Showing papers on "Pinealocyte published in 1982"
TL;DR: It is suggested that SR formation may be related structurally as well as functionally to adrenergic receptors on the rat pinealocyte, and was not dependent on an intact innervation or the presence of endogenous (pineal) norepinephrine.
Abstract: The formation of pineal ‘synaptic’ ribbons (SR) may be directly related to the adrenergic innervation of the gland. In order to clarify this relationship, SR populations at various times from 12 h to 14 days after pineal denervation were morphometrically analysed by electron microscopy. Pineal denervation was accomplished by bilateral superior cervical ganglionectomy. A decrease in nocturnal pineal SR numbers, indicating a reduction in SR formation, was demonstrated 12 to 24 h after pineal denervation. Seventy-two hours after ganglionectomy SR numbers were comparable with those in nocturnal intact and sham-operated controls. Thereafter, 7 and 14 days after ganglionectomy, SR numbers exceeded nocturnal intact and sham-operated controls. Administration of isoproterenol, a beta-adrenergic receptor agonist, 24 h after denervation significantly increased SR numbers over those in untreated rats denervated 24 h earlier. Thus SR formation remained responsive to adrenergic receptor stimulation in the absence of an intact adrenergic innervation. Further, the increase in SR numbers following subacute (7 to 14 days) denervation indicated that SR formation was not dependent on an intact innervation or the presence of endogenous (pineal) norepinephrine. On the basis of these results, we suggest that SR formation may be related structurally as well as functionally to adrenergic receptors on the rat pinealocyte.
68 citations
Journal Article•
TL;DR: The presence of opsin in the numerous well developed pineal outer segments of these reptilian and avian species contradicts the earlier hypothesis on the gradual regression of pineal sensitive structures in the avian line of evolution.
Abstract: The presence of opsin was investigated with light microscopic immunocytochemistry in pinealocytes of reptiles and birds (Emys orbicularis, Pseudemys scripta elegans, Lacerta agilis et viridis, Gallus domesticus, Columba livia, Melopsittacus undulatus, Serinus canaria, Taeniopyga punctate). The outer segments of pinealocytes selectively bound antiopsin antibody as revealed by indirect immunocytochemical techniques, indicating the occurrence of a rhodopsin-like photopigment in these structures. The results were compared with those obtained in retinal photoreceptors of the same species as well as in the pineal organ of fishes and amphibians (Cyprinus carpio, Carassius auratus, Rana esculenta). Corresponding to immunoreactive structures seen in the light microscope, we found typical outer segments on a large number of pinealocytes in most of the reptiles and birds studied. The presence of opsin in the numerous well developed pineal outer segments of these reptilian and avian species contradicts the earlier hypothesis on the gradual regression of pineal sensitive structures in the avian line of evolution.
45 citations
TL;DR: In Passer domesticus, intrapineal nerve cells were labeled by uptake of microiontophoretically administered horseradish peroxidase (HRP) as discussed by the authors.
Abstract: In Passer domesticus, intrapineal nerve cells were labeled by uptake of microiontophoretically administered horseradish peroxidase (HRP). Unipolar nerve cells with a dichotomously branching stem process are the main source of the dominant pinelaofugal component of the pineal tract, whereas multipolar and bipolar neurons appear to represent interneurons. HRP-labeled nerve fibers are observed in the distal division (end-piece) of the pineal organ; they can be regarded either as processes of intrapineal neurons or projections of pinealopetal axons originating from central neurons. Furthermore, scattered labeled nerve fibers occur in different portions of the pineal stalk. Nerve fibers containing HRP were also demonstrated in the medial and lateral divisions of the habenular complex and in the periventricular layer of the hypothalamus; these axons apparently represent anterogradely labeled pinealofugal elements. On the other hand, retrogradely labeled neurons were found in the medial habenular complex and in the periventricular hypothalamic gray near the paraventricular nucleus, indicating that the pineal organ receives a pinealopetal innervation arising from the central nervous system. Ultrastructurally, the neuropil of the pineal organ of P. domesticus displays single basal processes of pinealocytes containing synaptic ribbons in association with clear synaptic vesicles. Occasionally, conventional synapses were observed the presynaptic terminals of which exhibit granular inclusions. The pineal tract consisting of four to six spatially separated fiber bundles comprises mainly unmyelinated elements accompanied by only few myelinated axons. The functional role of the neural apparatus revealed in the present study is discussed in context with the humoral (hormonal) control of circadian functions; the latter type of activity has been shown to exist in the pineal organ of P. domesticus (Zimmerman 1976).
