-
Microscopy Research and Technique Sep 1998The present paper deals with the origin and neurochemical characteristics of autonomic postganglionic and sensory nerve fibres supplying the mammalian vas deferens. The... (Review)
Review
The present paper deals with the origin and neurochemical characteristics of autonomic postganglionic and sensory nerve fibres supplying the mammalian vas deferens. The vas deferens is innervated by postganglionic nerve fibres originating primarily from neurons in pelvic ganglia and, to a lesser extent, from neurons in the inferior mesenteric ganglion and sympathetic chain ganglia as well as by sensory nerve fibres arising from dorsal root ganglia. Three major populations of nerve terminals innervating the organ can be distinguished: (1) noradrenergic fibres; (2) cholinergic fibres containing vasoactive intestinal polypeptide, neuropeptide Y, nitric oxide synthase, and (in the pig) somatostatin, supplying particularly the lamina propria; and (3) non-noradrenergic, presumably sensory fibres, containing calcitonin gene-related peptide and/or substance P. The population of noradrenergic nerves is the most common. In the pig, it can be divided into three subpopulations: a somatostatin-containing, a Leu-enkephalin-containing and a subpopulation immunonegative to these peptides, in descending order of magnitude. In the rat, guinea-pig, and man, NPY seems to be the most common peptide occurring in the noradrenergic axons. In the pig, coexistence patterns of the substances existing within nerve fibres supplying the vas deferens blood vessels are clearly different from those found in nerve fibres innervating the organ wall. The majority of the noradrenergic fibres associated with blood vessels contain neuropeptide Y only, while non-noradrenergic perivascular nerves contain predominantly vasoactive intestinal polypeptide. The possibility of different sources of origin of the particular nerve fibre subpopulations supplying the mammalian vas deferens and its blood vessels is discussed.
Topics: Afferent Pathways; Animals; Autonomic Fibers, Postganglionic; Humans; Male; Nerve Fibers; Neural Pathways; Neurons, Afferent; Neuropeptides; Vas Deferens
PubMed: 9817548
DOI: 10.1002/(SICI)1097-0029(19980915)42:6<409::AID-JEMT4>3.0.CO;2-H -
Journal of Neural Transmission.... 1990Neuropeptide Y (NPY) is closely associated to stress-reactive structures in the central and peripheral nervous system. In the periphery, the peptide is colocalized with... (Review)
Review
Neuropeptide Y (NPY) is closely associated to stress-reactive structures in the central and peripheral nervous system. In the periphery, the peptide is colocalized with catecholamines in postganglionic sympathetic fibres and the adrenal medulla. In the brain, the paraventricular nucleus of the hypothalamus receives a dense innervation of NPYergic neurons, some of which also contain monoamines. With the use of a specific immunoradiometric assay, we have demonstrated that NPY is released into the peripheral circulation during psychological stress together with catecholamines. The postganglionic origin of the peptide was demonstrated by the activity of the nicotinic antagonist hexamethonium to attenuate the response. Adrenalectomy or insulin-induced hypoglycemia did not alter basal or stimulated NPY plasma levels, showing that the adrenal is not a major source of circulating NPY in the rat. Although NPY and noradrenaline are frequently released in parallel in various experimental conditions, a clear dissociation can be found in several cases, such as cold stress or the response to phentolamine, where no change can be seen in plasma NPY despite a large activation of noradrenergic terminals. Furthermore, the neuropeptide may play a role in stress-induced pathological states such as hypertension, since its release is greater in animals previously submitted to chronic stress and high-sodium diet. On the other hand, its role in the central nervous system control mechanisms of the stress response is far from being clear, but to understand the interaction of NPY we need a better knowledge of the role of noradrenergic neurons in the central control of the adrenocortical axis or sympathetic nervous system activity.
Topics: Adrenal Glands; Animals; Autonomic Fibers, Postganglionic; Brain; Humans; Neuropeptide Y; Stress, Psychological
PubMed: 2193112
DOI: 10.1007/978-3-7091-9050-0_8 -
Neuroscience Jul 1996
Review
Topics: Animals; Autonomic Fibers, Postganglionic; Autonomic Nervous System; Axons; Humans; Neuroeffector Junction; Neurotransmitter Agents; Synaptic Transmission
PubMed: 8783226
DOI: 10.1016/0306-4522(96)00031-0 -
Journal of Anatomy Oct 1990The pre- and postganglionic sympathetic innervation of the guinea-pig adrenal medulla was investigated using the retrograde neuronal tracers Fast Blue and WGA-HRP....
