Recent histochemical works provided several lines of evidence showing discrepancies between localizations of neurotransmitters and their receptors. Therefore, re-consideration of the discrepancies from the receptor side seems crucial to understand exact chemical neuro-circuit. In this article, some examples of unexpected localization of neurotransmitter receptors were demonstrated. The following subjects were focused on in particular. (1) Localization of some glutamate receptors in rat pituitary gland. (2) Localization of glutamate receptors in the autonomic ganglia. (3) Mismatching of substance P and its receptor NK-1 localizations in the strio-nigral system.

View full abstract

Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma of adult life. Its clinicopathological entity, however, is not completely established because of its uncertain histogenesis. In this review, the histogenesis of MFH is discussed through an overview of the concept of macrophage ontogeny. Our recent multiparametric studies indicate that MFH is a tumor of mesenchymal cells with fibroblastic differentiation. Histiocyte-like cells in the tumor are considered to be not neoplastic component but infiltrated macrophages. Because this tumor is not one of the histocytes or macrophages, the term “malignant fibrous histiocytoma” is inappropriate. Instead, this tumor should be renamed as a special type of mesenchymal cell tumor differentiating toward fibroblasts and producing monocyte chemoattractants and macrophage differentiation factors.

View full abstract

The c-kit receptor tyrosine kinase and its ligand, stem cell factor (SCF), play an important role for regulation of mast cells. The symptoms of mouse mutants at either c-kit or SCF gene apparently show the physiological significance of the signal through the c-kit receptor tyrosine kinase. The number of mast cells in the skin of various murine c-kit mutants may be explained by the type and severity of the mutations. All mutations reported in mice and rats are loss-of-function mutations, but we recently found a gain-of-function mutation of c-kit in mastocytoma cell lines. In these mastocytoma cell lines, the c-kit receptor tyrosine kinase is activated constitutively without binding of SCF. The c-kit receptor tyrosine kinase appears to be important not only for development of mast cells but also for neoplastic transformation of mast cells.

View full abstract

The discrimination of nuclear phenotypes of Feulgen-stained ras-transformed and nontransformed NIH 3T3 cells previously determined by image analysis using the scanning microspectrophotometry system, was investigated with the video system. A reasonable matching of the Feulgen-DNA values obtained with the two methods was demonstrated. Chromatin texture evaluated on the basis of the scatter diagram relating condensed chromatin relative areas vs. an average absorption ratio could also be assessed with the video system. The video image analysis system was effective in distinguishing nuclear phenotypes which differ in chromatin supraorganization in ras-transformed as well as in nontransformed NIH 3T3 cells, in distinguishing phenotypes not visually discernible from each other (transformed vs. nontransformed cells) and in discriminating among the cell lines used.

View full abstract

The distribution of epidermal growth factor (EGF) binding sites in the mouse digestive system was investigated by in vivo whole-body autoradiography. Male mice were injected intravenously with ¹²⁵I-EGF in both the absence and the presence of excess unlabeled EGF. The animals were perfused and subjected to autoradiographic procedures 3, 5, 15, and 30min after injection. Our study provides the first quantitative data on the binding levels of digestive system tissues under in vivo conditions with intact experimental mice.
Specific EGF binding was observed in the liver, pancreas, stomach, and intestinal mucosae at 3, 5, and 15min post-injection, but at 30 minutes the bindings were not lowered by the presence of excess unlabeled EGF. Very high specific EGF binding was noted in the liver, where distribution of the binding sites was heterogeneous, and the density of the binding was higher around the branches of the portal vein than around the central vein. In the stomach, relatively high specific binding was seen in the glandular part, but the non-glandular portion showed no significant binding. There was low specific binding in the pancreas and distribution of that binding was homogeneous according to macroscopic observation. Low specific binding was observed in the intestinal tract from duodenum to rectum, and level of the binding was quite similar throughout the tract. The esophagus evinced no substantial EGF binding. Submandibular and sublingual glands showed relatively high radioactivity during the experimental period, but most of it was nonspecific in nature.

View full abstract

The aim of the present study was to determine if normal liver cell kinetics can be evaluated using bromodeoxyuridene (BrdU) as the label. BrdU was injected intraperitoneally into 10 male adult rats, 5 were sacrified after 1hr, and the remainder after 30 days. The livers were fixed in 70% ethanol, embedded in paraffin and histological slides were prepared. The labelled nuclei were revealed using indirect immunoperoxidase staining and easily counted by light microscopy. One hr after labelling, labelled hepatocytes and littoral cells were detected within 164±12.3μm and 161±13μm respectively from the portal tract rim. After 30 days, both cell types reached the respective distances of 290±14.6μm and 294±17.7μm. Their respective displacement velocities were 4.2μm/d and 4.3μm/d. These results were identical to those we obtained using tritiated thymidine. This laboratory method provides a useful and simpler alternative method to tritiated thymidine.

View full abstract

Samples of carotid bodies from control and reserpinized rabbits were incubated in a sodium chromate and potassium dichromate buffer after primary glutaraldehyde fixation. Such a cytochemical staining method could show that the reserpine treatment resulted in a decrease in the electron density of the densecored vesicles to a different degree in different subtypes of Type I cells. The decrease was moderate in subtype B cells, obvious in subtype C cells, and invisible in subtype A cells. The present work offered a morphofunctional evidence for the existence of subtypes of Type I cells, and gave a hint that the different subtype cells may store different catecholamines.

