Reduced leucine-enkephalin--like immunoreactive substance in hamster basal ganglia after long-term ethanol exposure

Golden Syrian hamsters were placed individually in cages with three drinking bottles--one empty, one containing water, and the third containing water and ethanol. Control hamsters received water only. After 1 year the experimental hamsters showed a significantly lower concentration of leucine-enkephalin-like immunoreactive substance in the basal ganglia than the control hamsters. This finding indicates that the action of ethanol involves endogenous peptidyl opiates.

Brain target sites for 1,25-dihydroxyvitamin D3

Autoradiographic studies with 3H-labeled 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] demonstrate, in certain neurons of rat forebrain, hindbrain, and spinal cord, a nuclear retention and concentration of radioactivity, which can be prevented by treatment with 1,25(OH)2D3, but not with 25-hydroxyvitamin D3. These results indicate the presence of brain receptors in addition to pituitary receptors for 1,25(OH)2D3 and suggest a central modulation of calcium homeostasis and other central effects for this hormone. The existence of a brain-pituitary axis for certain 1,25(OH)2D3-mediated endocrine-autonomic effects is postulated.

Iodine-125-labeled triiodothyronine in rat brain: evidence for localization in discrete neural systems

Autoradiograms prepared from adult rat brains demonstrate that nerve cells and neuropil in different brain regions selectively concentrate and retain intravenously administered triiodothyronine, by mechanisms susceptible to saturation with excess triiodothyronine. A neuroregulatory role for thyroid hormones, strongly supported by the observations, may account for their marked effects on behavior and the activity of the autonomic nervous system.

The distal nephron in the chick embryo as a target tissue for 1-alpha-25-dihydroxycholecalciferol

A histological and ultrastructural study as well as an autoradiographic analysis after injection of tritiated 1,25-dihydroxycholecalciferol (1,25-DHCC) were conducted on the distal convoluted tubules of chick embryos. Distal tubules in the embryo were shown to have the same spatial distribution as described for the adult kidney; they presented a convoluted portion located in the vicinity of the central intralobular veins and straight portions irradiating from this region towards the periphery. The epithelium in these tubules was well differentiated; its cells had numerous interdigitating folds in their lateral boundaries which were especially numerous at the basal ends. This device greatly increased the membrane surface available for interchange and was interpreted as an expression of active water and/or mineral transport. Nuclear concentration of radioactivity was found 2 h after injection of tritiated 1,25-DHCC in both the pars convoluta and the pars recta of the distal tubules. This concentration could be blocked by the previous administration of large amounts of nonradioactive 1,25-DHCC. These facts were interpreted as indicating that distal convoluted tubules in the chick embryo are functionally differentiated and contain target cells for 1,25-DHCC.

Immunocytochemical demonstration of nerve growth factor and histofluorescence of catecholaminergic nerves in the salivary glands of diabetic mice

Nerve growth factor (NGF) was localized in the submandibular, sublingual, and parotid salivary glands of male and female diabetic mice and their normal littermates by immunoperoxidase staining using p-phenylenediamine-pyrocatechol as a chromogen for the cytochemical demonstration of peroxidase activity. In the normal male submandibular gland, immunoreactive NGF was localized in the apical regions of granular, intercalated and collecting duct cells, while in the normal female submandibular gland, NGF was present throughout the cytoplasm of granular duct cells. The localization of NGF in the diabetic male and female submandibular glands was similar and resembled that of the normal female. NGF immunoreactivity was also observed in the striated duct cells in the sublingual and parotid glands of all four types of mice. The sympathetic innervation of the submandibular glands of normal and diabetic mice was demonstrated using glyoxylic acid-induced histofluorescence. The pattern of sympathetic innervation and the intensity of catecholamine fluorescence was consistently different in the four types of mice. In the normal male submandibular gland the fluorescence was very intense, particularly in nerves adjacent to the granular ducts. In the normal female submandibular gland, the fluorescence was weak, while in the diabetic male and female the fluorescence was moderate. The correlation between the intensity of the immunocytochemical staining for NGF and the catecholamine fluorescence adjacent to the granular ducts suggests a trophic influence of the NGF-containing granular ducts on their sympathetic innervation.

