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1.
Summary The preoptic area of the domestic fowl (Gallus gallus) was studied by means of the Golgi technique. At least two regions can be recognized: (i) a medial and (ii) a lateral area, clearly distinguishable laterally from the adjacent telencephalic regions. The dendritic organization of the preoptic area is quite uniform. The neurons can be classified as isodendritic elements. The magnocellular elements are few and irregularly scattered mostly in the periventricular grey of the medial preoptic area. Of relevant interest is also the observation of some bipolar and horizontal neurons in the dorsal part of the medial preoptic area, near the anterior commissure.  相似文献   

2.
Summary The ultrastructure of the thyroid gland of the domestic fowl has been investigated and found to be similar to that of mammals. The differences were found at subcellular level in the distribution of the dark bodies which were mainly apical and in the sizes of primary lysosomes. These were found to range from 100 to 500 nm in diameter. All organelles described in mammals as being concerned with the production of thyroglobulin and the two hormones thyroxine and triiodothyronine were found to be present.  相似文献   

3.
Summary The corticotropin-releasing factor (CRF)-containing neurons were investigated in the brain of the domestic fowl by means of the peroxidase-antiperoxidase technique at the light-microscopic level. The detection of CRF-immunoreactivity was facilitated by silver intensification. CRF-containing perikarya were found in the paraventricular, preoptic and mammillary nuclei of the hypothalamus and in some extrahypothalamic areas (nuclei dorsomedialis and dorsolateralis thalami, nucleus accumbens septi, lobus parolfactorius, periaqueductal gray of the mesencephalon, nucleus oculomotorius ventralis). Immunoreactive nerve fibers and terminals were demonstrated in the external zone of the median eminence and the organum vasculosum of the lamina terminalis. These results indicate that an immunologically demonstrable CRF-neurosecretory system also exists in the avian central nervous system.  相似文献   

4.
Summary The location of LHRH-containing neuronal elements was investigated in the domestic fowl by means of immunohistochemical techniques. LHRH antisera were raised against synthetic LHRH in the rabbit. The antiserum used in the present study cross-reacted with LHRH of mammalian and avian tissues.LHRH-immunoreactive perikarya are located in the preoptic and in the septal areas, and in the bulbus olfactorius; however, no LHRH-immuno-reactive perikarya were found in the tuberal part of the hypothalamus. LHRH-immunoreactive fibers course from these areas toward the median eminence mainly along the wall of the third ventricle in the form of a periventricular network. Originating from the same cell groups other fibers run caudally immediately above the optic chiasma, forming the median bundle of the tractus preoptico-infundibularis. The third bundle running toward the OVLT is named the tractus preoptico-terminalis. In addition to these structures, LHRH-containing fibers and terminals were also present in different regions of the limbic system, in the dorsal part of the hippocampus, in the tuberculum and bulbus olfactorius, as well as in the optic lobe, nuclei commissurales tectales, organon subcommissurale, periaqueductal area, and pars ventralis mesencephali.The general distribution of the LHRH system in the chicken corresponds principally to that described previously in rodents (Sétáló et al. 1976, 1978). However, some subtle differences were demonstrated between the location of the LHRH system in birds and mammals.  相似文献   

5.
Summary The ultrastructure of the polymorphic vesicular component of the ultimobranchial gland of the domestic fowl (Gallus gallus domesticus) has been described in detail, together with the structure of the cell strands interconnecting the vesicles and the parathyroid nodules lying within the ultimobranchial stroma. The vesicles frequently appear to arise from the nodules by way of the cell strands. The strands show a structure of their component cells intermediate between that of the parathyroid and the vesicular cells, although the position at which the strand changes from an essentially parathyroid structure to an essentially vesicular structure is very variable. The degree and kind of secretory activity within different cell types has been described. A review of the structure of ultimobranchial glands throughout the vertebrates shows that similar tissue with a similar secretory potential has been observed in all vertebrate classes, suggesting a functional significance for this part of the gland.  相似文献   

