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S Hisano

Publications and source records attributed to S Hisano.

At least 127 records · Page 7Linked to original sources
PubMed1986

Immunocytochemical evidence for synaptic regulation of paraventricular vasopressin-containing neurons by substance P.

Employing a combination of pre-embedding peroxidase-antiperoxidase-labeling for substance P (SP) and postembedding immunogold labeling with protein A-colloidal gold-anti-arginine vasopressin (AVP) complex, we demonstrated immunoreactive SP containing nerve fibers, which terminate synaptically on the perikarya, contained gold-labeled secretory granules in the magnocellular paraventricular nucleus of rats. The perikarya were also synapsed with unlabeled nerve fibers. It is concluded that SP plays a role as an axosomatic neurotransmitter in diverse synaptic controls of vasopressinergic neurons.

Animals↗
PubMed1986

Immunoelectron microscopic observations of hypothalamic TRH-containing neurons in rats.

Immunoreactive TRH-containing neurons and their synaptic associations were studied electron microscopically in the paraventricular nucleus (PVN) and dorsomedial nucleus (DMH) of the rat hypothalamus. In propylthiouracil (PTU)-treated rats, the immunoreactive cell bodies in the PVN appeared to be activated, showing a hypertrophic perikaryon, well developed Golgi bodies and numerous secretory granules. No such alterations were evident in the TRH neurons in the DMH. These findings suggest that the PVN-TRH neurons are involved in the hypothalamic-hypophysial-thyroid axis. Further, it was shown that unlabeled nerve terminals containing small and large clear vesicles make synaptic contacts with the TRH perikarya in the PVN. Thus it is likely that PVN-TRH neurons are regulated both by thyroid hormones and by other neuronal signals. In the DMH, unlabeled nerve terminals containing small and large clear vesicles, and immunoreactive terminals form synapses with TRH neurons. Thus the DMH-TRH neurons may be under dual neuronal control. It was further noted that in the DMH and PVN, TRH nerve terminals make synaptic contacts with other unlabeled neurons. It is evident that TRH acts as a neurotransmitter or neuromodulator, although the origin of TRH terminals should be elucidated.

Animals↗
PubMed1985

Hypothalamic thyrotropin-releasing hormone (TRH)-containing neurons involved in the hypothalamic-hypophysial-thyroid axis. Light microscopic immunohistochemistry.

The localization of neurons containing immunoreactive thyrotropin-releasing hormone (TRH) was examined in the hypothalamus of intact, propylthiouracil (PTU)-treated, and colchicine-treated adult rats. In intact animals, immunoreactive TRH neurons were occasionally found in the paraventricular and dorsomedial nuclei, and in the anterior and lateral hypothalamic areas. In PTU-treated animals, the cellular appearance of the hypothalamus with the exception of the paraventricular nucleus was almost similar to that of intact animals. In the paraventricular nucleus, only the cells localized in the periventricular and medial parvocellular subdivisions significantly increased in number and became hypertrophic in comparison with intact animals. The distribution of immunoreactive fibers in the hypothalamus was almost equal among the 3 animal groups with the exception of that in the median eminence, in which the fibers were most densely concentrated in intact animals, and most sparse in PTU-treated rats. The fibers projecting into the median eminence were distinguished into the periventricular and lateral pathways, which are derived from the neurons in the periventricular and medial parvocellular subdivisions of the paraventricular nucleus, respectively. Thus, among immunoreactive TRH neurons in the hypothalamus, only those in the periventricular and medial parvocellular subdivisions of the paraventricular nucleus may be involved in the hypothalamic-hypophysial-thyroid axis.

Animals↗
PubMed1985

Ultrastructural evidence for the existence of the distal retinal pigment light-adapting hormone in the sinus gland of the prawn Palaemon paucidens.

The position of the distal retinal pigments was measured in the eyes of Palaemon which had been exposed to various light intensities (0-2000 lux) for periods up to 7 days. Electron microscopical observations of sinus glands from these animals revealed that long-term illumination (1000 lux, 7 days) resulted in almost complete degranulation of the Type 2 axon terminals, reflecting intense discharge of the granules. On the other hand, the Type 2 terminals of dark-adapted prawns showed no signs of hormone release, such as exocytosis. The results indicate that the light-adapting hormone is liberated from Type 2 terminals. The Type C cell somata in the medulla terminalis, containing granules of similar size to those in the Type 2 terminals, may be the site of synthesis of this hormone.

