PNMT

Phenylethanolamine N-methyltransferase (EC 2.1.1.28) (PNMTase) (Noradrenaline N-methyltransferase) [PENT]

Publications[править]

Age-related changes of dopamine, noradrenaline and adrenaline in adrenal glands of mice.

Adolescent alcohol exposure alters the central brain circuits known to regulate the stress response.

Ontogeny of the expression of catecholamine synthesising enzymes in the female porcine median eminence arcuate nucleus complex (MEARC).

развернуть

Immunohistochemical localization of nNOS in the head kidney of larval and juvenile rainbow trout, Oncorhynchus mykiss.

развернуть

Postnatal development of catecholamine inputs to the paraventricular nucleus of the hypothalamus in rats.

PubMed

Full text

Adrenergic and noradrenergic neural projections to the paraventricular nucleus of the hypothalamus (PVN) contribute importantly to viscerosensory modulation of pituitary hormone secretion. Immaturity of ascending catecholamine pathways may partially underlie the documented hyporesponsiveness of PVN neurosecretory cells to certain interoceptive stimuli in rats during the first few weeks of postnatal development. To explore this possibility, the present study compared the distribution and number of dopamine-beta-hydroxylase (DBH)- and phenylethanolamine-N-methyltransferase (PNMT)-positive neurons projecting to the PVN in newborn and adult rats. In addition, a quantitative analysis of DBH- and PNMT-immunoreactive fibers in the medial parvocellular subnucleus, dorsal division (PVNmpd) and posterior magnocellular subnucleus, lateral division (PVNpml) was performed in adult rats and in developing rats on postnatal day (P)1, P7, P14, and P21. The numbers of PVN-projecting neurons in the A1, C1, A2/C2, C3, or A6 catecholamine cell groups were similar in newborn and adult rats, as were the proportions of PVN-projecting neurons in each region that were PNMT-positive. However, fewer PVN-projecting neurons in the C1 and C3 regions expressed DBH immunolabeling in newborn rats compared to adults. DBH immunolabeling increased progressively in the PVNmpd and PVNpml between postnatal days P1 and P21, when adult-like levels were achieved. Conversely, PNMT immunolabeling in the same PVN subdivisions was most dense at P1, gradually decreasing to adult-like levels by P21. These dynamic developmental changes in catecholamine synthetic enzyme immunolabeling densities in the PVN may reflect functional changes in noradrenergic and adrenergic signaling capacity in rats during the first few weeks of postnatal development.

MeSH Terms

Aging
Animals
Animals, Newborn
Axonal Transport
Axons
Brain Stem
Catecholamines
Cell Count
Cholera Toxin
Dopamine beta-Hydroxylase
Female
Fluorescent Dyes
Hypothalamo-Hypophyseal System
Immunohistochemistry
Male
Neural Pathways
Neurosecretion
Neurosecretory Systems
Paraventricular Hypothalamic Nucleus
Phenylethanolamine N-Methyltransferase
Rats
Rats, Sprague-Dawley

развернуть

Immunohistochemical and morphological characterization of spontaneously occurring pheochromocytomas in the aging mouse.

развернуть

The number of noradrenergic and adrenergic neurons in the brain stem does not change with age in male Sprague-Dawley rats.

развернуть

Expression of GAP-43 (neuromodulin) during the development of the rat adrenal gland.