40 citations
TL;DR: Although MEL and 5-MTL caused fairly similar reactions on average, they appear to act on different cells, as well as 5-HTL, which caused no effect on cells in the visual system.
Abstract: The indoles serotonin (SER), melatonin (MEL), 5-methoxytryptophol (5-MTL) and 5-hydroxytryptophol (5-HTL) were administered during daytime microelectrophoretically to 240 cells in the pineal gland of the guniea-pig. The action of SER and 5-HTL was predominantly depressant on the electrical activity, MEL and 5-MTL caused an excitation in most of the units. Although MEL and 5-MTL caused fairly similar reactions on average, they appear to act on different cells. The effects of microelectrophoretically applied MEL and 5-MTL on the spontaneous or evoked activity in the visual system (retinal ganglion cells, optic tract, lateral lateral geniculate body, superior colliculus) of the guinea-pig were also investigated. Of the 76 cells tested in the visual system 25 of the ON- and OFF-cells increased the rate of discharge when the two indoles were applied. Cells in the optic layer of the superior colliculus showed no measurable response to the application of the two substances. 5-HTL caused no effect on cells in the visual system.
36 citations
01 Jan 1982
TL;DR: The effects of melatonin and other pineal agents in humans are described to provide a better understanding of the gland in brain and endocrine function and the mechanisms involved.
Abstract: Publisher Summary This chapter describes the effects of melatonin and other pineal agents in humans. The pineal gland is an actively secreting endocrine gland that affects diverse aspects of brain and endocrine physiology. A common feature of these glands is that they are usually solid and well-vascularized parenchymatous organs containing characteristic cells termed pinealocytes that have a secretory function. The mammalian pineal gland differs from the saccular pineals of submammalian species that consist of photoreceptor and sensory nerve cells. The pineal contains all the enzymes necessary for catecholamine synthesis and noradrenaline. Studies suggest that in schizophrenia pineal, HIOMT may be out of phase with its normal substrate and may thus act on abnormal substrates to produce the dimethylated metabolites responsible for the disease. Depression, as suggested by many researchers, may result from a deficiency of serotonin or catecholamines or both. Melatonin secretion has been examined in manic and depressive patients because of evidence linking these disorders with derangements in biological rhythms and with an altered noradrenergic activity. Many investigations in the pineal's role in human and mammalian physiology need to provide a better understanding of the same; principal among these are the effects of the gland in brain and endocrine function and the mechanisms involved. The role of the pineal in human circadian periodicity, sleep, and behavior also await elucidation.
30 citations
TL;DR: Exposure of male guinea-pigs to continuous illumination for 45 days resulted in a 25% decrease of pineal volume, the intermediate area being relatively little affected, an increase in the number of follicles and a decrease in pinealocyte nuclear size.
Abstract: In the present study, the proximal, intermediate and distal parts of dumbbell-shaped pineal glands of Pirbright White guinea-pigs were investigated with respect to structural dissimilarities. The most conspicuous difference was that while in the proximal part the pinealocytes were arranged in a random fashion, the intermediate and distal regions, except a small ventral area in the latter, exhibited a prominent follicular arrangement of the pinealocytes. Concretions were restricted to the subcapsular region of the intermediate part, whereas cells with hyperchromatic nuclei increased in number in an anterior-posterior direction. In males, pinealocyte nuclear size did not differ significantly in the regions investigated, whereas in females the karyometric results were much more heterogeneous. Exposure of male guinea-pigs to continuous illumination for 45 days resulted in (i) a 25% decrease of pineal volume, the intermediate area being relatively little affected, (ii) an increase in the number of follicles and (iii) a decrease in pinealocyte nuclear size, especially in a ventral zone of the proximal part of the pineal gland.
