Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.14.16.2 (tyrosine hydroxylase)
 14,760 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunohistologic localization of tyrosine hydroxylase (TOH), dopamine-beta-hydroxylase (DBH) and selected neuropeptides (vasoactive intestinal polypeptide, gastrin-releasing peptide (GRP)/bombesin, substance P, Leu-enkephalin, Met-enkephalin, dynorphin B, neuropeptide Y (NPY), somatostatin) was used to investigate the innervation of the small bowel in a rat model of diabetic autonomic neuropathy. Paravascular mesenteric nerves (extrinsic) and intramural nerves of chronically (12-18 month) diabetic rats were characterized by the presence of numerous, markedly swollen dystrophic axons which stained intensely for TOH and DBH. The peptidergic complement of axons, however, showed no evidence of comparable dystrophic axonopathy.
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PMID:Effects of chronic experimental streptozotocin-induced diabetes on the noradrenergic and peptidergic innervation of the rat alimentary tract. 290 98

We have previously shown that stimulation of the preganglionic cervical sympathetic trunk leads to an acute increase in tyrosine hydroxylase (TyrOHase) activity in the rat superior cervical ganglion. This increase appears to be mediated in part by acetylcholine and in part by a second neurotransmitter. As a first step in an attempt to determine the identity of this noncholinergic transmitter, we have examined the ability of a number of neuropeptides to increase ganglionic TyrOHase activity in vitro. Secretin and vasoactive intestinal peptide (VIP) both stimulated TyrOHase activity, whereas angiotensin II, bombesin, bradykinin, cholecystokinin octapeptide, glucagon, insulin, luteinizing hormone-releasing hormone, [D-Ala(2), Met(5)]enkephalinamide, motilin, neurotensin, somatostatin, and substance P produced no effects. Secretin produced a significant increase in TyrOHase activity at 1 nM and a maximal elevation at 0.1 muM. VIP produced a significant increase at 0.1 muM and a near maximal effect at 10 muM. Although secretin was about 2 orders of magnitude more potent than VIP, it produced a significantly smaller maximal increase in enzyme activity. Incubation of ganglia with both secretin (10 muM) and VIP (10 muM) produced an increase in TyrOHase activity that was not significantly different from that produced by VIP alone. The stimulatory effects of secretin and VIP were reversible within minutes after removal of the peptides. Neither incubation of intact ganglia with the cholinergic antagonists hexamethonium and atropine nor prior decentralization of ganglia altered the response to the peptides. Thus, the data demonstrate that secretin and VIP acutely increase TyrOHase activity in the superior cervical ganglion and suggest that they produce this effect by acting directly on ganglionic neurons. It remains to be determined whether secretin or VIP or a related peptide is released during preganglionic nerve firing and whether one or more of these peptides is responsible for the noncholinergic elevation of TyrOHase activity produced by preganglionic nerve stimulation.
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PMID:Secretin and vasoactive intestinal peptide acutely increase tyrosine 3-monooxygenase in the rat superior cervical ganglion. 613 May 26

Plasma gonadotropins, prolactin and hypothalamic tyrosine hydroxylase (TH) activity were evaluated at 15 and 30 min after third ventricular injection of bombesin at doses of 100 or 1000 ng and secretin at doses of 1000 and 5000 ng in ovariectomized (OVX) unanesthetized rats. Bombesin had no effect on plasma gonadotropin levels. Intraventricular injection of either 100 or 1000 ng dose of bombesin significantly suppressed prolactin levels with parallel elevation in hypothalamic TH activity and there appears to be no dose response relationship. Secretin at 1000 ng dose, significantly lowered plasma LH and PRL levels and elevated hypothalamic TH activity whereas a 5000 ng dose increased PRL concentrations but had no effect on gonadotropin levels and hypothalamic TH activity. Bombesin appears to be a potent inhibitor of PRL release in OVX, conscious rats and this effect may be mediated via hypothalamic dopamine. Lower dose of secretin appears to inhibit PRL release by possibly activating the hypothalamic dopaminergic system, while at higher dose peripheral activation results in enhanced prolactin release.
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PMID:Plasma gonadotropin, prolactin levels and hypothalamic tyrosine hydroxylase activity following intraventricular bombesin and secretin in ovariectomized conscious rats. 613 30

We have examined the ability of a number of neuropeptides to increase tyrosine hydroxylase (TH) activity in the superior cervical ganglion in vitro. Secretin and vasoactive intestinal peptide (VIP) both increased TH activity, whereas angiotensin II, bombesin, bradykinin, cholecystokinin octapeptide, insulin, luteinizing hormone-releasing hormone, [D-Ala2, Met5]enkephalinamide, motilin, neurotensin, somatostatin, and substance P produced no effects. Secretin and VIP increased TH activity with an EC50 of 5 nM and 0.5 microM, respectively. The effects of these peptides were not altered by prior decentralization of the ganglia, by addition of hexamethonium (3 mM) and atropine (6 microM), or by lowering the concentration of calcium in the medium to 0.1 mM. Addition of carbachol (3 microM) potentiated the effects of both secretin and VIP on TH activity. Several gastrointestinal peptides with structural similarities to secretin and VIP were examined for their ability to increase TH activity. Glucagon, gastric inhibitory peptide and human pancreatic tumor growth hormone-releasing factor produced no effect at a concentration of 10 microM, while PHI increased enzyme activity.
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PMID:Acute stimulation of ganglionic tyrosine hydroxylase activity by secretin, VIP and PHI. 614 16

