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PubMed1976

Histochemical light microscopic study of catecholamine containing paraganglia in the human pelvis.

Histological and histochemical techniques have been employed to determine the structure and autonomic innervation of paraganglia located in the human pelvis. In foetal and early postnatal tissues, paraganglia formed rounded cellular masses which were frequently in company with the autonomic nerves and ganglia of the urinary bladder and other pelvic viscera. The constituent cells contained only small amounts of cholinesterase and were unrelated to enzyme positive autonomic nerves; acetylcholinesterase containing nerves were occasionally observed in the capsule and the fibrous septa of the pelvic paraganglia. In early postnatal specimens, pelvic paraganglia frequently contained single or multiple "pacinian-like" corpuscles, each possessing a central region which was rich in both acetyl and pseudocholinesterase. These structures were rarely observed within autonomic ganglia and were absent 4 1/2 years post partum. By means of a histochemical technique, pelvic paraganglia were found to contain catecholamine which was attributed to the presence of relatively large quantities of noradrenaline. These observations have been discussed with particular reference to the results of other studies on the autonomic innervation of paraganglia.

Child, Preschool↗
PubMed1979

Ultrastructure and possible function of an atrial paraganglion not directly related to atrial ganglion in the albino mouse.

The ultrastructure of a paraganglion found in right atrium of albino mouse close to the superior cava vein is described. A capillary, which occupied the central part of the paraganglion, was surrounded by three chromaffin cells. Two other chromaffin cells were also present, but neither nerve fibers nor nerve endings were seen. The possible physiological role of paraganglia is discussed.

Albinism↗
PubMed1978

The distribution and endocrine nature of the abdominal paraganglia of adult man.

The paraganglia of adult man were studied using the formaldehyde-induced fluorescence (FIF) method for histochemical characterization of biogenic monoamines. Microspectrofluorimetry was used to record the emission spectra and fluorescence intensities of the paraganglionic cells. The study of samples from six patients showed that well vascularized paraganglia were widely distributed throughout the retroperitoneal spaces. The paraganglia exhibited strong FIF with the spectral characteristics of monamines. Treatment with HC1 caused an increase in the fluorescence intensity of the paraganglia and a simultaneous shift of the emission maximum from 480--495 nm. This change suggests the presence of high concentrations of tryptophyl-containing peptides and is not due to monoamines. The possibility of a dual endocrine function for the paraganglia is discussed.

Abdomen↗
PubMed1978

Paraganglia of the bladder.

Normal paraganglia containing high amounts of catecholamines are a constant feature of the wall of the bladder in elderly men. The paraganglia in this location might give rise to pheochromocytomas. The importance of the local endocrine effects in the regulation of the muscular tone in the bladder is discussed.

Chromaffin System↗
PubMed1975

Ganglion cells and paraganglionic cells in the developing superior cervical ganglion of normal and p-chlorophenylalanine treated rats.

Ganglion cells and paraganglionic (PG) cells in the developing rat superior cervical ganglion were studied following postnatal treatment with p-chlorophenylalanine (pCPA) for 5 to 8 days. Litter mates, injected with saline solution, served as controls. Ganglion cells of control animals were differentiated ultrastructurally according to L. Eränkö (1972a) into late sympathicoblasts and young sympathetic nerve cells. In both maturation stages treatment with pCPA caused marked swelling of mitochondria, concomitant with minor changes of other cell organelles. Parallel to the ultrastructural alterations, fluorescence microscopy and cytophotometry revealed a slight diminution of diffuse fluorescence intensity in sympathetic neurons as the expression of a mainly extragranular amine depletion. In distinction from ganglion blocking agents the alterations are regarded as a general toxic effect of pCPA upon maturing sympathetic neurons, which secondarily influences catecholamine storage sites. Following treatment with pCPA, in PG-cells an alteration of mitochondria was scarcely to recognize. Specific granules were distinctly decreased in number, in some cases to an almost complete degree. Concordant to ultrastructural observations a marked diminution of fluorescence intensity was demonstrable in SIF-cells. In addition in these elements the fluorescence spectrum shifted towards the green field. Fluorescence cytophotometric evaluations confirmed the optical impression. Provided, that PG-cells, demonstrated with electron microscopy, are identical with SIF-cells in fluorescence microscopy, the results are discussed on the basis of a specific decrease of primary catecholamines due to an enzyme inhibition involved in catecholamine synthesis.