24 citations
TL;DR: The post-ganglionic sympathetic nerve fibers and vascular elements were compared in the two age groups and an increase in the number and size of concretions in the aged rat pineal was observed.
Abstract: This study utilized SEM and TEM to demonstrate and compare age-associated changes in pineal morphology of young and senile rats. Structural changes observed in this study and interpreted as age-related included (1) an Increase in the overall thickness of the connective tissue capsule with age, (2) an increase in the relative number of connective tissue cells and fibers in the aged pineals, (3) an increase in the number of striated muscle fibers in the connective tissue capsule and pineal parenchyma, (4) increased number of vacuoles, dense vesicles and dense bodies in pinealocytes, (5) mitochondria with dense cores and longitudinally arranged cristae, (6) an increase in size of cytoplasmic lipid droplets and presence of interstitial adipose lobules, (7) the presence of myelin-like figures in the stalk of the pineal gland and (8) an increase in the number and size of concretions in the aged rat pineal. In addition, the post-ganglionic sympathetic nerve fibers and vascular elements were also compared in the two age groups.
23 citations
Journal Article•
TL;DR: An increase in the number of 'synaptic' ribbons after superior cervical ganglionectomy supports the hypothesis that adrenergic innervation of the pineal gland influences the level of ' synaptic' ribbon formation.
Abstract: The dense-core vesicles and 'synaptic' ribbons were counted in Djungarian hamster pinealocytes after superior cervical ganglionectomy. Sympathectomy caused a decrease in the number of dense-core vesicles in pinealocytes, suggesting diminished secretory activity of these cells. An increase in the number of 'synaptic' ribbons after superior cervical ganglionectomy supports the hypothesis that adrenergic innervation of the pineal gland influences the level of 'synaptic' ribbon formation.
21 citations
TL;DR: The pineal system of the Mongolian gerbil was investigated by light and electron microscopy, special attention being paid to the sites of contact with the ventricular system, revealing a specific topographical relationship to the suprapineal recess of the third ventricle.
Abstract: The pineal system of the Mongolian gerbil (Meriones unguiculatus) was investigated by light and electron microscopy, special attention being paid to the sites of contact with the ventricular system. The results reveal that the pineal system of this species has a specific topographical relationship to the suprapineal recess of the third ventricle. The dorsal side of the proximal part of the pineal system forms the floor and the caudal wall of this recess. Here, a consistent and relatively large area lacks an ependymal lining, enabling pinealocytes to come into direct contact with the cerebrospinal fluid (CSF). This area is assumed to be the morphological correlate of a close functional interrelationship between the pineal tissue and the CSF.
18 citations
TL;DR: The ultrastructure of the pineal gland of the fox was examined and compared with that of other mammals.
Abstract: The ultrastructure of the pineal gland of the fox was examined and compared with that of other mammals. The pineal gland of the fox is composed of two different populations of pinealocytes (I and II). The pinealocytes I were distributed homogeneously throughout the parenchyma, while pinealocytes II were located generally near blood vessels. A Golgi apparatus, granular endo-plasmic reticulum, mitochondria, lysosomes, centrioles, and cilia were present in both cell populations. A characteristic feature of pinealocytes I was the presence of dense-core vesicles, presumably of Golgi origin; whereas glycogen deposits and pigment granules were common features of pinealocytes II. In addition to the pinealocytes, the parenchyma contained fibrous astrocytes. The capillaries of the pineal gland of the fox consisted of a nonfenestrated endothelium. Numerous nerve fibers, presumably adrenergic, were observed throughout the parenchyma.
17 citations
TL;DR: Although hypophysectomy appeared to diminish the general activity of pinealocytes, it stimulated the neurosecretory-like secretory process Golgi apparatus-dense-core vesicles, whereas prolactin appeared to stimulate the ependymal-likesecretory process (granular endoplasmic reticulum-vacuoles containing a flocculent material).