PubMed

The 'growth-associated protein', GAP-43 was originally considered to be a neuron-specific protein associated with plasticity. However, we have recently shown that GAP-43 is expressed by noradrenergic, but not by adrenergic chromaffin cells in the adult rat adrenal gland. In this study, we examine the expression of GAP-43 during embryonic and post-natal development of the adrenal gland using immunohistochemical techniques. In parallel, antibodies directed against two neuroendocrine markers, the catecholamine-synthesizing enzymes, tyrosine hydroxylase (TH) and phenylethanolamine N-methyltransferase (PNMT) were employed to permit identification of the developing chromaffin cell phenotypes. At embryonic day 15.5, GAP-43 was predominately localized in sympathoadrenergic precursor cells in the extra-adrenal blastema, and also in nerve fibers within the adrenal gland. At later embryonic stages, GAP-43 was expressed by nearly all intra-adrenal chromoblasts. Two subsets of chromoblasts can be distinguished even at early stages. A strong GAP-43-positive immunoreaction was observed in those chromoblasts organized in a few large compact clusters which weakly expressed TH and did not express PNMT. A generally weaker GAP-43 immunoreaction was observed in a second type of intra-adrenal chromoblasts which were organized in small isolated groups and characterized by a PNMT-positive, and strong TH-positive immunoreactivity. GAP-43 immunoreactivity was still associated with many PNMT-positive adrenergic chromoblasts at birth, but decreased to undetectable levels during the first post-natal week. By the second post-natal week, GAP-43 was restricted, as in the adult, to noradrenergic chromaffin cells which expressed TH, but not PNMT, in addition to nerve fibers and their associated glial cells in the gland. An immunoblot analysis confirmed a decrease in GAP-43 protein during the post-natal period. In agreement with these observations, a three-fold decrease in GAP-43 mRNA in the adrenal gland was measured between late embryogenesis and the second post-natal week. During development, the spatiotemporal expression of GAP-43 suggests a possible role in the migration and aggregation of chromaffin cell precursors into the medullary region of the adrenal gland.

MeSH Terms

Adrenal Glands
Aging
Animals
Blotting, Western
DNA Primers
Embryo, Mammalian
Embryonic and Fetal Development
Fluorescent Antibody Technique
GAP-43 Protein
Gene Expression
Gestational Age
Growth Substances
Immunohistochemistry
Membrane Glycoproteins
Nerve Tissue Proteins
Phenylethanolamine N-Methyltransferase
Polymerase Chain Reaction
RNA, Messenger
Rats
Rats, Wistar
Tyrosine 3-Monooxygenase

развернуть

Regional changes in phenylethanolamine-N-methyltransferase of rat brain during development.

развернуть

An epinephrine-containing pathway in avian spinal cord: development and localization.

развернуть

[Asymmetrical content of dopamine-beta-hydroxylase and phenylethanolamine-N-methyltransferase in the adrenals of spontaneously hypertensive and normotensive Wistar-Kyoto rats].

развернуть

Identification of epinephrine and phenylethanolamine N-methyltransferase activity in rat retina.

развернуть

Immunohistochemical and biochemical study on the development of the noradrenaline- and adrenaline-storing cells of the adrenal medulla of the rat.

PubMed

Full text

The pre- and postnatal development of the adrenal medulla was examined in the rat by immunohistochemistry and by assay of catecholamines. Immunohistochemistry involved the use of antibodies to noradrenaline (NA), adrenaline (A) and the biosynthesizing enzymes dopamine beta-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT). Adrenal glands were obtained from animals from the 16th day of gestation to the 7th postnatal day at daily intervals, and at the 14th postnatal day, and from adult rats. Tissues were fixed in ice-cold, 4% paraformaldehyde, buffered at pH 7.3. Cryostat sections (7 microns) were stained with the indirect immunofluorescence technique. Adrenals from the same developmental stages were assayed for the presence of DA (dopamine), NA and A by ion-pair reversed-phase liquid chromatography with electrochemical detection. In adult adrenals the majority of the medullary cells (approximately 80%) were highly immunoreactive to A and moderately immunoreactive to NA. They also showed immunoreactivity to both DBH and PNMT, i.e., they are synthesizing and storing A. The remaining cell clusters were only stained by antibodies to DBH and NA (NA-synthesizing and -storing cells). These findings correlate well with the relative concentrations of A and NA as determined by assay. Three developmental phases could be distinguished. In the first phase, the 16th and 17th prenatal day, medullary cells were only immunoreactive to DBH and NA, and only very small amounts of A as compared to NA were found. During the second period, from the 18th prenatal day to 2 or 3 days after birth, all medullary cells were immunoreactive to DBH, NA, PNMT and A, and during this phase the adrenaline concentration increased daily and became the predominant amine on the 20th day of gestation. Adrenaline represented 75% of total catecholamine on the 1st to 3rd day after birth. The third phase started at the 2nd or 3rd postnatal day and was characterized by the presence of an increasing number of medullary cells solely immunoreactive to DBH and NA, hence synthesizing and storing NA. The remaining cells were immunoreactive to DBH, NA, PNMT and A. Postnatally, the relative concentration of A continued to rise reaching 79% by the 4th postnatal day. These results indicate that initially the adrenal medullary cells are synthesizing and storing almost exclusively NA.(ABSTRACT TRUNCATED AT 400 WORDS)

