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The formaldehyde-induced fluorescence method was used for light microscopy and fixation in glutaraldehyde and osmium tetroxide for electron microscopy to study the effect of 75 mg/kg 6-hydroxydopamine on the paracervical ganglion of the rat uterus. No changes were observed in the fluorescence intensity of the ganglion. Ultrastructurally the ganglion cells and the synapses remained unchanged. The small, intensely fluorescent (SIF) cells were severely damaged, displaying large vacuoles with an irregular contour as well as smaller, more regular vacuoles studded with ribosomes. The granular vesicles showed a lower density of their central parts suggesting that their catecholamine content had diminished. [ABSTRACT FROM AUTHOR]

The ultrastructure of the rat paracervical (frankenhäuser) ganglion was studied during postnatal development after immersion or perfusion fixation with the glutaraldehyde, followed by postosmification. Three different neuronal cell types were found in the ganglion: (1) Primitive sympathetic nerve cells. They had a 'primitive' structure and contained, in one section, one to two dense cored vesicles (DCV) of 700-1100 Å in diameter. They were not found after the fourth day of postnatal development. (2) Principal neurons grew in size during the whole period of postnatal development. Part of them were already well developed in the ganglia of the newborn rat, and no particular changes in the content of their cytoplasmic organelles occurred thereafter. (3) Small granule-containing (SGC) cells. They usually occurred in small groups, often close to blood capillaries of the fenestrated type and were sometimes devoid of their satellite cell sheath in this region. They became slightly smaller in size as the animal aged. The size of their granulated vesicles (GV) varied mainly between 800-1400 Å in all age groups in most of the cells. In addition, another type of SGC-cell containing larger GV up to 3000 Å in diameter were observed in the ganglia of 32-day old and older rats. Degenerating principal neurons and SGC-cells were encountered, especially in the young animals. Mitotic figures were seen in the SGC-cells up to the 8-day stage. The synapses to the principal neurons were mainly axo-somatic. There were only a few synapses present in the newborn, but their number greatly increased during development. It appeared as if the accumulation of synaptic vesicles preceded or appeared simultaneously with the formation of the pre-and post-synaptic membrane thickenings. Synapses to the SGC-cells were few in all the age groups studied. [ABSTRACT FROM AUTHOR]

Studies the ganglionic blocking activity of Su 3088, a new quaternary ammonium compound. Ability of Su 3088 to suppress nerve transmission through autonomic ganglia; Manifestation by Su 3088 of weaker actions but of longer duration than those of tetraethylammonium chloride; Effect of single initial doses of the drug on the blood pressure of hypertensive patients.

Myelinated fibres in the human sympathetic paravertebral chain were examined histologically and in single teased fibre preparations in various age groups in subjects dying from disorders not affecting primarily the autonomic nervous system. An increase in fibre density predominantly due to an increase in the number of small fibres was found in older subjects. A correlation between internodal length and fibre diameter was found but the internodes of sympathetic myelinated fibres are shorter for any given diameter than those found on fibres of comparable size in the sural nerve. A reduction in internodal lengths with advancing years was demonstrated. These observations are interpreted to show that Wallerian degeneration and segmental demyelination occur with increasing frequency in old age and that regeneration does not keep pace with successive degenerative events. The deterioration in function of the autonomic nervous system with advancing years may be attributed in part to the changes found in myelinated fibres in the paravertebral sympathetic chain. [ABSTRACT FROM AUTHOR]

Eight further cases of neurogenic orthostatic hypotension are described together with a necropsy study on one case. Three cases showed evidence of autonomic dysfunction in isolation, while in five cases this was accompanied by evidence of more diffuse central nervous system degeneration. (Parkinsonism, cerebellar ataxia, dementia, pyramidal signs, bulbar weakness, and muscular wasting were all seen in varying proportions.) The various clinical presentations, investigations, pathology, treatment, and prognosis are discussed. In the experience of the authors, when assessed, an abnormal Valsalva response is invariable, confirming the breakdown of the circulatory reflex. A normal vasopressor response is likewise invariable, eliminating an abnormality of blood vessels themselves, and confirming the lesion as neurogenic. The demonstration of loss of sweating to indirect body heating, which also is usual suggests that the defect is central or on the efferent side of the reflex and a normal pilo-erector response to acetylcholine confirms this as preganglionic. Emphasis is laid on the non-specificity of many accepted physiological tests in this disorder and on the delay in diagnosis consequent upon the variable presentation. [ABSTRACT FROM PUBLISHER]