Origin of sympathetic and sensory innervation of the elbow joint in the rat: a retrograde axonal tracing study with wheat germ agglutinin conjugated horseradish peroxidase.

After injection of wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) into the elbow joint of adult rats, labeled neurons were found in the stellate and the T2-T4 ganglia of the ipsilateral sympathetic trunk, and also in dorsal root ganglia at the C4-T4 levels. Most labeled sympathetic cells, 90% or more, were located in the stellate ganglion. The sensory innervation to the joint originated mainly from the dorsal root ganglia at the levels of C7-T1.

A developmentally regulated isoform of 150,000 molecular weight neurofilament protein specifically expressed in autonomic and small sensory neurons.

Neurofilament heterogeneity has been demonstrated using a monoclonal antibody (CH1) specific for the 150,000 molecular weight neurofilament subunit. In the peripheral nervous system of adult rats CH1 stained selectively sympathetic and parasympathetic neurons and a subpopulation of small neurons in the sensory dorsal root ganglia. Somatic motor neurons and large neurons in dorsal root ganglia were completely unreactive. In contrast, the anti-neurofilament antibody iC8, directed against the 150,000 molecular weight subunit, labelled all peripheral nervous system neurons. The immunostaining pattern with both antibodies was unchanged by phosphatase treatment. These data indicate that two antigenically distinct variants of the 150,000 molecular weight neurofilament subunit exist in somatic and autonomic neurons of adult animals. In addition, the phosphatase treatment suggests that the antigen recognized by CH1 is not masked by phosphorylation. In contrast, all neurons were labelled by this antibody in the peripheral nervous system of newborn rats. It is suggested that CH1 identifies a fetal 150,000 molecular weight neurofilament polypeptide isoform whose expression is prevented by the growth of somatic neurons and is selectively maintained in autonomic and small sensory neurons.

The sympathetic and sensory components of the caudal lumbar sympathetic trunk in the cat.

The cell bodies of the lumbar sensory and sympathetic pre- and postganglionic neurons that project in the caudal lumbar sympathetic trunk of the cat have been labeled retrogradely with horseradish peroxidase applied to the central end of their cut axons. The application was made just proximal to the segmental ganglion that sends its gray rami to the L7 spinal nerve, and so identified the sympathetic outflow concerned primarily with the vasculature of the hindlimb and tail. The numbers, segmental distribution, location, and size of the labeled somata have been determined quantitatively. Labeled cell bodies were found ipsilaterally, but the segmental distributions of the different cell types were not matched. Afferent cell bodies lay in dorsal root ganglia L1-L5 (maximum L4), preganglionic cell bodies in spinal segments T10-L5 (maximum L2/3), and postganglionic cell bodies in ganglia L2-L5 (maximum L5). Both numbers and dimensions of labeled dorsal root ganglion cells were variable between experiments (maximum about 1,000); the majority were small relative to the entire population of sensory neurons. Labeled preganglionic cell bodies were located right across the intermediate region of the spinal cord, extending from the lateral part of the dorsolateral funiculus to the central canal. The highest density of labeled neurons lay at the border between the white and gray matter (corresponding to the intermediolateral cell column) with smaller proportions medially in L1-L2, and laterally in caudal L4-L5. Medial preganglionic neurons were generally larger than those lying in lateral positions. From the data, it is estimated that about 650 afferent, about 4,500 preganglionic, and some 2,500 postganglionic neurons project in each lumbar sympathetic trunk distal to the ganglion L5 in the cat.

Sensory and autonomic innervation of non-hairy and hairy human skin. An immunohistochemical study.

Non-hairy and hairy human skin were investigated with the use of the indirect immunohistochemical technique employing antisera to different neuronal and non-neuronal structural proteins and neurotransmitter candidates. Fibers immunoreactive to antisera against neurofilaments, neuron-specific enolase, myelin basic protein, protein S-100, substance P, neurokinin A, neuropeptide Y, tyrosine hydroxylase and vasoactive intestinal polypeptide hydroxylase and vasoactive intestinal polypeptide (VIP) were detected in the skin with specific distributional patterns. Neurofilament-, neuron-specific enolase-, myelin basic protein-, protein S-100, neuropeptide Y-, tyrosine hydroxylase- and vasoactive intestinal polypeptide (VIP)-like immunoreactivities were found in or in association with sensory nerves; moreover, neuron-specific enolase-, myelin basic protein-, protein S-100, neuropeptide Y-, tyrosine hydroxylase- and vasoactive intestinal polypeptide (VIP)-like immunoreactivities occurred in or in association with autonomic nerves. It was concluded that antiserum against neurofilaments labels sensory nerve fibers exclusively, whereas neuron-specific enolase-, myelin basic protein- and protein S-100-like immunoreactivities are found in or in association with both sensory and autonomic nerves. Substance P- and neurokinin A-like immunoreactivities were observed only in sensory nerve fibers, and neuropeptide Y- and tyrosine hydroxylase-like immunoreactivities occurred only in autonomic nerve fibers, whereas vasoactive intestinal polypeptide (VIP)-like immunoreactivities was seen predominantly in autonomic nerves, but also in some sensory nerve fibers.

[GABAergic neurons in the mammalian intestine].

Most of the criteria for identification of a neurotransmitter were satisfied for gamma-aminobutyric acid (GABA) in the mammalian intestine. GABA and its synthesizing enzyme, glutamic acid decarboxylase, and the neurons which specifically accumulate GABA were demonstrated to localize in Auerbach's plexus of the intestine. GABA was demonstrated to be released from nerve terminals of the intestine when the nerve fibers were stimulated. The application of GABA depolarized the neurons within Auerbach's plexus. The actions of GABA were mimicked by muscimol on the GABAA receptor and by baclofen on the GABAB receptor. The GABAA antagonist is bicuculline, but no antagonist to GABAB is known at present. Thus, GABAergic neurons may be present in the enteric nervous system of the intestine. GABA and bicuculline changed the propulsive activity and the spontaneous motility of circular muscle, and the neuronal interactions, substance Pergic-GABAergic-postganglionic cholinergic neurons were found in the enteric nervous system, thereby suggesting that GABAergic neurons play a key role in the control of peristalsis.