Anatomical distribution of estrogen target neurons in turtle brain

Autoradiographic studies with [3H]estradiol-17 beta in red-eared turtle (Pseudemys scripta elegans) show concentration and retention of radioactivity in nuclei of neurons in certain regions. Accumulations of estrogen target neurons exist in the periventricular brain with relationships to ventral extensions of the forebrain ventricles, including parolfactory, amygdaloid, septal, preoptic, hypothalamic and thalamic areas, as well as the dorsal ventricular ridge, the piriform cortex, and midbrain-pontine periaqueductal structures. The general anatomical pattern of distribution of estrogen target neurons corresponds to those observed not only in another reptile (Anolis carolinensis), but also in birds and mammals, as well as in teleosts and cyclostomes. In Pseudemys, which appears to display an intermediate degree of phylogenetic differentiation, the amygdaloid-septal-preoptic groups of estrogen target neurons constitute a continuum. In phylogenetic ascendency, e.g. in mammals, these cell populations are increasingly separated and distinct, while in phylogenetic descendency, e.g. in teleosts and cyclostomes, an amygdaloid group appears to be absent or contained within the septal-preoptic target cell population.

Appearance of LH-immunoreactive cells in the Rathke's pouch of the chicken embryo

The differentiation of the pituitary of the chicken embryo was studied by means of an immunohistochemical technique using antisera to turkey and chicken pituitary hormones. Immunoreactive LH-cells are detected in 4-day embryos (stage 23 of Hamburger and Hamilton) when the primordium of the anterior pituitary, the Rathke's pouch is only composed of a single-layer epithelium lined with an undifferentiated mesenchyme. A few immunoreactive cells are observed grouped on the posterior aspect of the pouch. As development proceeds, a strip of positive cells is detected encircling the Rathke's pouch. Prolactin-, growth hormone-, and ACTH-immunoreactive cells are detected in 6- and 7-day embryos, only after the pituitary has acquired its characteristic structure with cords in which different cell types become progressively recognizable. The early appearance of immunoreactive LH-cells following a precise distribution shows that secretory properties and differentiation capacities are acquired simultaneously in the epithelium of the Rathke's pouch and may be induced by the same stimulus.

Autoradiographic studies with 3H 1,25 (OH)2 vitamin D2 and 3H 25 (OH) vitamin D3 in rat parathyroid glands

After injection of radiolabeled 1,35 (OH)s vitamin D3, nuclear concentration of radioactivity is observed in parenchymal cells o hte parathyroid gland in pregnant, adult male, and 10-day male neonatal rats. In competition studies with unlabeled 1,25 (OH)2 vitamin D3, but not with 25 (OH) vitamin D3, in contrast to 3H 1,25 (OH)2 vitamin D3, do not show nuclear concentration in cells of te parathyroid. The results of te autoradiographic studies suggest the presence of receptors for a direct effect of 1,35 (OH)2 vitamin D3 on the parathyroid gland for modulation of parathyroid hormone secretion.

Androgen target cells in spinal cord, spinal ganglia, and glycogen body of chick embryos. Autoradiographic localization

After injection of 3H dihydrotestosterone, concentration and retention of radioactivity occur in nuclei of certain neurons in the spinal cord and spinal ganglia as well as in dorsal and ventral root cells of chick embryos at day 10, 12, and 18. Cell of the glycogen body show nuclear labeling at day 12, but not at day 18. In motor neurons in the midlumbar and midbrachial regions in lamina IX and in single neurons in laminae I/II, the nuclear retention of androgen is strongest, but relatively weak in ventral horn cells in thoracic and sacral segments. Neurons with nuclear labeling are also found scattered in other laminae of the dorsal and ventral horns as well as in the lateral column. When unlabeled dihydrotestosterone is administered before 3H dihydrotestosterone, nuclear uptake of radioactivity is prevented, which is not the case, when estradiol is used. The results from these autoradiographic studies indicate the presence of nuclear receptors and suggest androgen effects during prenatal stages of development.

