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Biomedical subjects

A Hervonen

Publications and source records attributed to A Hervonen.

At least 109 records · Page 6Linked to original sources
PubMed1980

Electron-microscopic localization of enkephalin-like imnmunoreactivity in axon terminals of human sympathetic ganglia.

The peroxidase-antiperoxidase method was applied to demonstrate enkephalin-like immunoreactivity in the human sympathetic ganglia. A network of immunoreactive fibres was found in light microscopy between the nonreactive neurons. Electron microscopy showed immunostaining to be restricted to axonal profiles containing both large and small vesicles. The strongest reaction was associated with large vesicles.

Adult↗
PubMed1980

The effect of ageing on the histochemically demonstrable catecholamines in the hypogastric (main pelvic) ganglion of the rat.

The effect of ageing on adrenergic neurons was studied in the hypogastric ganglion of the male rat using the formaldehyde-induced fluorescence method. With age, two changes were obvious. Firstly, the fluorescence intensity of the neurons decreased throughout postnatal life and the number of completely non-fluorescent adrenergic neurons increased. Secondly, the amount of non-specific fluorescence due to lipofuscin pigment increased. The pigment fluorescence was also found around the neurons in satellite cells.

Aging↗
PubMed1980

Microspectrofluorimetric estimation of the formaldehyde-induced fluorescence of the developing main pelvic ganglion of the rat.

The formaldehyde-induced fluorescence (FIF) of the cytoplasm of individual developing neurons of the main pelvic ganglion was recorded microspectrofluorimetrically in order to follow changes in catecholamine (noradrenaline) content during development. For each ganglion, the fluorescence intensity profile was estimated and shown graphically as columns expressing percentage distribution of relative intensities in different intensity classes. During development, the number of weakly fluorescent neurons increases. Treatment with testosterone shifts the profile towards higher intensities in four- and six-week-old animals. Testosterone affected the main pelvic ganglion but not the superior cervical ganglion. The intensity of the cytoplasmic FIF, which correlates with the catecholamine (noradrenaline) content of the object tissue, showed a tendency to decrease during development. This change was not obvious vy visual observation because of the increase in cell size and the toal bulk of the ganglion. Other possible factors affecting visual observation are discussed.

Animals↗
PubMed1980

Ultrastructure of neurosecretosomes sedimented in the nuclear fraction from the posterior pituitary of the rat.

Subcellular fractions of the posterior pituitary of the rat were isolated by differential and density gradient centrifugation, and microsamples prepared for electron miscroscopy by KMnO4 or glutaraldehyde-OsO4 fixation. The nuclear fraction, P1 (1000 g x 7 min), was the main neurosecretosome (NSS) fraction and contained nuclei and mitochondria in addition to NSS (60%). The crude mitochondrial fraction, P2 (10,000 g x 20 min), contained free mitochondria (70%), NSS, unidentified membrane particles, fat droplets derived from pituicytes, neurosecretory granules (NSG) and synaptosomes, identified by the presence of synaptic membrane thickenings. Fraction P3 (32,900 g x 20 min) contained mainly free NSG, while fraction P4 (118,000 g x 30 min) had a high microsome content.

Animals↗
PubMed1980

Autonomic innervation of the human prostate.

The autonomic innervation of the human prostate has been studied using both light and fluorescence microscopic techniques. A dense network of both adrenergic and acetylcholinesterase-positive nerves innervates the smooth muscle around the ducts and acini of the prostate. No direct innervation of the acinar epithelium can be observed. The role of the innervation in both normal and pathologic states is discussed.

Adrenergic Fibers↗
PubMed1980

Effect of aging on SIF cells of the rat.

The effect of aging on the SIF cells was studied with the formaldehyde-induced fluorescence (FIF) method and electron microscopy (EM). For EM the specimens were fixed with glutaraldehyde-OsO4 and KMnO4. The emission spectra were recorded microspectrofluorimetrically. Under fluorescence microscopy in newborn and young adult rats, only one type of SIF cell emitting greenish-yellow FIF could be found, whereas in aged rats another type of SIF cell emitting yellowish-brown, granular FIF was also found. The emission spectra of the greenish-yellow FIF of the newborn and young adults and the aged rats differed from that recorded from the yellowish-brown granular SIF cells. According to the size of the dense-cored vesicles, two kinds of SGC cell could be distinguished in the hypogastric ganglion of the newborn and the young adult rats after glutaraldehyde fixation. The first type contained 50- to 150-nm vesicles, and the second type contained 50- to 250-nm vesicles. In aged rats a third type of SGC cell containing elongated 50 X 250 nm dense-cored vesicles was found. After KMnO4 fixation the classification was the same as after glutaraldehyde in newborn and young adult animals. In aged rats three types of SGC cell could be distinguished, according to the size, shape, and core of the storage granules; the first with 100- to 300-nm empty vesicles, the second with 100- to 300-nm vesicles with small cores, and the third with 100- to 500-nm irregular vesicles filled with electron-opaque material with a denser core.

Aging↗
PubMed1980

Ultrastructure and histochemistry of human SIF cells and paraganglia.

The FIF method and electron microscopy were used to study SIF cells in the human sympathetic ganglia. In serial sections SIF cells in one ganglion often numbered less than 30, although they were found in every ganglion examined. Microspectrofluorimetry demonstrated the high catecholamine content in SIF cells. Electron microscopically these cells appeared as small granule-containing cells that receive a rich cholinergic type innervation. The diameter of the storage granules was 300 to 400 nm. In addition the SIF cells had close connections with each other. The SIF cells, situated solitary or as small clusters, were surrounded by satellite cells. Frequently the SIF cells located close to blood vessels.