MeSH Terms

Adrenal Medulla
Aging
Animals
Chromaffin System
Dopamine beta-Hydroxylase
Epinephrine
Fluorescent Antibody Technique
Gestational Age
Histocytochemistry
Norepinephrine
Phenylethanolamine N-Methyltransferase
Rats
Rats, Inbred Strains

развернуть

Expression and development of phenylethanolamine N-methyltransferase (PNMT) in rat brain stem: studies with glucocorticoids.

PubMed

Full text

To study the differentiation of adrenergic (epinephrine-synthesizing) neurons in brain, the initial appearance and ontogeny of phenylethanolamine N-methyltransferase (PNMT), a specific marker of the adrenergic phenotype, were studied with immunocytochemistry and catalytic assay. The appearance of immunoreactivity to dopamine beta-hydroxylase (DBH-IR), an enzyme common to the noradrenergic and adrenergic phenotypes, was also studied. DBH-IR was initially observed on embryonic Day 13 (E13) in cells located on the ventrolateral floor and wall of the rhombencephalon. A day later (E14), PNMT-IR cells and PNMT catalytic activity were observed in the rhombencephalon suggesting that, as in the adrenal gland, noradrenergic expression precedes adrenergic expression. The PNMT-IR cells were presumed to be precursors of C1 neurons since they were located in the ventrolateral medulla oblongata. Cells located in the wall of the medulla which appeared to be migrating ventrally to the C1 group also contained PNMT-IR. On E15, cells which had PNMT-IR processes coursing through the germinal zone were observed dorsally near the fourth ventricle. Although the location of the C1 cell group was apparent when PNMT was initially expressed, the dorsal C2 and C3 adrenergic cell groups were not evident until late in gestation on E19. Even in the term embryo there appeared to be PNMT-IR cells which had not yet reached their final destination. On E14 and E15, PNMT-IR cells were also observed on the floor of the pons just rostral to the pontine flexure. However, these were not observed in older embryos, suggesting that transient expression of PNMT occurs in brain, as well as in the periphery. To determine whether glucocorticoids regulate brain PNMT, we examined the effects of altered glucocorticoid levels. In contrast to PNMT in the sympathetic nervous system, PNMT activity in medulla oblongata was not affected in neonates or adults by the decrease in glucocorticoids following adrenalectomy or hypophysectomy. Conversely, elevation of glucocorticoids by hormonal treatment did not alter PNMT in neonates. Notably, however, treatment of pregnant rats with dexamethasone on E18-E21, but not earlier, increased PNMT activity in the fetal brain stem. These observations suggest that PNMT expression and development is regulated by different factors in cells derived from neural crest and tube. PNMT is expressed earlier in brain than in adrenal and sympathetic ganglia. Further, the development of PNMT in the periphery, but not in the brain, is dependent on maintenance of physiological levels of glucocorticoids.(ABSTRACT TRUNCATED AT 400 WORDS)

MeSH Terms

Adrenalectomy
Aging
Animals
Brain Stem
Corticosterone
Dexamethasone
Female
Fluorescent Antibody Technique
Ganglia, Sympathetic
Glucocorticoids
Hydrocortisone
Medulla Oblongata
Phenylethanolamine N-Methyltransferase
Pregnancy
Rats

развернуть

Adrenal phenylethanolamine-N-methyltransferase activity in the young rat: influence of thyroid hormones and insulin-induced hypoglycemia.