The pre- and postganglionic sympathetic innervation of the guinea-pig adrenal medulla was investigated using the retrograde neuronal tracers Fast Blue and WGA-HRP. Labelled preganglionic cell bodies were located in the intermediolateral horn of spinal segments T3-L2, the majority (73.9%) were found between T6-T12 representing 70.2% of the total number of labelled cells; the segment T10 contained the largest number of labelled neurons. Labelled postganglionic cell bodies were found in the paravertebral ganglia between vertebral levels T3-T12 (representing 22.6% of the total labelled neurons), the maximum number was found at T10. In addition, labelled neurons were found in the suprarenal ganglion (representing 7.2%). No labelled cells were found in the coeliac ganglia. The labelled neurons were found ipsilateral to the site of injection into the left adrenal gland. It is concluded that the guinea-pig adrenal gland receives both a pre- and a significant postganglionic sympathetic innervation. The destination of these nerve fibres within the adrenal gland has yet to be determined.
Topics: Adrenal Glands; Amidines; Animals; Autonomic Fibers, Postganglionic; Autonomic Fibers, Preganglionic; Female; Ganglia, Sympathetic; Guinea Pigs; Horseradish Peroxidase; Male; Spinal Cord; Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; Wheat Germ Agglutinins
PubMed: 1703141
DOI: No ID Found -
Journal of the Autonomic Nervous System Sep 1982Conduction velocities of unmyelinated fibers and proportions of postganglionic fibers which can be activated from the lumbar sympathetic trunk were determined for the...
Conduction velocities of unmyelinated fibers and proportions of postganglionic fibers which can be activated from the lumbar sympathetic trunk were determined for the superficial peroneal nerve of the cat's hindlimb. The nerve was either left intact (4 control experiments) or cut and ligated peripherally 6-245 days before the experiments so that neuromata developed (15 experiments). Additionally, 3 control experiments were performed on the sural nerve. Our findings are that about 20-30% of all unmyelinated fibers in intact skin nerves are postganglionic sympathetic fibers. This percentage of postganglionic axons, which can be activated from the preganglionic side, decreases to 0-7% 100 days or more after the nerve section. In intact skin nerves the conduction velocity of the afferent unmyelinated fibers is greater (mean +/- 1 S.D.: 0.88 +/- 0.17 m/s) than that of postganglionic axons (0.69 +/- 0.14 m/s). The conduction velocities in both types of axons decrease by 25-30% in nerves with peripheral neuroma. This occurs largely during the first 15 days following the nerve section described.
Topics: Adrenergic Fibers; Afferent Pathways; Animals; Autonomic Fibers, Postganglionic; Axons; Cats; Electric Stimulation; Nerve Fibers; Neural Conduction; Neuroma; Peroneal Nerve; Skin; Sural Nerve
PubMed: 7175084
DOI: 10.1016/0165-1838(82)90049-2 -
The American Journal of Physiology Jan 1991Previous reports indicate that alpha-adrenergic agonists modulate vagal control of heart rate. In the rat, phenylephrine inhibition of vagal-stimulated bradycardia may... (Comparative Study)
Comparative Study
Previous reports indicate that alpha-adrenergic agonists modulate vagal control of heart rate. In the rat, phenylephrine inhibition of vagal-stimulated bradycardia may be occurring at any of a number of sites along the cardiac parasympathetic pathway. The purpose of the present experiments was to localize the pre- or postganglionic sites of phenylephrine modulation of parasympathetic-mediated bradycardia in the rat. Sprague-Dawley rats were anesthetized and instrumented with arterial and venous catheters and electrocardiographic leads. The cervical vagi were sectioned, and propranolol was administered. The right cervical vagus nerve was electrically stimulated to activate preganglionic parasympathetic nerves. Carbachol was injected to activate nicotinic receptors on postganglionic parasympathetic nerves (i.e., intracardiac ganglion cells). Methacholine was injected to activate muscarinic receptors at the sinoatrial node. The heart rate responses to these three interventions were recorded before, during, and after phenylephrine infusion. Phenylephrine significantly attenuated the bradycardia produced by vagal nerve stimulation. In contrast, phenylephrine facilitated the bradycardia elicited by carbachol injection. Since carbachol has both muscarinic and nicotinic effects, the results were compared with those obtained from methacholine, a pure muscarinic agonist. Phenylephrine had no effect on methacholine-induced bradycardia, suggesting that the modulation of the carbachol response was through carbachol's nicotinic effects. Yohimbine, the alpha 2-receptor antagonist, eliminated phenylephrine-mediated facilitation of the carbachol response. These data indicate that phenylephrine has contrasting effects on pre- and postganglionic cardiac parasympathetic nerves in rats: inhibition at preganglionic sites (vagal stimulation results) and facilitation at the level of the ganglion cells (carbachol experiments).