[Basis for a specific-active immunotherapy in malignant melanoma]

Since Morton demonstrated in 1968 that malignant melanoma is antigenic, many immunologists have taken an interest in this disease. A basis for specific active immunotherapy has been worked out at Duke University Medical Center, Durham, N.C. (USA). A female chimpanzee was hyperimmunized with melanoma cells grown in tissue culture. After appropriate absorptions the xeno-antiserum was tested by indirect immunofluorescence. Apart from unspecific activities in the serum detectable against normal human fetal and adult fibroblasts as well as other non-melanotic human tumors, following further absorptions with these cells a melanoma-specific antigen could be demonstrated on the surfaces of melanoma cells. The melanoma-specific tumor-associated antigens were further evaluated by direct and indirect immunoautoradiography. These studies suggest that there are indeed cross-reacting specific tumor-associated antigens on the cell surface of melanoma cells. At DUMC melanoma patients have therefore been hyperimmunized with melanoma cells + BCG. Clinical experience is discussed.

(3-H)-dihydrotestosterone in catecholamine neurons of rat brain stem: combined localization by autoradiography and formaldehyde-induced fluorescence

A combined formaldehyde-induced fluorescence (FIF)-autoradiography procedure was used to determine how and where the androgen, dihydrotestosterone (DHT), is associated with catecholamine systems in the rat brain. With this dual localization method, (3H)-DHT target sites can be visualized in relation to catecholamine perikarya and terminals. In the hindbrain, catecholamine neurons adjacent to the fourth ventricle (group A4), the nucleus (n.) olivaris superior (group A5), the n. parabranchialis medialis (group A7), and in the locus coeruleus (group A6) and subcoeruleal regions, as well as in the substantia grisea centralis, concentrate (3H)-DHT in their nuclei. (3H)-DHT target neurons appear to be innervated by numerous catecholamine terminals in the following hindbrain regions: n. motorius dorsalis nervi vagi, n. tractus solitarii, n. commissuralis, n. raphe pallidus, n. olivaris inferior, the ventrolateral portion of the substantia grisea centralis, n. cuneiformis, and the ventrolateral reticular formation in the caudal mesencephalon. In the forebrain, (3H)-DHT concentrates in nuclei of catecholamine neurons located in the n. arcuatus and n. periventricularis (group A12). In addition, (3H)-DHT target neurons appear to be innervated by numerous catecholamine terminals in the following forebrain regions: n. periventricularis rotundocellularis, n. paraventricularis, n. dorsomedialis, n. periventricularis, area retrochiasmatica, n. interstititalis striae terminalis (ventral portion), and n. amygdaloideus centralis. The disclosure of a morphologic association between (3H)-DHT target sites and certain brain catecholamine systems suggests a close functional interdependence between androgens and catecholamines.

Immunohistochemical localization of enkephalin in the central nervous system and pituitary of the lizard, Anolis carolinensis

The topographical distribution of enkephalin in the central nervous system of the lizard, Anolis carolinensis, has been studied by the immunoperoxidase technique with antiserum to leucine-enkephalin. Immunoreactive enkephalin perikarya, fibers and probably terminals are widely distributed throughout the central nervous system, which agrees well with the distribution of enkephalins in the mammalian brain. Enkephalin-containing perikarya are found in the subpallium (septum, nucleus accumbens, striatum, amydgala), preoptic and hypothalamic region, ventromedial nucleus and ventromedial area of thalamus, pretectal geniculate nucleus and posterodorsal nucleus of pretectum, nucleus of the lateral lemniscus, locus ceruleus, spinal trigeminal nucleus, nucleus of the solitary tract, medial parvocellular nucleus, and dorsal horn of the spinal cord. Enkephalinergic fibers and terminals are found in the above-mentioned areas as well as in the pallium (medial and dorsal cortex, dorsal ventricular ridge), dorsomedial and anterior dorsolateral nucleus of the thalamus, habenula, nucleus of the stria medullaris, torus semicircularis, mesencephalic tegmental area, interpeduncular nucleus, mesencephalic trigeminal nucleus, central gray, reticular formation, raphe nucleus, substantia nigra, isthmus region, and nucleus of the trapezoid body. Enkephalinergic pathways appear to exist between the septum and the medial cortex, nucleus accumbens and nucleus of the lateral olfactory tract, striatum and certain mesencephalic structures, hypothalamus and tegmentum, and between nucleus of the lateral lemniscus and torus semicircularis. In the pituitary, cells of the pars intermedia, and certain cells of the rostral pars distalis also show immunoreactivity to enkephalin antiserum. The distribution of enkephalin immunoreactivity throughout the hypothalamus and in the median eminence suggests involvement in neuroendocrine regulation. Presence of enkephalin in many extrahypothalamic brain areas indicates its important role in various sensory functions and in behavioral and autonomic integration.