Abstract: The effects of hypophysectomy and prolactin administration on the ultrastructure of rat pinealocytes were studied by means of morphometric analysis. Hypophysectomy resulted in an increase in the Golgi apparatus and dense-core vesicles and a decrease in the granular endoplasmic reticulum, lysosomes and lipid droplets. Prolactin administration induced an increase in the granular endoplasmic reticulum and in the vacuoles which contained a flocculent material. Administration of prolactin to hypophysectomized rats raised the lowered levels of granular endoplasmic reticulum and lipid droplets to control values and caused an increase in vacuoles containing a flocculent material. Although hypophysectomy appeared to diminish the general activity of pinealocytes, it stimulated the neurosecretory-like secretory process Golgi apparatus-dense-core vesicles), whereas prolactin appeared to stimulate the ependymal-like secretory process (granular endoplasmic reticulum-vacuoles containing a flocculent material).
TL;DR: The ultrastructure of the pineal parenchymal cells, pinealocytes and glia-like cells, of the Chinese hamster is described and is characterized by the presence of abundant lipid droplets and occasional pigment granules.
Abstract: The ultrastructure of the pineal parenchymal cells, pinealocytes and glia-like cells, of the Chinese hamster (Cricetulus griseus) is described. Pinealocyte nuclei contain spindle-shaped inclusions consisting of bundles of closely packed parallel filaments of about 8 nm in thickness. Mitochondria contain lamellar and tubular cristae. Smaller and larger mitochondria are usually localized separately in individual pinealocytes. Flattened mitochondria contain two to four closely arranged, unusual lamellar cristae, which lie parallel to the surface of the mitochondria. These cristae exhibit particular structures. Rough endoplasmic reticulum is frequently found in close association with such flattened mitochondria. Tubular expansions of the outer membrane of mitochondria occur frequently. The pinealocyte cytoplasm contains stacks of flattened cisternae, which are continuous with both smooth and rough endoplasmic reticulum. Pinealocyte cell bodies and processes contain granulated vesicles. Although larger granulated vesicles measuring up to 300 nm in diameter occasionally occur, smaller granulated vesicles (about 100 nm in diameter) and larger ones are usually localized separately in individual cells. Vacuoles containing flocculent material are found in groups in close association with rough endoplasmic reticulum. Glia-like cells with darker cytoplasm and nuclei lie surrounding pericapillary or intercellular spaces. The glia-like cells are characterized by the presence of abundant lipid droplets and occasional pigment granules. Bundles of filaments run parallel to the long axis of the processes of the glia-like cells.
TL;DR: A diurnal rhythm was found in the total amount of the neuron-specific phosphoprotein protein I in rat pinealocytes, and β-Adrenergic neurotransmission appears to be the mechanism regulating the amount of pinealprotein I in vivo.
Abstract: A diurnal rhythm was found in the total amount of the neuron-specific phosphoprotein protein I in rat pinealocytes. β-Adrenergic neurotransmission appears to be the mechanism regulating the amount of pineal protein I in vivo.
TL;DR: Observations suggest a possible age-associated decrease in the neurosecretory-like (but not ependymal-like) secretory process in the pinealocyte of white-footed mice.
Abstract: Quantitative comparison of pinealocyte ultrastructure in 3-month-old and 28-month-old male white-footed mice (Peromyscus leucopus) revealed decreases both in the area of the Golgi apparatus and in the number of dense-core vesicles. In contrast, no differences between these two age groups were noted in the areas of granular endoplasmic reticulum, vacuoles with flocculent content, lysosome-like bodies, or mitochondria. Nor were any changes between groups of mice apparent in pinealocyte nuclear or cytoplasmic areas, nuclear: cytoplasmic ratios, or the number of pinealocyte nuclei per unit area. Areas of unusual, annulate lamellae-like structures were increased in the pinealocytes of a group of 28-month-old mice. These observations suggest a possible age-associated decrease in the neurosecretory-like (but not ependymal-like) secretory process in the pinealocyte of white-footed mice.