Animals↗
PubMed1975

Effects of guanethidine on paraganglionic cells in the superior cervical ganglion of the rat.

Paraganglionic cells in the rat superior cervical ganglion were investigated by fluorescence and electron microscopy following treatment with guanethidine for 5-30 days. Control animals received saline and guanidine. Fluorescence cytophotometric measurements revealed a general decrease in the catecholamine content of paraganglionic cells in guanethidine-treated animals. However a few cell clusters showed focal increases. Similarly by electron microscopy there was a general decrease of cell clusters showing increases. -- guanethidine -- as well as guanidine--treated animals showed non-specific cytological alterations such as mitochondrial swelling and increase of cytoplasmic glycogen. However no changes of catecholamine contents and of dense core vesicles were noted in control animals. These results confirm the conception that in rat paraganglionic cells the dense core vesicles are the main storage site of catecholamines. The marked difference in the response of some cell culsters to the experimental treatment can be considered as evidence of functional heterogeneity of this cell population in the rat superior cervical ganglion.

Animals↗
PubMed1975

[5-Methoxy-N-acetyltryptamine (melatonin) in enterochromaffin cells].

As evidenced from the action of acetone extracts of the mucous layer of the human appendix, these extracts contain a substance capable of bleaching the frog's skin. Model experiments with 0.1% adrenaline, 0.2% noradrenaline, 2.5% hydrocortisone and solutions of various concentrations of synthesized melatonin permitted to identify the above substance as melatonin. The bleaching aciton dependence on the number of enterochromaffin cells (Ec-cells) in the mucous layer of the appendix, and the presence of serotonin in Ec-cells reveal a connection between melatonin and Ec-cells. An average content of 5-methoxy-N-acetyltryptamine in the human appendix amounts to 0.004 mg per 100 Ec-cells. It is suggested that the epiphysis and enterochromaffin cells compose a common functional neuroendocrine system playing a definite role in maintaining the homeostasis of the organism.

Animals↗
PubMed1975

Neurohumoral mechanisms in hypertension.

Neurohumoral mechanisms operating via the catecholamines are discussed in their relationship to such hypertensive diseases as pheochromocytoma and labile and established essential hypertension. 2. In pheochromocytoma, diagnosis depends almost entirely on identification of increased amounts of catecholamine metabolites in the urine. Because of the danger, manipulative or invasive procedures both for diagnosis and during surgery should be kept at a minimum. 3. In established essential hypertension, reactivity to norepinephrine and plasma norepinephrine are increased, whereas norepinephrine uptake and apparent secretion rate are decreased. 4. In labile essential hypertension, reactivity to epinephrine and probably plasma epinephrine are increased and uptake of epinephrine decreased. 5. Labile hypertension with all its characteristics may or may not coexist with established essential hypertension with all its features. 6. The sympathetic nervous system is also involved in other types of hypertensive disease. Many patients with renovascular hypertension as well as with primary and secondary hyperaldosteronism also have essential hypertension. Angiotensin II affects the sympathetic nervous system and the juxtaglomerular apparatus appears to be beta adrenergic receptor activated, at least in part.

Acetylcholine↗
PubMed1975

[Peripheral secretion and inactivation of catecholamines (adrenaline, noradrenaline, dopamine)].