развернуть

Evidence for discrete alterations in central cardiovascular catecholamine and neuropeptide Y immunoreactive neurons in aged male rats and in genetically hypertensive male rats of the Lyon strain.

PubMed

Full text

A computer-assisted morphometrical and microdensitometrical analysis has been performed on cardiovascular noradrenaline (NA), adrenaline (A) and neuropeptide (Y (NPY) neurons in adult and 24-month-old male rats and on hypotensive (LL), normotensive (LN) and hypertensive (LH) male rats of the Lyon strain using the indirect immunoperoxidase procedures. It was found that in NPY/phenylethanolamine-N-methyltransferase (PNMT) costoring neurons of the CI area of the rostral medulla oblongata NPY-like immunoreactivity showed a more marked reduction than the PNMT immunoreactivity. Furthermore, within the parvocellular part of the paraventricular hypothalamic nucleus. NPY immunoreactive nerve terminal profiles were much more affected than the PNMT immunoreactive profiles during aging as revealed by a marked reduction in the number of profiles and by a marked reduction of absorbency values in the microdensitometrical analysis. Thus, in the NPY/PNMT costoring neurons of the A C1 group of the ventrolateral medulla projecting, for example, to the hypothalamus, the peptide transmission line may have a special vulnerability to the aging processes which may contribute to the development of hypertension in old people in view of a vasodepressor role of many central NPY/PNMT neurons. An extensive morphometrical and microdensitometrical analysis of the various catecholamine (CA) cell groups of the medulla oblongata of the LL, LN and LH rats of the Lyon strain was performed. In a comparison between LL and LH rats the A2 cell group of the LH strain showed a trend for an increase in the mean tyrosine hydroxylase (TH) immunoreactive cell body area and the C3 group showed a significant increase in the number of PNMT immunoreactive profiles.(ABSTRACT TRUNCATED AT 250 WORDS)

MeSH Terms

Aging
Animals
Catecholamines
Densitometry
Hypertension
Immunoenzyme Techniques
Male
Medulla Oblongata
Neurons
Neuropeptide Y
Phenylethanolamine N-Methyltransferase
Rats
Rats, Inbred Strains

развернуть

Sex- and age-related changes in catecholamine metabolism and release of rat adrenal gland.

развернуть

Adrenergic expression in the rat adrenal gland: multiple developmental regulatory mechanisms.

развернуть

Presumptive adrenergic neurons containing phenylethanolamine N-methyltransferase immunoreactivity in the medulla oblongata of neonatal swine.

PubMed

Full text

Given the importance of the swine (Sus scrofa) as an animal model for human development, physiology and disease, neurons containing the epinephrine-synthesizing enzyme, phenylethanolamine N-methyltransferase (PNMT), were mapped in the medulla oblongata of neonatal swine as a first step in identifying their roles in central autonomic control. Neurons were labeled immunocytochemically by using an antiserum to PNMT raised in rabbits against trypsin-treated enzyme purified from the bovine adrenal gland. The general regional organization of neurons expressing PNMT (-like) immunoreactivity (ir) in the neonatal swine was similar to data obtained in other species and, in some aspects, more closely resembled the pattern observed in the primate brain. Immunolabeled cells appeared to be more abundant and caudally more extensive than observed in other adult animals. PNMT-immunoreactive (ir) neuronal somata, however, were largely confined to the reticular formation in the ventrolateral quadrant and the nucleus tractus solitarii (NTS) and more restricted in distribution than those expressing tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (D beta H)-ir on serial transverse sections. A close correspondence was observed between the distributions of TH- and PNMT-ir neurons and processes throughout the C1 and C2 areas. However, in the C1 and C3 regions TH-ir neurons outnumbered those containing D beta H and PNMT-ir. In contrast, cell groups enriched in PNMT-ir neurons and processes were characterized by relatively weak D beta H-ir. In the ventrolateral medulla (VLM), PNMT-ir cell bodies were concentrated rostrally and extended from the caudal pole of the facial nucleus to a level posterior to the calamus scriptorius. The rostral VLM was characterized by an admixture of bipolar and multipolar primarily medium-diameter immunostained neurons. A prominent cell column (condensation) organized ventromedially to the nucleus ambiguus pars compactus (NAc). A loosely organized cluster bordered the lateral aspect of the special visceral efferent column; another smaller aggregate was located in the ventromedial reticular formation adjacent to the inferior olive. At middle medullary levels, PNMT-ir neurons formed two distinct subgroups (dorsal and ventral) interrupted by a band of precerebellar relay neurons that extended between the medial and lateral limbs of the lateral reticular nucleus of Walberg. At obex, the dorsal cell group formed a diagonal array and assumed a position dorsal and dorsolateral to the medial limb of LRN. This group was distinguished by bipolar neurons with axes of orientation directed perpendicularly to the majority of neurons in the rostal VLM or those lying near the caudal ventromedullary surface.(ABSTRACT TRUNCATED AT 400 WORDS)