TL;DR: The extraordinary ultrastructural feature of the chipmunk pinealocyte was the presence of extremely large numbers of “synaptic” ribbons, which exceeded by a factor of five to 30 times that found in any species previously reported.
Abstract: The ultrastructure of the pineal gland of the wild-captured eastern chipmunk (Tamias striatus) was examined A homogenous population of pinealocytes was the characteristic cellular element of the chipmunk pineal gland Often, pinealocytes showed a folliclelike arrangement Mitochondria, Golgi apparatus, granular endoplasmic reticulum, lysosomes, centrioles, dense-core vesicles, clear vesicles, glycogen particles, and microtubules were consistent components of the pinealocyte cytoplasm The extraordinary ultrastructural feature of the chipmunk pinealocyte was the presence of extremely large numbers of "synaptic" ribbons The number of "synaptic" ribbons in this species exceeded by a factor of five to 30 times that found in any species previously reported In addition to pinealocytes, the pineal parenchyma contained glial cells (oligodendrocytes and fibrous astrocytes) Capillaries of the pineal gland of the chipmunk consisted of a fenestrated endothelium Adrenergic nerve terminals were relatively sparse
TL;DR: The results of the present study demonstrate the influence of the adenohypophysis on the pineal gland and these data, together with the known influence ofThe pineal glands on the adeniophysis, support the existence of a reciprocal relationship between these two glands.
Abstract: The ultrastructure of the pinealocytes of Snell dwarf mice (dw/dw) was examined morphometrically and compared with that of both phenotypically normal (dw/+ or +/+) animals of the same strain and dwarf mice with ectopic pituitary grafts. Ultrastructural features characteristic of diminished activity of the pinealocytes were observed in dwarf mice as compared with controls. Ectopic pituitary grafts induced morphological signs of activation of the pinealocytes in this mutant. The results of the present study demonstrate the influence of the adenohypophysis on the pineal gland and these data, together with the known influence of the pineal gland on the adenohypophysis, support the existence of a reciprocal relationship between these two glands.
Journal Article•
TL;DR: The results of the present study suggest that the pineal gland may play a subtle role in pregnancy.
Abstract: The numbers of Golgi profiles, dense-core vesicles, vacuoles containing a flocculent material, lysosomes, lipid droplets, 'synaptic' ribbons and microtubular sheaves were counted in the rat pinealocytes in the last 5 days of pregnancy. The numbers of Golgi profiles and dense-core vesicles increase at days 21 and 22, while numbers of LYS and LD increase the day before parturition. On the contrary, the number of VFC decreases in the final day of pregnancy. The results of the present study suggest that the pineal gland may play a subtle role in pregnancy.
TL;DR: It is suggested that norepinephrine releases PGE2 in rat pineals via alpha-adrenoceptors, acting at a post-synaptic site, and that superior cervical ganglionectomy induces alpha- adrenergic supersensitivity in the pinealocytes.
TL;DR: The pineal gland of the kangaroo rat appears to be a good model for the study of the potential relationship between these two secretory processes, especially in respect to seasonal changes.
Abstract: The ultrastructure of the pinealocytes of the wild-captured ord kangaroo rat (Dipodomys ordi) was examined. A homogeneous population of pinealocytes was present in the pineal gland of the kangaroo rat. The Golgi apparatus, granular endoplasmic reticulum, mitochondria, lysosomes, dense-core vesicles, vacuoles containing a flocculent material and lipid droplets were consistent components of the pinealocyte cytoplasm, whereas infrequently-observed organelles included centrioles, multivesicular bodies, subsurface cisternae, “synaptic” ribbons and cilia. The number of dense-core vesicles was relatively high and dense-core vesicles and vacuoles containing a flocculent material were present in the same cell.
TL;DR: The present ultrastructural study supports the conclusion that tree shrew pineal organ is an endocrine gland which is heavily innervated by adrenergic nerves and possibly by cholinergic nerves.