View full abstract

The synovial lining layer consists of two cell types ultrastructurally. It is said that the function of type A cell is phagocytosis and one of type B cell is secretion of synovial fluid, but the details are still obscure. For a better understanding of these mechanisms, the localizations of five phosphatase activities, i.e. Mg²⁺-activated adenosine triphosphatase (Mg²⁺-ATPase), Ca²⁺ -activated adenosine triphosphatase (Ca²⁺ -ATPase), ouabain-sensitive, potassium-dependent adenosine triphosphatase (Na⁺, K⁺ -ATPase), acid phosphatase (ACPase) and thiamine pyrophosphatase (TPPase) activities, were studied ultracytochemically on the rat knee joints. Type A cell had Mg²⁺ -ATPase and Ca²⁺ -ATPase activities on the plasma membrane, especially on the filopodia. Type B cell had these activities at the pinocytotic vesicles. Na⁺, K⁺ -ATPase, ACPase, TPPase activities were found at the Golgi apparatus of type B cell. ATPase on the plasma membrane is the enzyme which supplies the energy needed at active transport or cytosis. So the localizations of these enzyme activities may raise the possibility that both type A and B cells might have mechanisms governing the intraarticular homeostasis of the synovial fluid. And on type B cell, basic data were given about the function of the Golgi apparatus. Furthermore in the synovial lining layer, type A and B cells will be distinguishable not only structurally but also cytochemically.

View full abstract

The uptake of ³H-leucine by peri- and tele-insular acinar cells of the pancreas was analyzed quantitatively 60 min after the intraperitoneal injection of ³H-leucine in normal and streptozotocin-diabetic mice. A large tissue sample was analyzed and the grain density was counted with a color image analyzer equipped with a computer. The radioactivity was expressed as number of silver grains per acinar cell as well as per unit area of acinar tissue. In normal mice, the radioactivity in peri-insular acinar cells was 43% greater than in tele-insular acinar cells. The intercalated ducts associated with the former also showed a larger number of silver grains. In streptozotocin-diabetic mice, the uptake of ³H-leucine in peri- and tele-insular acinar cells was almost similar. The estimate of mean acinar cell profile area was 30% larger in the peri-insular acini of normal mice, while no difference was observed between the estimates of peri- and tele-insular acinar cells of diabetic mice.
These results confirm previous reports that the B cell serection plays a certain role in the protein synthesis of pancreatic acinar cells, especially for the cells of peri-insular acini.

View full abstract

The effect of a synthetic steroidal anti-androgen, TZP-4238, on steroid-induced rat dorsolateral prostatic hyperplasia was investigated. Male Sprague-Dawley rats were divided into five experimental groups. Group 1 consisted of intact controls. The other animals were castrated. The castrated animals were treated for seven weeks with 1) testosterone 1mg/animal plus 17β-estradiol (E₂) 10μg/animal (Group 2), 2) testosterone plus E₂ plus TZP-4238 2mg/kg (Group 3), 3) testosterone plus E₂ plus TZP-4238 8mg/kg (Group 4) and 4) testosterone plus E₂ plus Tween 80 (Group 5) instead of TZP-4238. TZP-4238 was administered orally for four weeks after three weeks of treatment with testosterone plus E₂. In groups 2 and 5, glandular hyperplasia of the dorsolateral prostate was clearly observed, and the fibro-muscular stromal proliferation was also noted. The glandular epithelial cells showed uniformly intense nuclear immunostaining for androgen receptors (AR). Furthermore, AR was also localized in the nuclei of the proliferated fibromuscular cells. In contrast, combined treatment with TZP-4238 (Groups 3 and 4) produced inhibition of the glandular hyperplasia. Furthermore, nuclear immunostaining of AR of both epithelial and stromal cells was remarkably decreased. These results indicate that the uptake of testosterone and/or its androgenic effect on the dorsolateral prostate may be suppressed by TZP-4238. Furthermore, the decreased AR immunostaining may be explained by the decrease in number of AR and/or antibody binding site for AR.

View full abstract

We describe a rapid fluorescent in situ hybridization (FISH) procedure with X and Y chromosome-specific DNA probes for sexing human embryos and fetuses using paraffin-embedded tissues. The effects of various fixatives and pretreatment conditions on FISH efficiency were examined in different embryonic and fetal tissues. Fluorescent hybridization signals were identified in tissues which had been fixed in 4% paraformaldehyde (PFA) or 10% formalin but not in Bouin-fixed tissues. The preservation in 4% PFA at 4°C yielded better FISH results than that in 10% formalin at room temperature. Another critical factor for visualization of fluorescent hybridization signals in paraffin sections was the duration of proteinase K digestion. Optimal digestion visualized hybridization signals more clearly probably because it increased the accessibility of DNA probes into nuclear DNA in paraffin sections. We have succeeded in shortening the hybridization time significantly and eliminating an immunocytochemical step for amplifying hybridization signals, and it has become possible to sex human conceptuses in paraffin sections within 5 hr. This FISH technique should be useful to sex fixed human embryos and fetuses retrospectively and to diagnose sex chromosome aneuploidies using fixed tissues.

View full abstract