Animals↗
PubMed1985

Freeze-drying technique in electron microscopic immunohistochemistry.

Postembedding immunocytochemical labeling was performed on sections of rat neurohypophysis prepared by either freeze-drying, vapor fixation and Spurr resin embedding, or conventional aqueous fixation and Spurr resin embedding. Arginine vasopressin (AVP) and oxytocin (OXT) were immunolabeled with protein A-gold-anti-AVP and protein A-gold-anti-OXT complexes, respectively. The freeze-drying procedure (FD) resulted in excellent preservation of ultrastructure and greater antigenicity than the conventional procedure (Con). More gold particles were seen over secretory granules in FD sections than in Con sections. In addition, in FD sections, the gold label was restricted to secretory granules while in Con sections, both the granules and the extragranular axoplasm exhibited label. The two antigens in FD sections could be labeled simultaneously with protein A-small gold particle-anti-OXT complex and protein A-large gold particles-anti-AVP complex. In this way the two antigens were seen to be present in secretory granules within different axon terminals. Thus FD preparations should be useful for demonstrating the presence of multiple antigens in the same granules of nerve terminals.

Animals↗
PubMed1985

Intragranular colocalization of immunoreactive methionine-enkephalin and oxytocin within the nerve terminals in the posterior pituitary.

To determine differential tissue antigens in the same section immunocytochemically using the electron microscope, the neurohypophysis was examined following the application of a freeze-drying tissue preparation and staining with the protein A-colloidal gold-antibody complex method (Hisano S, Adachi T, Daikoku S: J Histochem Cytochem 32:705, 1984). At the light microscopic level, colocalized immunostaining for methionine-enkephalin (ENK) and oxytocin (OXT) was found in the rat neurohypophysis under different physiological states. Small pieces of the neurohypophysial tissue were frozen and dried. The dried tissue was fixed with paraformaldehyde vapor and embedded. The ultrathin sections were stained with the antibody for ENK coupled with protein A-small colloidal gold, and antibody for OXT or vasopressin (VP) conjugated with protein A-large colloidal gold. The ultrastructures of the nerve terminals were well preserved and showed many membrane-limited secretory granules. It was possible to identify both OXT- and VP-containing nerve terminals as their secretory granules were differentially labeled with protein A-colloidal gold anti-OXT or anti-VP complex, respectively. The secretory granules, which were labeled with large gold particles for OXT, also carry small gold particles. It is evident that ENK coexists with OXT in the same granules.

Animals↗
PubMed1984

Synaptic regulation of hypothalamic neurons containing ACTH by substance P.

Synaptic connections between substance P (SP)- and ACTH-containing neurons in the rat arcuate nucleus were studied by a technique of combined pre- and postembedding immunohistochemical staining. The results showed that immunoreactive (ir) SP fiber terminals form synapses with ir ACTH cell bodies. This strongly suggests that the activity of ACTH neurons is under neuronal regulation by SP neurons.

Adrenocorticotropic Hormone↗
PubMed1984

Hypothalamic substance P-containing neurons. Sex-dependent topographical differences and ultrastructural transformations associated with stages of the estrous cycle.

Immunoreactive substance P (ir SP)-containing neurons were examined in rat hypothalamus. In untreated males, few if any ir perikarya were found in the arcuate nucleus, but after intraventricular colchicine administration, many appeared not only in the arcuate nucleus but also in the premammillary region, posterior hypothalamic, ventromedial, dorsomedial, subthalamic and paraventricular nuclei, and zona incerta. This was also the case in females treated with colchicine on the second day of diestrus. In untreated females, perikarya were seen only in the arcuate nucleus, varying in number and ultrastructure during the estrous cycle and being maximal in number in proestrus and estrus. The perikarya possessed well-developed Golgi bodies and lamellar bodies composed of many closely apposed cisternae of endoplasmic reticulum in proestrus, and showed stacks of two or three cisternae of endoplasmic reticulum as well as lysosomes in estrus. In diestrus, the perikarya had only a few granulated vesicles and fragmental cisternae of endoplasmic reticulum. In the perikarya of colchicine-treated males, many granulated vesicles and lysosomal bodies were noted. These findings suggest that, among the widely distributed SP neurons in the hypothalamus, some in the arcuate nucleus are involved in the hypothalamic-hypophysial-gonadal axis.