Catecholamines↗
PubMed1979

Vacuolated neurons in the hypogastric ganglion of the rat.

The vacuolated neurons (VN) of the main hypogastric ganglion of the male rat were studied using the formaldehyde-induced fluorescence (FIF) method for the histochemical demonstration of catecholamines. Microspectrofluorimetry was performed to identify the fluorophores and to quantify the FIF. The thiocholine method (Koelle-Gomori) was used to demonstrate acetylcholinesterase activity. The fine structure of the VN was studied using glutaraldehyde/OsO4 fixation. (1) In the untreated adult male rat VN represent only a small population of the total number of hypogastric neurons (0.8--1.2%). The vacuoles are similar to those of the VN from the corresponding female ganglion. (2) The VN are considered to be adrenergic due to the nature of their fluorophore, indicating a primary catecholamine. (3) The first VN appear in the hypogastric ganglia at the age of 7 weeks. After testosterone administration to young rats, VN are found at the age of 4 weeks. (4) The basic fine structure of the VN is similar to that of other ordinary neurons of the hypogastric ganglia. (5) The content of the vacuoles could not be identified. (6) Indications of degeneration were not observed in the VN. (7) The VN are interpreted as being a functional stage of the "short" adrenergic neurons, which are under the control of steroid hormones. (8) Fifteen months after castration, no VN could be found in the hypogastric ganglia, while their number was normal in the corresponding control animals.

Acetylcholinesterase↗
PubMed1979

Innervation of the ventral prostate of the rat.

The autonomic innervation of the rat ventral prostate was studied in an attempt to evaluate the role of innervation in the normal function of the gland. Specific histochemical methods for both catecholamines (the formaldehyde-induced fluorescence method, FIF) and acetylcholinesterases (the Gomori-Koelle thiocholine method) were used. The neuro-effector contacts were studied by electron microscopy using both 3% glutaraldehyde and 3% potassium permanganate (KMnO4) as fixatives. It was found that the rat ventral prostate receives dual autonomic innervation. Adrenergic fibers, which formed the majority of the nerves, were often seen in close contact with the smooth muscle cells around both the prostatic alveoli and secretory ducts. The non-adrenergic nerve fibers, which were fewer in number, did not form such intimate contacts with the muscle cells. No direct synapses with epithelial cells were detected.

Acetylcholinesterase↗
PubMed1979

The formaldehyde-induced fluorescence of the developing hypogastric (main pelvic) ganglion of the rat. Short adrenergic neurons and the effect of testosterone.

The development of the hypogastric ganglion of normal and testosterone-treated rats was studied using formaldehyde-induced fluorescence (FIF) method. The fluorescence intensities were recorded microspectrofluorimetrically. In normally developing rats cytoplasmic FIF decreases and cell size increases with age. In normally developing rats cytoplasmic FIF decreases and cell size increases with age. In testosterone-treated animals FIF increases during 2--6 weeks compared to the controls. The differences between control and experimental rats were significant. The diameters were significantly longer in treated animals in three and four week old groups. Vacuolated neurons were seen earlier in testosterone-treated rats. No changes in FIF or in cell size were noticed in the superior cervical ganglion. The male sex steroid, testosterone evidently influences the catecholamine turnover and cellular growth during development in the male pelvic ganglion.

Animals↗
PubMed1979

The effect of long-term castration on the histochemically demonstrable catecholamines in the hypogastric ganglion of the rat.

The effect of long-term castration on the hypogastric ganglion of the rat was studied using the formaldehyde-induced fluorescence (FIF) method. After castration the fluorescence intensity was lower and the size of the adrenergic neurons was smaller than in normal or in testosterone-treated castrated rats. The fluorescence profile of the ganglia of castrated rats differed from the profiles of control or testosterone-treated castrated rats. Vacuolated neurons were seen in the hypogastric ganglion of controls but not in the ganglia of castrated animals. After long-term castration the size of the ventral prostate was drastically reduced. The density of adrenergic nerves was similar in castrated, normal and testosterone-treated castrated rats. It is concluded that long-term castration has an effect on adrenergic neurons by decreasing the FIF and by producing other morphological changes. The effect can be reversed by testosterone treatment.

Adrenergic Fibers↗
PubMed1979

Small, intensely fluorescent cells of human sympathetic ganglia.

Human sympathetic ganglia obtained from sympathectomies were studied using the formaldehyde-induced fluorescence (FIF) method and electron microscopy to identify the small, intensely fluorescent (Sif) cells. Microspectrofluorimetry was used to study the intensity of the emitted FIF and the emission spectra. The SIF cells were found in every ganglion studied, but they were very sparce. They occurred alone or in small clusters and were mostly situated close to the blood vessels. The SIF cells contained high amounts of catecholamines, as indicated by microspectrofluorimetry. Electron microscopy revealed granule-containing cells (GC) enveloped by satellite cells; the former cells contained osmiophilic granules 300--400 nm in diameter and synapses of the cholinergic type were frequently found on their surface.

Dopamine↗
PubMed1978

The endocrine nature of the paranganglia of man.

Brightly fluorescent paraganglia were found in the retroperitoneal tissue of adult man. The histofluorescence properties of the paraganglia indicate the presence of tryptophyl peptides, which might be of endocrine importance.

Animals↗