Topics: Animals; Autonomic Fibers, Postganglionic; Autonomic Fibers, Preganglionic; Carbachol; Heart Rate; Male; Parasympathetic Nervous System; Phenylephrine; Propranolol; Rats; Rats, Inbred Strains; Vagus Nerve; Yohimbine
PubMed: 1992788
DOI: 10.1152/ajpheart.1991.260.1.H118 -
Journal of the Autonomic Nervous System Apr 1981The organization of pre- and postganglionic neurons supplying blood vessels of the skin (vasoconstrictor neurons) and of the skeletal muscle (vasoconstrictor neurons),...
The organization of pre- and postganglionic neurons supplying blood vessels of the skin (vasoconstrictor neurons) and of the skeletal muscle (vasoconstrictor neurons), sweat glands (sudomotor neurons) and erector pilimuscles (pilomotor neurons) of the cat's hind limb and tail is discussed. Each sympathetic subsystem has its own, though as yet unknown, central organization which is reflected in the reaction patterns typically seen. The conduction velocities of the pre- and postganglionic axons of each subsystem have their unique distributions. Postganglionic vasoconstrictor neurons supplying skeletal muscle and skin are influenced via cholinergic muscarinic and non-cholinergic synaptic mechanisms from thin, probably unmyelinated, preganglionic axons; postganglionic sudomotor and pilomotor neurons most likely do not receive this synaptic input. A high proportion of preganglionic neurons projecting with their axons onto postganglionic neurons which supply skin and skeletal muscle are silent and do not exhibit reflex activity. Some of these neurons synapse with postganglionic pilomotor, vasodilatator and sudomotor neurons; part of them may also synapse with vasoconstrictor neurons. However, the high proportion of preganglionic neurons without reflex and resting activity which cannot be classified on the basis of functional properties presents a considerable problem in the analysis of the central organization of the sympathetic nervous system. It is concluded that the 4 types of pre- and postganglionic neurons mentioned constitute 4 largely separate channels which transmit information from the spinal cord to the respective target organs.
Topics: Afferent Pathways; Animals; Autonomic Fibers, Postganglionic; Autonomic Fibers, Preganglionic; Autonomic Nervous System; Cats; Hindlimb; Muscle, Smooth, Vascular; Muscles; Neurons; Piloerection; Sensory Receptor Cells; Skin; Spinal Cord; Sweat Glands; Sympathetic Nervous System; Synaptic Transmission; Vasoconstriction
PubMed: 6268686
DOI: 10.1016/0165-1838(81)90062-x -
Acta Physiologica Scandinavica Sep 1972
Topics: Acetylcholine; Animals; Autonomic Fibers, Postganglionic; Dogs; Electric Stimulation; Facial Nerve; Maxillary Artery; Neurosecretion; Parasympathetic Nervous System; Parotid Gland
PubMed: 4638316
DOI: 10.1111/j.1748-1716.1972.tb00230.x -
Journal of Neuropathology and... Nov 2012Skin biopsy has gained widespread use for the diagnosis of somatic small-fiber neuropathy, but it also provides information on sympathetic fiber morphology. We aimed to...
Skin biopsy has gained widespread use for the diagnosis of somatic small-fiber neuropathy, but it also provides information on sympathetic fiber morphology. We aimed to ascertain the diagnostic accuracy of skin biopsy in disclosing sympathetic nerve abnormalities in patients with autonomic neuropathy. Peripheral nerve fiber autonomic involvement was confirmed by routine autonomic laboratory test abnormalities. Punch skin biopsies were taken from the thigh and lower leg of 28 patients with various types of autonomic neuropathy for quantitative evaluation of skin autonomic innervation. Results were compared with scores obtained from 32 age-matched healthy controls and 25 patients with somatic neuropathy. The autonomic cutoff score was calculated using the receiver operating characteristic curve analysis. Skin biopsy disclosed a significant autonomic innervation decrease in autonomic neuropathy patients versus controls and somatic neuropathy patients. Autonomic innervation density was abnormal in 96% of patients in the lower leg and in 79% of patients in the thigh. The abnormal findings disclosed by routine autonomic tests ranged from 48% to 82%. These data indicate the high sensitivity and specificity of skin biopsy in detecting sympathetic abnormalities; this method should be useful for the diagnosis of autonomic neuropathy, together with currently available routine autonomic testing.
Topics: Adult; Aged; Autonomic Nervous System Diseases; Biopsy; Epidermis; Female; Humans; Male; Middle Aged; Nerve Fibers, Unmyelinated; Sympathetic Fibers, Postganglionic
PubMed: 23037327
DOI: 10.1097/NEN.0b013e3182729fdc -
Proceedings of the Royal Society of... Apr 1971
Topics: Animals; Anura; Autonomic Fibers, Postganglionic; Axons; Cytoplasmic Granules; Ganglia, Autonomic; Heart Septum; Microscopy, Electron; Synapses
PubMed: 4396517
DOI: 10.1098/rspb.1971.0044