Effect of 1,25 dihydroxyvitamin D3 on insulin secretion

Recent autoradiographic studies demonstrated that B-cells concentrate 1,25 (OH)2 D3 in their nuclei, suggesting a genomic action on B-cell function. This study was undertaken to investigate the effects of 1,25 (OH)2 D3 on insulin secretion in vitamin D-deficient rats. Mature vitamin D-deficient rats were injected with 1,25 (OH)2 D3 or the ethanol-isotonic saline vehicle. Administration of 1,25 (OH)2 D3 to 10 rats resulted in a 17 microunits/ml (113%) increase in insulin levels and 0.9 mg/dl (16%) increase in plasma calcium. No changes were found in insulin or calcium levels in 5 control rats given vehicle alone. A group of vitamin D-deficient rats with plasma calcium levels of 5.4 +/- 0.1 mg/dl had insulin levels that were the same as those observed in a group of vitamin D-deficient rats with plasma calcium levels of 6.3 +/- 0.1 mg/dl. The difference in calcium levels between these two groups is similar to the increase in plasma calcium found after 1,25 (OH)2 D3 administration. The results of these studies indicate that 1,25 (OH)2 D3 action on pancreatic B-cells affects insulin secretion. Since insulin increases synthesis of 1,25 (OH)2 D3, the existence of a feedback loop between B-cells and kidney proximal tubule cells is suggested.

Autoradiographic studies of estrogen target cells in the forebrain of larval lamprey, Petromyzon marinus

The distribution of estrogen target neurons is assessed in the forebrain of larval sea lamprey, Petromyzon marinus, by the use of thaw-mount autoradiography. Following the injection of [3H]estradiol-17 beta, radioactively labeled neurons are found in the ventral telencephalon and in the ventral and dorsal diencephalon, including preoptic, central hypothalamic, and thalamic regions. In the pallium no labeled cells exist. Pituitary glands, obtained from two of the animals, contain no labeled cells. The topographical distribution of estrogen target neurons in larval lamprey is similar to that of adult animals. The number of target neurons in larval lamprey, however, is lower than in the adult. The presence of target cells indicates that gonadal steroids act on the brain at this early stage of development. The lack of concentration of estrogen in pituitary cells suggests an absence of feedback regulation of estrogen at the pituitary level.

Central noradrenergic neurones concentrate 3H-oestradiol

Central catecholamines play an important part in the regulation of hormone secretion from the pituitary gland and in the mediation of male and female sexual behaviour. Noradrenaline has been shown to stimulate the release of luteinizing hormone (LH) probably by influencing the secretion of LH-releasing hormone (LHRH). The medial preoptic and hypothalamic areas, including the median eminence, contain noradrenaline-containing terminals which originate from discrete noradrenaline-containing cell groups in the lower brain stem. These cell groups have been identified in the pons and the medulla oblongata by histochemical methods and pharmacological experiments. Recent studies with antiserum to dopamine-beta-hydroxylase (DBH), the enzyme that converts dopamine to noradrenaline, provided evidence for the existence of noradrenergic cells. These include the locus coeruleus (group A6), a ventrally located more diffuse but continuous subcoeruleus group (group A5), a cell group located dorsal to the nucleus (n.) dorsalis motorius nervi vagi (group A2) and a cell group in or near the nucleus reticularis lateralis (group A1). Using the thaw-mount autoradiographic technique, oestradiol-concentrating neurones have been localized in many areas of the lower brain stem, including the locus coeruleus, n. tractus solitarii, n. dorsalis motorius nervi vagi, and reticular formation where catecholamine-containing neurones exist. We report here the simultaneous localization, in the same histological section, of 3H-oestradiol and the enzyme dopamine-beta-hydroxylase in neurones of the rat lower brain stem with a combined technique of thaw-mount autoradiography and immunohistochemistry, demonstrating that noradrenaline- or adrenaline-containing neurones are oestradiol target cells.