In spite of the biochemical relationship between catecholamines (E,NE,DA), the unity of the adrenergic system is only apparent; catecholamines are present in numerous pools, which exhibit different anatomical and cellular localizations, secretory patterns, control of release, physiological functions, inactivation schemes and metabolic behaviour. The main sources of catecholamines in the periphery are the orthosympathetic nervous system, which is permanently active in maintaining homoeostasy, and the adrenal medulla, an essential element in the struggle against stress. In addition to these large pools, catecholamines are found also in extra adrenal chromaffin tissue and in sympathetic ganglions; the latter represents a potential store of amines, whilst ganglionic dopamine-rich interneurones are important links in the regulation of orthosympathetic activity. Rather than by a topographic distinction, it seems more satisfactory to classify the catecholamines spread in adrenergic fields into a small number of pools possessing their own physiological functions and inactivation patterns. Two main pools of catecholamines in the periphery may be described: The functional pool, represented by those catecholamines already released, or able to be released; in this pool are found plasma and adrenal medullary catecholamines and NE from sympathetic nerve endings. The tissue pool, consisting of the synthesis and storage compartments, which are poorly penetrated by plasma pool with respect to their high possibilities for synthesis and storage. Catecholamines from cellular bodies and axons of sympathetic neurons and a part of the adrenal medullary amines may be related to it. Two other pools of catecholamines have to be reported: a potential extrachromaffin pool, which is apparently negligible in the physiological state, but able to exhibit its synthetic and secretory capacities in particularly critical situations; an intraganglionic dopamine pool, which plays a modulator role in ganglionic synaptic transmission; its mode of secretion and inactivation are not necessarily the same as those of the above pools. To such a physiological diversity, specific regulatory processes, correspond the aim of which is, to stop physiological activity of released catecholamines, by means of physical and chemical inactivating mechanisms; to limit the amount of released product by local control of the neuromediator outflow; to minimize losses of active compound by neuronal and cellular uptake and perhaps by sulfoconjugation; to destroy the excess of synthesized or reabsorbed amines when tissue or neuronal concentration becomes too high (tissue metabolism).

Acetylcholine↗
PubMed1976

The paraganglia, a persisting endocrine system in man.

The paraganglia have been traced in surgical samples of para-aortic and pelvic retroperitoneal tissues using the formal-dehyde-induced fluorescence method for catecholamines. Clusters of catecholamine-storing cells were found in all (12) patients studied. Microspectrofluorometric recordings showed high amounts of catecholamine in the well-vascularized cell groups. A large proportion of the paraganglia, which are most prominent during the fetal period, also persist during postnatal life.

Adult↗
PubMed1975

[On the possibility to demonstrate the presence of catecholamines in enterochromaffin cells: critical review (author's transl)].

Various data contributing to support, after Lillie et al., the presence of catecholamines instead of (or in addition to) 5-hydroxytryptamine in the enterochromaffin cells, are submitted to analytical criticism by the Author. Topics of the discussion are mainly the behaviour of the diazo-reaction (in acid medium), the fluorescence induced by formaldehyde, and various reactions carried out either directly or following a chemical block. The Author demonstrates that 5-HT is present in the enterochromaffin cells and that it is impossible, at present time, to prove the presence of catecholamines in these cells on the basis of histochemical data. The Author debates also how biochemical or pharmacological tests may supply the lacking of histochemical proofs in demonstrating the presence of catecholamines; it is possible by applying these procedures to study situations like those postulated by Lillie et al., extending a comparative research also to other elements of the enterochromaffin cell system after ERSPAMER; the examples here reported however do not agree perfectly in some of the cases with these views.

Animals↗
PubMed1978

[Endocrine apparatus of human gastric mucosa].

Endocrine cells of the gastric fundal and pyloric mucosa in patients suffering from gastric and duodenal ulcers with different gastric juice acidity, were studied. At hyperacid ulcers, the number of argyrhilic endocrine cells of gastric fundus was increased to 218 +/- 21.1 as compared with the normal acidity 164 +/- 14.8, while it was decreased to 97 +/- 15.1 as compared with hypoacidity. Argentaffinic cells were found in patients with hypo- and unacid gastric juice only. The electron microscopy revealed six types of endocrine cells (A-like, ECL, G, D, D1, EC). The ultrastructural changes of A-like, ECL, and G cells in patients with hyperacid gastric juice indicated their high functional activity. A balance seems to exist between activating and inhibiting systems of the endocrine apparatus of gastric mucosa which accounts for the hyperacidity of the gastric juice.

Cell Count↗
PubMed1976

Melatonin and enterochromaffine cells.

As a result of investigations active biosynthesis of melatonin was found in enterochromaffin cells of gastrointestinal tract. It is suggested to unify epiphysis and enterochromaffine cells into a united functionally active neuroendocrine system, which plays an important role in the control of rhythms of biological processes in the body.

Animals↗