Biomedical subjects

V Roudenok

Publications and source records attributed to V Roudenok.

7 recordsLinked to original sources

PubMed2001

Expression of vasoactive intestinal polypeptide and calcitonin gene-related peptide in human stellate ganglia after acute myocardial infarction.

Using the method of indirect immunofluorescence the distribution of vasoactive intestinal polypeptide (VIP) and calcitonin gene-related peptide (CGRP) was investigated in autopsy specimens of human stellate ganglia following acute myocardial infarction (AMI). The dramatic increase of both VIP- and CGRP-immunoreactivities in principal ganglionic neurons as well as of calcitonin gene-related peptide in perineuronal nets was revealed. It was concluded that hypoxia and myocardial ischaemia following AMI are the main inducing factors for activation of both vasoactive regulatory neuropeptide synthesis. The upregulation of VIP and CGRP expression in sympathetic ganglionic neurons may provide regulatory and trophic support to the ischaemic heart.

Autopsy↗

PubMed2001

The development of synaptophysin immunoreactivity in the human sympathetic ganglia.

Using an indirect immunohistochemical method, synaptophysin immunoreactivity (SYN-IR) has been studied in cryostat sections of stellate and thoracic ganglia in human fetuses, neonates, infants and adults. In the course of development, a progressive increase in SYN-IR in axonal terminals and around nerve cells was demonstrated. In contrast, large clusters of small intensely fluorescent (SIF) cells and paraganglionic cells increased in number in fetuses and premature neonates at 24-25 weeks. Such SIF cell clusters varied in form and often occurred at pole or subcapsular areas of sympathetic ganglia close to blood vessels or paraganglia. With increasing gestational age and during infancy, a decrease in sizes of SIF cell groups and paraganglionic cells as well as changes in their distribution were found. The results show that the amount and distribution of SYN-IR is temporally related to the maturation and functional activity of human sympathetic ganglia neurons. It was suggested that numerous SIF cells and paraganglia in human prenatal sympathetic ganglia were both indicative of incomplete cell migration and an important source of regulation of ganglionic microcirculation under the conditions of relative hypoxia and immature nervous regulation.

Adult↗

PubMed2001

Upregulation of vasoactive intestinal polypeptide (VIP) and calcitonin gene-related peptide (CGRP) expression in stellate ganglia of children with congenital cardiovascular lesions.

The distribution patterns of vasoactive intestinal polypeptide (VIP) and calcitonin gene-related peptide (CGRP) immunoreactivities (IR) in stellate ganglia of human neonates and infants with congenital heart and vascular lesions were investigated by the method of indirect immunohistochemistry. The results demonstrated upregulation of VIP and CGRP expression in principal ganglionic neurons independently of the type of lesion. It is suggested that the activation of neuropeptide synthesis in stellate ganglia is a compensatory reaction of ganglionic neurons in response to congenital cardiovascular lesions, in regulation of heart contractility, and as a trophic influence on the ischemic myocardium. Hypoxia is the main inducing factor for the upregulation of VIP and CGRP expression in sympathetic neurons.

Autopsy↗

PubMed2001

Distribution of vasoactive intestinal polypeptide-, calcitonin gene-related peptide-, somatostatin- and neurofilament-immunoreactivities in sympathetic ganglia of human fetuses and premature neonates.

The distribution patterns of vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), somatostatin (SOM) and neurofilament (NF) immunoreactivities (IR) were studied in the stellate ganglia of human fetuses and neonates at 24-26 weeks gestation. Sizeable populations with some quantitative variations of VIP-, CGRP- and SOM immunoreactive nerve cells were detected in all ganglia studied. In marked contrast, neurofilament expression was down-regulated. The upregulation of VIP, CGRP and SOM expression suggested their inductor effect on growth and differentiation neurons as well as on the development of their neurotransmitter properties. The main neuropeptides-inducing factor of sympathetic ganglia in human prenatal ontogenesis may be considered as a relative hypoxia.

Autopsy↗

PubMed2000

Calcitonin gene-related peptide (CGRP) expression in the human neonatal paravertebral ganglia.

The distribution of calcitonin gene-related peptide-immunoreactivity (CGRP-IR) in human neonatal paravertebral ganglia was demonstrated by the method of indirect immunohistochemistry. A marked population (up to 21%) of CGRP-IR neurons and varicose nerve fibres was observed. The number of calcionin gene-related peptide-immunoreactive neurons varied from ganglion to ganglion in the sympathetic trunk. In addition to its cotransmitter functions, the existence of CGRP in neonatal ganglionic nerve cells was suggested by its inductive and trophic actions on the growth and differentiation of neurons.

Calcitonin Gene-Related Peptide↗

PubMed2000

Changes in the expression of neuropeptide Y (NPY) during maturation of human sympathetic ganglionic neurons: correlations with tyrosine hydroxylase immunoreactivity.

Developmental patterns of neuropeptide Y (NPY) and tyrosine hydroxylase (TH)-immunoreactivities (IR) were investigated using the method of indirect immunohistochemistry in the stellate and thoracic sympathetic ganglia of human neonates ranging in gestational age from 24 to 27 weeks (premature group) and from 38 to 41 weeks (mature group). In the paravertebral ganglia of premature neonates a small (up to 7%) population of NPY-IR nerve cells was revealed. With the gestational age increase (a mature group), a marked elevation of the number of NPY-IR ganglionic neurons (up to 41%) was noted. In contrast, in the sympathetic ganglia of premature neonates almost all the neurons were tyrosine hydroxylase immunoreactive and any change in pattern during maturation was insignificant. The results demonstrate an age-related increase of neuropeptide Y-immunoreactivity in human paravertebral ganglia during maturation, and suggest that peptidergic co-transmission arises later in development than do the classical autonomic messengers. Adaptability of the fetus to a new external environment at birth demands a qualitatively new activity level of the autonomic nervous system, and this is provided side by side with the classical messengers noradrenaline and acetylcholine by the co-transmitter and modulating role of the neuropeptides. The appearance of neuropeptide Y in the principal sympathetic ganglionic neurons defines not only a qualitatively new level in the functional regulation of target organs at birth, but serves as an index of neonatal maturity.

Ganglia, Sympathetic↗

PubMed1999

Developmental changes in vasoactive intestinal polypeptide immunoreactivity in the human paravertebral ganglia.

Vasoactive intestinal polypeptide (VIP) belongs to the glucagon-secretin family of polypeptides and possesses numerous functions. Its existence in the mammalian central and peripheral nervous system has been widely documented. However, there are no reports on the developmental aspects of VIP-like immunoreactivity (VIP-IR) in the human postganglionic sympathetic neurons. In this study the availability and distribution of vasoactive intestinal polypeptide has been localized in human stellate ganglia neurons and nerve fibers from neonates, children and adults using the immunohistochemical method. In neonatal ganglia VIP-immunoreactive postganglionic neurons were revealed in a marked population compared to others age-groups. These nerve cells are both small and large in size and are distributed in small clusters or singly in the area of ganglia sections. In children, VIP-IR in ganglionic neurons decreases. In adult stellate ganglia, VIP-immunoreactive postganglionic neurons rarely occur. In ganglia of an individual human only varicosities of VIP-positive nerve fibers were observed. These results provide the age-dependent reduction of VIP-like immunoreactivity in human stellate ganglia neurons and suggest the different role of this peptide in the function of sympathetic ganglia neurons with age.

Adolescent↗