide antigen, dextran (DEX) were administered topically to the eyes or intraperitoneally injected. Both routes of immunization produced a strong serum antibody response when KLH was the antigen. DEX, however, evoked a serum antibody response only after intraperitoneal administration. Eosin-haematoxylin staining indicated no histological abnormality or inflammatory changes in any immunized lacrimal glands, but immuno-staining revealed that only in the KLH-treated tissues were IgG-producing plasma cells discernible. Furthermore, KLH-specific antibody was also detectable using an immuno-blot assay in lacrimal glands. Polymerase chain reaction analysis with cytokine-specific primers revealed induction of interleukin-4 (lL-4) in KLH-treated lacrimal glands, but not in DEX or unimmunized tissues. Thus, the nature of the antigen seems important in the induction of the immune response in lacrimal glands. To delineate the effects that immunogenic differences might have on the activities of the cholinergic enzymes, choline acetyl-transferase (ChAT) and acetylcholinesterase (AChE) were assayed using radiolabelled substrates and measuring labelled products. Both ChAT and AChE activities were influenced following KLH immunization, while DEX had only transient effects on ChAT. This is possibly due to the fact that KLH, a protein antigen, is the effective inducer of the specific immune response in the lacrimal gland, while DEX is not. Experimental Physiology (2001) 86.2, 169-176.
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PMID:Effects of T-lymphocyte-dependent and -independent immunity on cholinergic enzyme activity in mouse lacrimal gland. 1142 31

Since the increased use of extended-wear contact lenses, Pseudomonas aeruginosa has emerged as a primary etiological agent of ulcerative keratitis. Clinical isolates have been classified into two types: cytotoxic and non-cytotoxic. This study revealed significant immune and neuro-enzymatic changes elicited by the two types of P. aeruginosa in the lacrimal gland of rats. The humoral immune response in the lacrimal gland to the non-cytotoxic strain was significantly lower than to the cytotoxic strain, possibly due to the immunogenicity of the extracellular toxin; however, the same effect was not seen in the serum. Choline acetyltransferase and acetylcholinesterase are known to be responsible for synthesis and degradation of acetylcholine, respectively, binding receptors on acini and plasma cells, modulating their activity, and constituting the principle regulator of tear secretion. Following infection, neuro-enzyme activities were significantly modified to reduce the concentration of acetylcholine and therefore potentially reduce secretion from the glands. The data lead to the hypothesis that P. aeruginosa may have the potential to reduce the protective barrier provided by the lacrimal gland to benefit pathogenicity. It was also observed that the neuro-enzyme response of the lacrimal glands of uninfected eyes of the test animals was the same as that of infected eyes, implying that the signal may be relayed by common lymphoidal tissue or the central nervous system and a measurable response returned to both eyes.
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PMID:Pseudomonas aeruginosa corneal infection affects cholinergic enzymes in rat lacrimal gland. 1179 44


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