Abstract: The fine structure of the pineal gland and the pineal innervation in the tree shrew were studied by electron microscopy and glyoxylic acid-induced fluorescence microscopy respectively. The parenchymal cells consist of pinealocytes, glial cells and pigment-containing cells. The pinealocytes are characterized by the presence of granular vesicles, synaptic ribbons, electron-dense bodies and small profiles of rER with dilated cisternae. Glial cells contain light cytoplasmic bodies, lipofuscin granules, bundles of microfilaments, and elongate profiles of rER with flattened cisternae which are often stacked together with light cytoplasmic bodies; the pigment-containing cells are unique in possessing giant pigment granules in the cytoplasm. The pinealocyte/glial cell/pigment cell in tree shrew pineals may be the same cell line of parenchymal cells at different ontogenetic stages. Pigment-containing cells contain pigment granules as a prominent cytoplasmic inclusion, suggesting they are senscent in secretory function. Both pinealocytes and glial cells contain structures suggesting secretory function such as welldeveloped Golgi complex and granular vesicles. The antigonadotrophic substances may be stored in granular vesicles. The present ultrastructural study supports the conclusion that tree shrew pineal organ is an endocrine gland which is heavily innervated by adrenergic nerves and possibly by cholinergic nerves.
01 Jan 1982
TL;DR: An attempt was made to characterize the pinealocytes electro-physiologically, showing the importance of the mammalian pineal as a neurotransducer, and of the limited usefulness of the methods used.
Abstract: Although the mammalian pineal gland has been extensively studied by biochemical, pharmacological and morphological techniques, the precise nature of the intrinsic cells, the pinealocytes, was unknown for a long time. Biochemically the pinealocyte has been shown to be an endocrine cell synthesizing melatonin and other hormones. In view of the importance of the mammalian pineal as a neurotransducer, and of the limited usefulness of the methods mentioned, an attempt was made to characterize the cells electro-physiologically.
TL;DR: A cytoplasmic area occupied by microtubular sheaves, numerous microtubules, groups of microfilaments and Golgi complex is described in rat pinealocytes to experiment a larger development after estradiol administration and castration.
TL;DR: The present study demonstrates the absence of a circadian rhythm in PGV content in hamsters “functionally pinealectomized” by maintenance under long photoperiod (L/D=14/10 h).
Abstract: Previous studies in rabbits and mice have revealed distinct circadian rhythms in the number of pinealocyte granulated vesicles (PGVs) and control of their synthesis and/or secretion by sympathetic nerves. The present study demonstrates the absence of a circadian rhythm in PGV content in hamsters “functionally pinealectomized” by maintenance under long photoperiod (L/D=14/10 h). On the other hand, a highly significant rhythm of low amplitude was noted in PGVs of hamsters placed in photoperiods (<12.5 h) which are known to initiate pineal antigonadotropic activity. Bilateral optic enucleation, which also leads to pineal-mediated gonadal atrophy in the hamster, produced a significant decrease in the number of perivascular PGVs when compared to intact control animals. Daily late afternoon injections of melatonin produced no significant difference in the number of PGVs between treated and control animals at any sample time examined.
Journal Article•
TL;DR: Intermale aggression by pairing bandicoot rats (Bandicota bengalensis) in their home cage, continuously for three hours, stimulated the pineal gland activity, cytologically measured by decreasing cell population density and increasing nuclear size of the Pinealocytes, in the socially subordinate animals.
Abstract: Intermale aggression by pairing bandicoot rats (Bandicota bengalensis) in their home cage, continuously for three hours, stimulated the pineal gland activity, cytologically measured by decreasing cell population density and increasing nuclear size of the pinealocytes, in the socially subordinate animals. The pineal gland of the dominant animal was not perceptibly affected by aggression. It is suggested that during aggression, the subordinate rats perhaps suffered from psychosocial stress that might have caused hyperactivity of their pineal gland.
Journal Article•
TL;DR: A high degree of vascularity, extent of neural innervation, pinealocyte organelles, and presence of extensive pinealocytes and neuroglial cells, as well as numerous neuron cell processes and nerve endings, indicate an active secretory function in the pineal gland of the mink.