Peptide, 5-hydroxytryptamine (5-HT)-, tyrosine hydroxylase (TOH)-, and glial fibrillary acidic protein (GFAP)-like immunoreactivity was studied in the optic tectum of Rana pipiens. Peroxidase-antiperoxidase and indirect immunofluorescence single- and double-labeling methods were used to compare differential laminar distribution of each of these substances. Substance P (SP), leucine-enkephalin (LENK), cholecystokinin octapeptide (CCK8), bombesin (BOM), avian pancreatic polypeptide (APP), and possibly neurotensin display unique individual patterns of laminar distribution of processes and cell bodies throughout the tectum. A correlative analysis of the topographical distribution of SP, LENK, BOM, and APP on the basis of double-labeled sections shows a precise laminar segregation of these substances. Vasoactive intestinal peptide-, beta-endorphin-, and ranatensinlike immunoreactivity is consistently absent from our material. 5HT- and TOH-like immunoreactivity discloses a reticular array of fibers without clear evidence of laminar organization. This peptide-like laminar organization is particularly elaborate throughout the superficial neuropil of the optic tectum, the major retinorecipient zone. The pattern of lamination demonstrated in the present study differs in several important features from that previously described on the basis of several histological methods. The cells of origin of processes (axons and/or dendrites) in the superficial tectal neuropil may be either intrinsic or extrinsic to the tectum. Special reference is made to conflicting evidence regarding the possibility of a retinal contribution to peptide-like tectal lamination.
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PMID:Laminar organization of peptide-like immunoreactivity in the anuran optic tectum. 619 80

The endocrine cells and nerves of the respiratory tract of the reptile Podarcis hispanica were investigated by immunocytochemistry under light microscopy. Immunoreactivities were more numerous in the lung than in the trachea. In the tracheal epithelium, endocrine cells immunoreactive to PHI, PYY, and Leu-enkephalin were detected, while immunoreactivity to serotonin, calcitonin, CGRP, PHI, and Leu-enkephalin was found in pulmonary endocrine cells. Numerous nerve fibers positive to NSE, PGP9.5, chromogranin, tyrosine hydroxylase, calcitonin, CGRP, bombesin, substance P, VIP, NPY, and PYY were found in the lungs. In addition, neurons positive to NSE and PGP9.5 were also found. Immunoreactivities to PHI and PYY in cells and to NSE, PGP9.5, chromogranin, tyrosine hydroxylase, calcitonin, CGRP, and PYY in nerves, were reported first in the respiratory system of reptiles.
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PMID:An immunocytochemical study of the respiratory system of Podarcis hispanica (Reptilia). 753 37

Immunohistochemical methods were used to study the developing peptidergic innervation of the human fetal prostate gland in a series of specimens ranging in gestational age from 13 to 30 wk. The overall innervation of each specimen was visualised using protein gene product 9.5 (PGP), a general nerve marker. The onset and development of specific neuropeptide-containing subpopulations were investigated using antisera to neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), substance P (SP), calcitonin gene-related peptide (CGRP), bombesin (BOM), somatostatin (SOM), leu-enkephalin (l-ENK) and met-enkephalin (m-ENK). In addition the occurrence and distribution of presumptive noradrenergic nerves was studied using antisera to dopamine-beta-hydroxylase (D beta H) and tyrosine hydroxylase (TH). At 13 wk numerous branching PGP-immunoreactive (-IR) nerves were observed in the capsule of the developing prostate gland and surrounding the preprostatic urethra but the remainder of the gland was devoid of nerves. The majority of nerves in the capsule contained D beta H and TH and were presumed to be noradrenergic in type while other nerves (in decreasing numbers) contained NPY, l-ENK, SP and CGRP. Nerves associated with the preprostatic urethra did not contain any of the neuropeptides under investigation. At 17 wk the density of nerves in the capsule had increased and occasional m-ENK-, VIP- and BOM-IR nerve fibres were also observed. In addition PGP, D beta H-, TH-, NPY- and l-ENK-IR nerves occurred in association with smooth muscle bundles which at 17 wk were present in the outer part of the gland. Occasional PGP-IR nerves were also present at the base of the epithelium forming some of the prostatic glands. At 23 wk some of the subepithelial nerves showed immunoreactivity for NPY, VIP or l-ENK. At 26 wk smooth muscle bundles occurred throughout the gland and were richly innervated by PGP, D beta H and TH-IR nerves while a less dense plexus was formed by NPY- and l-ENK-IR nerves together with a few m-ENK-IR nerves. Occasional smooth muscle-associated varicose nerve fibres showed immunoreactivity for SP, CGRP, VIP or BOM although the majority of these types of nerve formed perivascular plexuses. Also at 26 wk numerous varicose nerve fibres were observed in association with the prostatic acini, the majority of such nerves containing NPY with a few showing immunoreactivity to VIP, l-ENK, SP or CGRP.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Development of peptide-containing nerves in the human fetal prostate gland. 759 78