6.
Summary An ultrastructural study was made of the neurons, satellite cells and vesiculated axons of the intestinal nerve of the domestic fowl. Broad membrane-to-membrane contacts between adjacent nerve cell bodies were sometimes observed. The cell bodies and processes were not always separated from the extracellular space by a capsule of satellite cells. Following fixation using potassium permanganate, catecholamine (CA)-containing neurons in the intestinal nerve, unlike those in the lumbar parasympathetic ganglia, did not possess any small granular vesicles (SGV). Following exposure to noradrenaline, SGV could be demonstrated in the cell bodies of the juxta-ileal ganglia but not the juxta-rectal ganglia of the intestinal nerve. Non-CA axons were examined in tissue from birds that had been pretreated with 6-hydroxydopamine. Approximately one half of the non-CA axons formed axo-somatic contacts. Most of the non-CA axons contained varying proportions of small clear vesicles, large clear vesicles and large granular vescles. Statistical analysis showed that the non-CA axons could not be subdivided according to their vesicle content. CA-axons contained many SGV and were found in close apposition to neuronal somata and processes, and in the neuropil.  相似文献   

7.
Summary Processes of magnocellular neurosecretory cells (MNCs) are easily identifiable on the basis of their content in neurosecretory granules in the neuropil of the rostral division of the paraventricular nucleus (PVN) of the domestic fowl. In specimens sacrificed during the winter the synaptic organization of the neuropil and the pattern of synapses ending on neurosecretory processes were studied at the ultrastructural level. Synapses in the rostral part of the PVN neuropil may be divided into three main categories on the basis of their morphology and their content of clear and dense-core synaptic vesicles. These different types of terminals can be attributed to aminergic, peptidergic or other types of synapses. The percent distribution of synapses within these categories differs when all synapses observed in the neuropil or only those ending on MNC processes are compared. Present ultrastructural data obtained in birds support two physiological hypotheses already suggested for mammals, i.e., the probable existence of a recurrent pathway to MNCs via an interneuron, and the importance of aminergic and peptidergic input in regulating the electrical activity of MNCs.This work was partly supported by a CNR grant (n. 81.00377.04)  相似文献   

8.
Neuronal characteristics and location of the neurosecretory, magnocellular, fuchsin-paraldehyde-positive (FA+) system of the fowl are described at the light-microscopic level on serial semithin sections. Three nuclei make up this system, the nucleus supraopticus, n. magnocellularis interstitialis and n. paraventricularis. These nuclei display magnocellular neurons, not showing a parvocellular component. The neurons of the three nuclei showed a scattered pattern of distribution and a dense surrounding neuropil. Groups formed by magnocellular neurons were found in the three nuclei and groups formed by one magnocellular and a parvocellular neurons were only found in the n. magnocellularis interstitialis and in the n. paraventricularis. The presence of neurons in apposition to blood vessels was frequent in the magnocellular FA+ system of the domestic fowl.  相似文献   

9.
Summary Numerous secretory parvocellular perikarya were found in the preoptic region of the domestic fowl (Gallus gallus). The dense-core secretory vesicles belong to two categories: vesicles with a diameter of (i)80–90 nm and (ii) 110–140nm. Scattered magnocellular elements display larger dense-core granules. The parvocellular neurons form unit-like clusters, showing also zones of direct apposition of neuronal membranes. The surrounding neuropil is rich in synaptic structures, formed by at least three types of axon terminals, distinguishable on the basis of vesicular morphology. These observations confirm the findings in other avian species. The hypothetical function of this system of peptidergic neurons in the rostral hypothalamus of birds is discussed.  相似文献   

10.
Summary In the central nervous system of the male domestic fowl, met-enkephalin (ENK) immunoreactive perikarya and fiber tracts as well as extensive but sharply delimited fiber networks were visualized by means of the PAP technique. The most striking results were: (1) The demonstration of an association of ENK-containing structures with branchial nerves; (2) the spatial relationship of ENK-containing perikarya and fibers to somatostatin (SOM) and arginine-vasotocin (AVT)-immunoreactive systems; (3) the presence of dense and extensive ENK fiber networks within (a) the caudo-basal wall of the third ventricle and (b) the septal-preoptic area; in both regions mainly ENK fibers, but also SOM and AVT fibers, may cross to the contralateral side.  相似文献   