Abstract: The pineal gland of the mink (Mustela vison) was examined, using light and electron microscopy. Its cellular structure was compared with that of the pineal gland in other mammalian species, including that of a close taxonomic relative, the ferret. The pineal gland of the mink was composed to pinealocytes and neuroglial cells, as well as numerous neuron cell processes and nerve endings, which provide extensive neural input to the pineal gland. A high degree of vascularity, extent of neural innervation, pinealocyte organelles, and presence of extensive pinealocyte processes with secretory granules indicate an active secretory function. This secretory function is postulated to be associated with the onset of the yearly reproductive cycle in the mink.
TL;DR: Dense-core vesicles, 90–200 nm in diameter, were found in pinealocytes of the cat and were present both in perikarya and cell processes.
Abstract: Dense-core vesicles, 90–200 nm in diameter, were found in pinealocytes of the cat. They were present both in perikarya and cell processes.
TL;DR: Day‐night differences in the areas of granular endoplasmic reticulum, Golgi apparatus, dense‐core vesicles, and lysosomelike bodies were analyzed morphometrically in the pinealocytes of the chipmunk, suggesting the existence of 24‐hour rhythms in the area of these structures.
Abstract: Day-night differences in the areas of granular endoplasmic reticulum, Golgi apparatus, dense-core vesicles, and lysosomelike bodies were analyzed morphometrically in the pinealocytes of the chipmunk. The area of lysosomelike bodies was greater at night and lower during the daytime. In contrast, the areas of granular endoplasmic reticulum and dense-core vesicles were greater during daytime and lower at night. Our observations suggest the existence of 24-hour rhythms in the areas of these structures, perhaps indicative of a pineal rhythm in secretion, whether indolic or peptidergic.
TL;DR: It is concluded that clinical importance exists in anterior pituitary insufficiency with adrenal atrophy, but hyperfunction of the hypophyseoadrenal system might occur during the course of the disease.
Abstract: Autopsy series of 19 patients with pineal and anterior third ventricle (suprasellar) tumors were analyzed with regard to shift in pituitary-adrenal axis. Germinomas formed the most common subgroup in this series (79%). Metastatic tumor growth in the pituitary gland caused adrenal atrophy in 4 cases. Some patients with pineal neoplasms had larger adrenal8 in weight compared with age- and sex-matched controls of Japanese. In three patients with sexual precocity, adrenal weight was larger. It is concluded that clinical Importance exists in anterior pituitary insufficiency with adrenal atrophy, but hyperfunction of the hypophyseoadrenal system might occur during the course of the disease. ACTA PATHOL. JPN. 32: 925- 931,1982. Intvoduction Human pineal seems to be one of the vestigial organs from the viewpoint of vertebrate orthogenesis, because in the phylogenetically advanced animals the structures for visual perception tend to decrease in quantity and in qualit~.~P However, the human pineal organ has a very rich capillary net-work in the interstitial tissue and has sophisticatedly differentiated pinealocytes in the parenchymal lobulesB, the appearance of which can be shown distinctly by del Rio-Hortega's meth~d.~ Morphological survey on pineal phylogeny16 strongly suggests that the pineal is a sense organ in the lower vertebrate, e.g. parietal eye of lizard, and has an endocrine or neuroendocrine function in the higher animals. Since HEUBNER reported precocious puberty in a pinealoma much work has being done on the pineal-gonadal axis by biologists and others.ao Animal experiments have suggested the role of the pineal in the regulation of the other organs of internal secretion.ll,l0 Recently, we investigated the relationship between pineal and adrenal cortex morphometrically.1° The aim of this paper is to estimate the tendency to adrenal weight change in the patients died of pineal region tumors, and to speculate the possible mechanism of its endocrine manifestations.
TL;DR: In the present study the rare occurrence of intramitochondrial crystalloid inclusions in the rat pinealocytes is described, which lie within the mitochondrial matrix and consist of a lattice of moderately electron-dense lines.
Abstract: In the present study the rare occurrence of intramitochondrial crystalloid inclusions in the rat pinealocytes is described. They lie within the mitochondrial matrix and consist of a lattice of moderately electron-dense lines. Intersections at regular intervals form rhomboid-like subunits. The significance of these inclusions is not known.