The distribution of neuropeptide Y, substance P, vasoactive intestinal polypeptide, Leu5-enkephalin, bombesin/gastrin-releasing peptide, calcitonin gene-related peptide, somatostatin, cholecystokinin and catecholamine synthesizing enzymes, tyrosine hydroxylase and dopamine-beta-hydroxylase was studied immunohistochemically in nerve fibres supplying the bovine vagina and uterus. The nerves containing tyrosine hydroxylase or dopamine-beta-hydroxylase and neuropeptide Y-immunoreactivity were particularly numerous in both organs. Substance P, vasoactive intestinal polypeptide and Leu5-enkephalin-containing nerves were less numerous whereas somatostatin and calcitonin gene-related peptide-immunoreactive nerves occurred occasionally. Bombesin/gastrin-releasing peptide and cholecystokinin immunoreactivities were not present in nervous fibers of the bovine uterus and vagina. Generally, the immunoreactive nerve terminals, fibers, networks or nerve bundles were present below the serous membrane, between smooth muscle cells of muscular layers, around blood vessels, in the submucosal layer and below the luminal epithelium of the uterus and cervix.
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PMID:Peptidergic innervation of the bovine vagina and uterus. 777 Nov 84

The occurrence and distribution of tyrosine hydroxylase, neuropeptide Y, somatostatin, Met5-enkephalin-Arg6-Gly7-Leu8, vasoactive intestinal polypeptide, substance P, calcitonin gene-related peptide, bombesin gastrin releasing peptide and galanin were immunohistochemically studied in the perikarya and nerve fibres of the porcine coeliac-superior mesenteric ganglion of untreated juvenile pigs. Subpopulations of neurons containing immunoreactivities to tyrosine hydroxylase, neuropeptide Y, Met5-enkephalin-Arg6-Gly7-Leu8, somatostatin, vasoactive intestinal polypeptide and galanin were disclosed in the studied ganglion, whereas principal ganglionic cells were non-immunoreactive for other investigated peptides. Double-immunofluorescence and analysis of consecutive sections revealed a partial colocalization of tyrosine hydroxylase and neuropeptide Y, Met5-enkephalin-Arg6-Gly7-Leu8 and somatostatin, whereas immunoreactivity to vasoactive intestinal polypeptide and/or to neuropeptide Y was found in non-noradrenergic neurons in this ganglion. All of neuropeptides studied were found in nerve fibres in this ganglion. The results of this study were compared with those of previous studies performed on other species.
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PMID:Neuropeptides in the porcine coeliac-superior mesenteric ganglion. 790 96

The occurrence and co-localization of several presumed vasoactive neuropeptides, serotonin, and catecholamine-synthesising enzymes--tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (D beta H) and phenylethanolamine-N-methyltransferase (PNMT)--were investigated in perivascular nerves supplying the systemic and distributing arteries of the abdomino-pelvic arterial tree of the female pig and certain arteries supplying female reproductive organs in the cow. As revealed by single immunofluorescence, perivascular axons immunoreactive for TH, D beta H, neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), substance P (SP), calcitonin gene-related peptide (CGRP) and Leu-enkephalin (LENK) occurred in both species examined, whereas galanin-immunoreactive (GAL-IR) nerve fibres were found exclusively in the pig. PNMT-, serotonin-, dynorphin A-, alpha-neoendorphin-, bombesin- or cholecystokinin-IR nerve terminals were not observed. The following classes of perivascular nerve fibres might be distinguished in the present study: 1) noradrenergic (i.e. TH/D beta H-IR), 2) NPY-, 3) GAL- (pig only), 4) LENK-, 5) VIP-, 6) SP-, 7) VIP/NPY-, 8) SP/CGRP-, 9) SP/GAL- (pig only), 10) SP/VIP- (cow only), 11) TH/D beta H/NPY- and 12) TH/D beta H/NPY/LENK-IR. Distinct differences in the distribution of LENK- and SP-IR axons around particular parts of the studied arterial tree in individual species were also observed. The present data indicate that the abdomino-pelvic arterial tree of the pig and cow receive perivascular nerve fibres that exhibit diverse chemical codes, and that different chemical coding of perivascular nerve fibres in individual species may depend on the target organ of the particular artery.
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PMID:Existence and co-existence of vasoactive substances in nerve fibres supplying the abdomino-pelvic arterial tree of the female pig and cow. 852 81


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