Animals↗
PubMed1984

Morphological evidence for synaptic junctions between substance P-containing neurons in the arcuate nucleus of the rat.

The presence of synaptic junctions between substance P-containing neurons (SP neurons) was shown in the hypothalamic arcuate nucleus of rats by pre-embedding electron microscopic immunohistochemistry. The immunoreactive perikarya were synapsed by immunoreactive fiber terminals as well as immunonegative fiber terminals. The functional implication of the synapses between SP neurons is discussed in relation to autoregulatory mechanisms of the neurons.

Adrenocorticotropic Hormone↗
PubMed1984

Ontogenetic appearance of somatostatin-containing nerve terminals in the median eminence of rats.

The development of immunoreactive (ir) somatostatin-containing nerve terminals in the rat median eminence (ME) has been examined electron-microscopically. Nerve fibers containing ir particles scattered throughout the axoplasm are first seen in the external layer of the ME on day 18.5 of gestation, and, on day 21.5 appear to terminate on the basement membrane of the perivascular space of the portal vessels. After birth, the fiber terminals contain several membrane-limited granules, which are labeled with ir PAP particles. Ultrathin, Epon-embedded sections of ME, treated by the protein A gold-labeling method for somatostatin, demonstrate positively labeled granules in the nerve fibers in the postnatal ME, but in the prenatal tissue, no specific gold-labeling is found. These findings show that, in the external layer of the ME, somatostatin storing occurs in the granules in the axonal terminals after birth.

Aging↗
PubMed1984

Immunolabeling of adenohypophysial cells with protein A-colloidal gold--antibody complex for electron microscopy: use of the freeze-substitution technique in tissue preparation.

The value of the freeze-substitution (FS) method for preparing tissues for electron microscopic immunohistochemistry was studied by comparing anterior pituitary cells prepared by this method and by a conventional method. Ultrathin sections of tissues embedded in Epon were subjected to immunostaining. The antigens adrenocorticotropin (ACTH) and prolactin (PRL) in a single ultrathin section were demonstrated by a simple double-labeling technique using a protein A-colloidal gold-antibody (pAG-Ab) complex. The preservation of cellular ultrastructure was superior in preparations obtained by FS. Gold-labeling was seen over secretory granules, and in ACTH cells also over the cytoplasmic matrix. The labeling was more intense in preparations obtained by FS, judging from the numbers of gold particles. In the double-labeling procedure, in which the pA-small colloidal gold-anti-PRL complex and pA-large colloidal gold-anti-ACTH complex were applied sequentially to sections, no cross-labeling with small and large gold particles was observed. It is concluded that if the antisera are sufficiently specific, the use of FS and the pAG-Ab complex is very effective in peptide immunohistochemistry. However, in the double-labeling procedure it is essential that the Fc-binding sites of pAG are saturated by the use of excess amounts of antibodies.

Animals↗
PubMed1983

Substance P-like immunoreactive neurons in the tuberoinfundibular area of rat hypothalamus. Light and electron microscopy.

Immunoreactive substance P (ir SP) neurons were examined with special reference to their links with other neurons and blood vessels in the tuberoinfundibular hypothalamic area of normal and colchicine-treated male rats. On intraventricular administration of colchicine, ir SP neuronal cell bodies appeared in both the arcuate nucleus and the ventral portion of the ventromedial nucleus. These ir fibers were seen in the nuclei of untreated animals closely surrounding ir methionine-enkephalin and ACTH cell bodies, suggesting the presence of synaptic junctions. Electron microscopic examination of the arcuate nucleus stained with anti-SP serum showed synapses of ir SP fiber terminals on unlabeled neuronal cell bodies and fibers, some of which might be methionine-enkephalin and ACTH neurons. The ir fiber terminals contained numerous small clear and/or cored vesicles and a few large cored vesicles. Fiber terminals with the same ultrastructural characteristics were seen protruding into the pericapillary space in the external and subependymal layers of the median eminence. The possible role of the SP neurons in the tuberoinfundibular area is discussed.