MeSH Terms

Aging
Animals
Animals, Newborn
Dopamine beta-Hydroxylase
Epinephrine
Immunohistochemistry
Medulla Oblongata
Neurons
Phenylethanolamine N-Methyltransferase
Swine
Tyrosine 3-Monooxygenase

развернуть

Expression of cell adhesion molecules and catecholamine synthesizing enzymes in the developing rat adrenal gland.

PubMed

Full text

Cell adhesion molecules play a major role in determining tissue architecture during histogenesis. This immunocytochemical study of the adrenal gland examines the embryonic and early postnatal cellular expression of two neural cell adhesion molecules, NCAM and L1, which are widely expressed in brain and have been found also to be expressed in the adult rat adrenal gland. In parallel, antibodies directed against two neuroendocrine cell markers, tyrosine hydroxylase and phenylethanolamine N-methyltransferase, were employed to verify the phenotypic nature of developing chromaffin cells in order to correlate cell adhesion molecule expression with the state of chromaffin cell differentiation. NCAM was found to be expressed by chromoblasts within extra-adrenal blastema (i.e. before their migration into the cortical primordium) at the 16th day of embryonic life. It continued to be expressed by all developing chromaffin cells after their infiltration into the developing adrenal gland at all ages. L1 was also expressed by chromoblasts in extra-adrenal sites, but was found only in a subpopulation of chromaffin cells within the cortical primordium from the 16th embryonic day onwards. Those chromoblasts which expressed L1 constituted relatively large compact cell clusters within the gland at this stage, while intra-adrenal chromaffin cells not expressing L1 were dispersed in small cell groups. L1 was also strongly expressed by nerve fibres (and their surrounding Schwann cells) which appeared to innervate cell groups as early as the 16th embryonic day. Both extra- and intra-adrenal chromoblasts expressed tyrosine hydroxylase, but the large L1-positive cell aggregates were less intensely immunoreactive for tyrosine hydroxylase than were cells in small groups. PNMT expression was restricted to L1-negative intra-adrenal chromoblasts present in small groups. Ultrastructural observations demonstrated that cells expressing L1 contained few secretory granules at the 18th embryonic day. It is concluded from these data that these chromoblasts are the precursors of the noradrenergic cells found in the mature gland. In addition, the arrangement of noradrenergic chromaffin cells in the form of homotypic cell groups throughout the course of histogenesis of the adrenal medulla is likely to be a direct consequence of the exclusive co-expression of both NCAM and L1 by this subpopulation of maturing chromaffin cells.

MeSH Terms

Adrenal Glands
Aging
Animals
Cell Adhesion Molecules
Cell Adhesion Molecules, Neuronal
Fluorescent Antibody Technique
Gestational Age
Microscopy, Immunoelectron
Models, Biological
Phenylethanolamine N-Methyltransferase
Rats
Tyrosine 3-Monooxygenase

развернуть

Activity of some enzymes which synthesize and metabolize catecholamines in the brain and peripheral organs in developing rats.

PNMT

Publications[править]

Навигация