11.
12.
Summary The ultrastructure of the ependymal cells in the area postrema of the domestic fowl was studied by scanning and transmission electron microscopy. The ependymal surface of the area postrema is covered with many furrows and ridges. These ridges consist of ependymal cells aggregated in a fan-like shape. The ependymal cell lacks clustered cilia, microvilli are few, and a long basal process extends through the parenchymal layer of the area postrema. Within the cytoplasm as well as in the basal process, a spherical body with a diameter ranging from 1.5 to 2 gmm is occasionally observed.This work was supported by a Scientific Research Grant, No. 144017, from the Ministry of Education of Japan to Professor M. YasudaThe authors are grateful to Drs. T. Fujioka and T. Watanabe for their valuable advice  相似文献   

13.
the presence of endocrine cells and nerves in the lung of 2 avian species (Gallus gallus and Columba livia domestica) has been studied by peroxidase-antiper-oxidase (PAP) and avidin-biotin complex (ABC) immunocytochemical methods at the light-microscopic level. Two immunoreactive cell-types have been identified in the epithelium of the primary and secondary bronchi of chick lung: serotonin- and bombesin-immunoreactive cells; and 3 cell-types, namely, serotonin-, bombesin- and CGRP-(calcitonin gene related peptide) immunoreactive cells, have been located in the bronchial epithelium of pigeon lung. Co-localization of 2 different immunoreactivities within the same cell has not been detected. VIP-immunoreactive nerves have been observed in different locations in chick lung.  相似文献   

14.
Summary The development of neurophysin-oxytocin and neurophysinvasopressin containing neurons of the guinea pig was studied in vitro. Supraoptic (SO) and paraventricular (PV) nuclei were explanted from guinea pig foetuses at the 40th day of gestation and cultured in Maximov slides for nearly fifty days. The cultures were observed daily under a phase-contrast microscope. Explants were fixed every five days for observation with the electron microscope. At the time of explantation, magnocellular neurons were still immature. They acquired the morphologic characteristics of mature neurons, with axosomatic synapses, after about 10 days in vitro. After 15–20 days in vitro, they contained in addition neurosecretory granules (NSG), first in the Golgi region, then also dispersed in the cytoplasm. In the oldest culture (45–50 days), signs of granulolysis were regularly found. It appears that magnocellular neurosecretory neurons are able to differentiate in vitro from a primitive state in the absence of specific stimulation.The authors are indebted to M.J. Drian for help with tissue culture, and to D. Le Cren for photographic work  相似文献   

15.
Summary The developing outer layer of the vitelline membrane of the ovum in the posterior part of the infundibulum of the domestic fowl contains many spermatozoa in nearly parallel orientation with its inner layer. When the acrosomal region of a spermatozoon approaches or contacts the inner layer, promptly undergoes the acrosome reaction. The outer acrosomal membrane and overlying plasma membrane fuse together and the apical region of the acrosome opens, so that the acrosomal contents are released. Meanwhile the spermatozoon remains a time in contact with the surface of the inner layer, and the network of the inner layer just under the tip of the sperm head begins to be dissolved. This dissolution extends downward forming a tunnel, approximately 9 m in diameter. The spermatozoon then passes through the inner layer obliquely via the central region of the tunnel and arrives at the perivitelline space.The authors are greatly indebted to assoc. prof. Dr. Osamu Koga for his valuable advices. The authors also wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices. This investigation was supported by a grant from the Ministry of Education of Japan (156185)  相似文献   

16.
Summary A ganglion-like aggregate consisting of acetyl-cholinesterase-positive neurons was demonstrated in the pineal organ of the domestic fowl by means of light and electron microscopy. This ganglion is located in juxtaposition with the pineal tract at the posterior (caudal) aspect of the pineal stalk. Numerous large and small neurons formed the ganglion in 40-day-old domestic fowl. Some of these nerve cells established direct neuro-neuronal contacts, others were surrounded by satellite cells. These ganglion cells displayed axo-somatic and axo-dendritic synapses. The above-mentioned cluster of nerve cells may be considered as a pineal ganglion. Its central or peripheral nature is open to discussion. Send offprint requests to: Dr. K. Wake, Department of Anatomy, Faculty of Medicine, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, 113, Japan  相似文献   