Quantitative assessment of steroid hormone binding sites by thaw-mount autoradiography

A procedure for the quantitative assessment of nuclear receptors for steroid hormones--and other substances--in individual cells is presented. Thaw-mount autoradiography, a procedure developed earlier in our laboratory, is utilized. The silver grain yield (specific activity) is 16.6 disintegrations per silver as determined fo tritium in guinea pig uterine tissues. An integrated formula is presented and applied for 3H-estradiol, 3H-diethylstilbestrol, and 3H-aldosterone in sampled tissue. A comparison with data derived from the literature that are based on the homogenization of whole uteri and biochemical analysis shows comparable values wtih the autoradiographic data if the latter are pooled. The pooled ata indicated 12-14,00 molecules of 3H-estradiol per uterine nucleus, while subpopulations of target cells vary between 5,000 and 28,000 per nucleus.

1,25-Dihydroxyvitamin D3 target cells in rat mammary gland

In autoradiograms of mammary glands of rats on days 18 and 20 of pregnancy and day 6 of lactation after injection of 3H 1,25-(OH)2 vitamin D3, a nuclear concentration of radioactivity is observed in alveolar and ductal cells, as well as in cells of the epidermis of the nipple. Myoepithelial cells and connective tissue cells do not concentrate the hormone in their nuclei. The nuclear radioactivity appears specific, since 1,25-(OH)2 vitamin D3 but not 25-(OH)2 vitamin D3 prevents the uptake. The results suggest the existence of nuclear receptors for 1,25-(OH)2 vitamin D3 in mammary tissues and thus complements previous biochemical evidence showing the presence of cytoplasmic receptors for the hormone in mouse mammary glands; in addition, our results allow the identification of the cell types possessing the receptors.

Combined autoradiography and immunohistochemistry for simultaneous localization of radioactively labeled steroid hormones and antibodies in the brain

A combined technique of autoradiography and immunohistochemistry is described for localization of radioactively labeled ligands and antibodies to neuropeptides, protein hormones and neurotransmitter synthesizing enzymes in the brain. This method permits the simultaneous visualization of radioactively labeled cells and neuropeptide-producing cells in the same tissue preparation. Autoradiograms are fixed with weak paraformaldehyde solution prior to photographic processing for subsequent immunoperoxidase staining. With this procedure 3H-estradiol is localized in neurophysin I and arginine vasopressin-producing cells of the mouse supraoptic and paraventricular nuclei, neurophysin-producing cells of the guinea pig hypothalamus, and dopamine-beta-hydroxylase-containing neurons of the rat lower brainstem; 3H-dihydrotestosterone in pituitary gonadotropes and thyrotropes; and 3H-1,25-(OH)2 vitamin D3 in pituitary thyrotropes and pancreatic B-cells.

1,25-Dihydroxyvitamin D3 stimulated increase of 7,8-didehydrocholesterol levels in rat skin

A convenient, accurate assay was developed for determining skin cholesta-5,7-dien-3 beta-ol (7,8-didehydrocholesterol) concentrations. Ultraviolet spectrophotometry provided quantitation of the sterol from rat skins following saponification and chromatography on Lipidex and high-performance liquid chromatography. Correction for recoveries was accomplished by using 7,8-didehydro[3 alpha-3H]cholesterol as an internal standard. Chronic dosing of vitamin D-deficient rats with 1,25-dihydroxyvitamin D3 caused a 4-fold increase in skin 7-dehydrocholesterol content. This rise was not the result of changes in food consumption, body weight, or plasma calcium. Cholesterol concentrations were not significantly elevated although some of the other nonsaponifiable lipid components found in the high-performance liquid chromatogram appeared to be increased by the treatment. These results suggest that the vitamin D hormone 1,25-(OH)2D3 may exert a positive feedback regulation on the production of vitamin D3 in skin.