Animals↗
PubMed1983

Electronmicroscopic study of somatostatin-containing neurons in rat arcuate nucleus with special reference to neuronal regulation.

After an intraventricular administration of colchicine, the arcuate nucleus of rat hypothalamus was examined light and electron microscopically by pre-embedding immunohistochemistry for somatostatin. The arcuate nucleus exhibited numerous immunoreactive cell bodies and dense networks of immunoreactive fibers. The fibers appeared to surround immunonegative cell bodies. The immunoreactive cell bodies were multipolar in shape and projected immunoreactive processes to some extent. The immunoreactive cell bodies and fibers received synaptic contacts by immunonegative fiber terminals containing a large number of synaptic clear vesicles. Similarly, immunoreactive somatostatin fibers appeared to terminate upon other immunonegative cell bodies and fibers. The immunoreactive presynaptic terminals contain several labeled granules and numerous synaptic vesicles. In close proximity to these immunolabeled terminals, non-labeled presynaptic terminals were also observed upon the immunonegative cell bodies and fibers. This suggests that in the arcuate nucleus neurons regulated by somatostatin neurons are also under the control of other types of neurons.

Animals↗
PubMed1983

Ontogenetic studies on the topographical heterogeneity of somatostatin-containing neurons in rat hypothalamus.

The ontogeny of the somatostatin-containing neuron system was investigated by light-microscopic immunohistochemistry. During development, immunoreactive somatostatin-containing neurons arise from three discrete regions of the neuroepithelium of the third ventricle and show a chronological difference. The neurons are first evident within the third ventricle floor on day 12.5 of gestation; they move thereafter to the arcuate nucleus. The second generation occurs in the dorsal region of the arcuate nucleus during days 17.5-19.5; these neurons migrate sequentially into the arcuate-ventromedial nuclear region. The third generation is recognized in the neuroepithelial cell layer of the rostral hypothalamus on day 17.5 of gestation; these cells move to the periventricular area. This latter generation is most prominent during days 3-6 after birth, and some of the cells are seen sporadically even up to day 20. The first two generations give rise to the somatostatin neuron system in the arcuate-ventromedial nuclear region, while the latter gives rise to that in the rostral periventricular region in the adult rat hypothalamus.

Animals↗
PubMed1983

Current status of benign biliary disorders in Japan and accuracy rates of preoperative diagnoses. Collective review of 14,654 patients.

Data on 14,654 patients preoperatively diagnosed for benign lesions who had undergone surgical treatment during a 2 year period (April 1979 to March 1981) were obtained from 145 institutions. A total of 18,891 biliary disorders were confirmed and classified into 18 groups: stones in the gallbladder, 12,272 patients (83.7 percent of all patients); stones in the extrahepatic bile duct, 3,605 patients (24.6 percent); stones in the intrahepatic bile duct, 570 patients (3.9 percent); acalculous cholecystitis, 463 patients (3.2 percent); idiopathic dilatation of bile ducts, 375 patients (2.6 percent); stenosing papillitis, 274 patients (1.9 percent); benign stricture of bile ducts, 133 patients (0.9 percent); and others. Malignant tumors were found in 243 patients, of whom 132 (54.3 percent) were not expected to have gallbladder cancer. Accuracy rates for preoperative diagnoses in the patients with gallstones of the intrahepatic or extrahepatic bile ducts or the gallbladder, idiopathic dilatation of the bile ducts, benign stricture of the bile ducts, or benign stenosis of the papilla of Vater were higher than 90 percent. However, the false-negative rates for these six disorders, except gallstones of the gallbladder, were higher than 16 percent. Therefore, despite advances in diagnostic procedures before surgery, intraoperative examinations remain indispensable for determining the most effective approach to surgical repair.

Adult↗