Immunoreactivities (IR) for catecholamine-synthesizing enzymes tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DbetaH), phenylethanolamine N-methyl transferase (PNMT), serotonin-synthesizing enzyme tryptophan hydroxylase, and neuropeptide Y were investigated in the intrinsic cardiac nervous system of 27-40-day-old rats using fluorescent immunohistochemistry. Individual neurons were identified by the general neuronal marker protein gene product 9.5. The presence of DbetaH and PNMT in the atrial specimens was verified using reverse transcriptase-polymerase chain reaction. Two types of catecholamine-handling intrinsic ganglion neurons were observed: small intensely fluorescent (SIF) cells and large-diameter neurons. SIF cells exhibited TH- and tryptophan hydroxylase-IR, but they were not positive for DbetaH. In contrast, large-diameter intrinsic TH-positive neurons, showing in majority also NPY-IR, displayed also DbetaH- and PNMT-IR, thus indicating the capacity for the synthesis of norepinephrine and epinephrine, respectively. In conclusion, the SIF cells are most probably dopaminergic and serotonergic neurons, whereas large-diameter intrinsic cells seem to represent a subpopulation of norepinephrine- and/or epinephrine-secreting neurons.

• MeSH
• dopamin-beta-hydroxylasa genetika   metabolismus   MeSH
• fenylethanolamin-N-methyltransferasa genetika   metabolismus   MeSH
• imunohistochemie MeSH
• katecholaminy metabolismus   MeSH
• krysa rodu Rattus MeSH
• messenger RNA metabolismus   MeSH
• nervový systém - fyziologické jevy MeSH
• neurony fyziologie   MeSH
• neuropeptid Y metabolismus   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• potkani Wistar MeSH
• srdce inervace   MeSH
• tyrosin-3-monooxygenasa metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dopamin-beta-hydroxylasa MeSH
• fenylethanolamin-N-methyltransferasa MeSH
• katecholaminy MeSH
• messenger RNA MeSH
• neuropeptid Y MeSH
• tyrosin-3-monooxygenasa MeSH

The developmental pattern and distribution of peptide-containing neurons in the rat heart right atrium has been studied by indirect immunofluorescence. Antibodies against neuropeptide Y (NPY), substance P (SP), and vasoactive intestinal polypeptide (VIP) were applied to whole-mount stretch preparations of the right atria from hearts of newborn to 40 day-old animals. NPY-like immunoreactivity (L1) was compared with the synaptic vesicle marker SV2 in double immunoincubation studies. The distribution of immunofluorescence was studied by confocal laser scanning microscopy. NPY-L1 and SP-L1 were present throughout the atria already at birth, in contrast to VIP-L1 that was observed at day 10. The postnatal changes of innervation were basically quantitative, with an increase in density of nerve fibres and number of varicosities, while the basic pattern of innervation was essentially established during the first 1-10 days. NPY- and SP-positive bundles of fibres appeared to enter the right atrium along the superior caval vein, having extrinsic origins. Nerve fibres with NPY-L1 colocalized in most nerve terminals with SV2-L1, and showed a developmental pattern similar to that observed for adrenergic neurons earlier. These NPY/SV2 positive fibres probably represent the extrinsic NPY innervation. In addition, NPY-L1 was identified in large intrinsic nerve cells bodies located near the atrioventricular (AV) region. Most of the VIP-L1 was observed in short nerve fibres originating in intrinsic VIP-positive cell bodies, but a few apparently extrinsic VIP-positive fibres were found, probably representing preganglionic parasympathetic neurons. SP in the atria was probably of extrinsic (sensory) origin and no nerve cell bodies with SP-L1 were detected. The results show that the peptidergic innervation in the developing rat right atrium involves both extrinsic and intrinsic peptidergic neurons which may participate in the regulation of neurotransmission in local neuronal circuits.

• MeSH
• fluorescenční protilátková technika nepřímá MeSH
• konfokální mikroskopie MeSH
• krysa rodu Rattus MeSH
• neurony chemie   cytologie   metabolismus   MeSH
• neuropeptid Y analýza   MeSH
• neuropeptidy analýza   MeSH
• novorozená zvířata MeSH
• potkani Sprague-Dawley MeSH
• srdeční síně cytologie   růst a vývoj   zranění   MeSH
• substance P analýza   MeSH
• techniky in vitro MeSH
• vazoaktivní intestinální peptid analýza   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• neuropeptid Y MeSH
• neuropeptidy MeSH
• substance P MeSH
• vazoaktivní intestinální peptid MeSH