17.
Summary Surface features of the ependymal linings of the fourth ventricle in the fowl were analyzed employing the scanning electron microscope (SEM). On the floor of the median sulcus, each ependymal cell has a solitary cilium, whereas on both sides of the sulcus, cilia are so densely distributed that the details of the underlying cell surface are usually obscured. On the roof of the fourth ventricle, except for the surface of the ciliated groove where numerous cilia are present, the ependymal cells are polygonal in shape, and the center of each cell possesses an aggregate of ten to twenty cilia. Cell surfaces of the choroid tela are entirely covered with delicate microvilli and possess clumped cilia. The ependymal cell surfaces of the area postrema are dome-like in shape. Each ependymal cell has a solitary cilium and shows a smooth surface free of microvilli.This work was supported by a Scientific Research Grant, No. 144017, from the Ministry of Education of Japan to Professor M. Yasuda  相似文献   

18.
Summary The ultrastructure of the somatotrophs of the caudal pituitary of the domestic fowl was studied quantitatively. Two age groups of male chickens were compared: 4–6 weeks and 24–30 weeks post-hatching. With age, somatotrophs decreased from about 40% to about 30% of the pituitary cell population. Their volume density decreased similarly. Mean volume of a somatotroph was the same in young and adult animals. Because the granule volume density of the somatotrophs was unchanged, but the somatotroph volume density of the gland declined, the granule volume density of the caudal pituitary gland dropped in parallel with that of the somatotrophs. Thus the volume of the gland comprised of somatotroph granules fell about 32%: from 6.57% to 4.45%. This lowered pool of stored hormone may be linked to the lowered circulating levels of growth hormone found in older animals by other investigators.The granule volume density of the somatotrophs was unchanged but the numerical density approximately doubled; thus the mean granule size decreased by 47% with age. The relationship of the size reduction of the granules to the lowered plasma growth hormone levels is not understood at present.Supported in part by Hatch and State funds from the New Jersey State Agricultural Experimental Station and NSF grants PCM 8,0227,27 and PCM 8,302197.  相似文献   

19.
Summary The somatotrophs of the pituitary gland of the male domestic fowl were identified by means of an immuno-electron-microscopic method based on gold as the electron-opaque label and an antibody to growth hormone. Gold particles indicating sites of growth hormone were restricted to cells in which virtually all of the granules were labelled. Little, if any, gold label was found outside the granules in these cells designated as somatotrophs, or at sites outside these cells. The size of these gold-labelled secretory granules presumed to contain growth hormone decreased with age, from a mean sectional diameter of 256±6.2 nm (SEM) at 4–6 weeks to 221±5.7 nm at 11–18 weeks and 205±8.6 nm at 24–30 weeks of age. On the basis of these values for mean sectional diameters the change between the first two periods represents a decrease in granule volume of about 36%. However, during the same period the growth hormone concentration of the granules increased. Accordingly, growth hormone content per granule changed little if at all. In contrast, from 11–18 weeks to 24–30 weeks of age there was a decrease of 31% in growth hormone content per granule. These data indicate that growth hormone packaging in the chicken somatotroph changes with age. The first change results in the production of smaller granules of higher growth hormone concentration. During this period growth hormone content per granule remains relatively constant. The later change results in the production of granules of lower growth hormone content than that of younger animals.This is a paper of the Journal Sciences, New Jersey Agriculture Experimental Station supported in part by the State and Hatch Act Funds and a grant from the National Science Foundation (PMC-8022727)  相似文献   

20.
Summary The innervation of blood vessels in the brood patch (thoracic skin) of the domestic fowl was studied by use of the catecholamine fluorescence technique, acetylcholinesterase staining, and the immunoperoxidase technique for demonstration of vasoactive intestinal polypeptide (VIP). Large arteries and veins were sparsely innervated, whereas arteriovenous anastomoses (AVAs) were densely innervated by adrenergic, acetylcholinesterase-positive, and VIP-immunoreactive nerve fibres. The rich supply of different vasomotor nerves to AVAs emphasizes the importance of these vascular shunts in regulating blood flow and, in turn, the transport of heat to the brood patch. Furthermore, the presence of VIP-immunoreactive nerve fibres in the vasculature of the brood patch suggests that VIP might be the mediator of the previously reported cold-induced vasodilatation.  相似文献   

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