Pre- and postnatal developmental changes in hypothalamic and pituitary content of alpha-melanocyte-stimulating hormone and somatostatin in the rat

The developmental pattern of hypothalamic and pituitary somatostatin and alpha-melanocyte-stimulating hormone (alpha-MSH) was studied in the rat by radioimmunoassay (RIA). Prenatally hypothalamic somatostatin was low and the first increase in content occurred on day 5 of the postnatal period. Pituitary somatostatin was undetectable prenatally and was first detected on day 6 postnatally. Pituitary somatostatin showed the same development pattern as hypothalamic somatostatin. Whole pituitaries were analyzed from the fetuses and neonates. Analysis of anterior and posterior lobes from adults revealed that all the somatostatin was in the posterior lobe. Therefore, it is believed that the somatostatin found in the glands of the younger animals was in the neural lobe. alpha-MSH was detected in the fetal hypothalamus as early as day 16, with a marked increase occurring on day 19 prenatally and a further increase on day 10 postnatally. Pituitary alpha-MSH content, readily detectable on the first day examined, i.e. day 16 of the fetal period, increased throughout development. The effect of alpha-MSH on the release of growth hormone in vitro from pituitaries of rats of various ages was tested. alpha-MSH had no effect on growth hormone release.

Concerning the presence of an insulin-related peptide in the human brain: an immunohistochemical reinvestigation by use of monoclonal insulin antibodies

The immunohistochemical localization of insulin/insulin-like immunoreactivity in different regions of the human brain was reevaluated by use of monoclonal antibodies against insulin. The data obtained support our earlier findings that cerebral insulin is present in nerve cells of several brain areas.

Phorbol ester receptors: autoradiographic identification in the developing rat

Autoradiography with 3H-labeled phorbol dibutyrate was used for the light microscopic detection of phorbol ester receptors in rat fetuses. In 15- and 18-day fetuses, as well as in adult rats, receptors were found to be concentrated in the central nervous system. The localization of receptors in the ventral marginal zone of the fetal neural tube, the lens of the eye, and other sites suggests a role for phorbol ester receptors in cellular process extension and cell-cell interaction.

Human gastric cancer-associated antigens and carcinoembryonic antigen detected by monoclonal antibodies

The serologic and molecular characterization of four monoclonal antibodies to human gastric cancer cells and to CEA were described and the immunohistologic patterns of reactions with freshly obtained gastrointestinal tissues were examined. Monoclonal antibody YK004, which was secreted by the hybridoma constructed with the gastric carcinoma cell line KATO III, reacted with an antigenic determinant preferentially expressed on human gastric and colonic carcinoma cells, but it failed to bind any nonmalignant tissues tested except the stomach. Although this antibody reacted with fetal digestive tract tissues, it failed to immunoprecipitate CEA. Monoclonal antibodies YK013 and YK024 prepared in the same manner by immunizing with the gastric carcinoma cell line KATO III reacted with antigenic determinants on CEA, but not on NCA or NCA2. The antigenic profiles recognized by these two antibodies were found to be identical by sequential immunoprecipitation experiments. However, the antigenic determinant recognized by antibody YK013 may be different from that recognized by antibody YK024, since the immunohistologic reactivity patterns in carcinoma tissue sections were clearly different. Monoclonal antibody AS001, which was secreted by the hybridomas constructed with purified CEA as immunogen, immunoprecipitated CEA molecule with a single antigenic structure of 200 Kd, which was different from the antigenic profile detected by two other monoclonal antibodies, YK013 and YK024. The unique distribution of the antigenic determinants recognized by our monoclonal antibodies on cancerous tissues suggests that antibodies might be able to detect the unique determinants of the circulating CEA molecule or CEA-related molecules in the serum of cancer patients.

Thallium determinations in fetal tissues and maternal brain and kidney

The transfer of T1+ cations through the placental barrier of pregnant mice and rats was studied by comparing the thallium concentrations in the maternal brain and kidney and those in fetal tissue at times of 10 min to 50 h after dosage of the animals with 10 mg/kg body wt. T1(2)SO4. The quantitative determinations were performed with field desorption mass spectrometry after dilution of the homogenised tissue samples with enriched stable isotopes of thallium. The total sample quantity required for one complete assay is 1-3 micrograms, the analysis time for one determination about 30 min.

Transplacental permeability of 125I-sfericase in mice

125I-sfericase was administered intravenously into the tail vein of mice on day 20 of gestation at a dose of 1 mg/kg as sfericase. The penetrability of sfericase into the placenta, radioactivity levels, and precipitable high molecular 125I treated with TCA were measured in maternal blood and plasma and fetal homogenates collected at 20 and 90 min after i.v. injection. The radioactivity level in fetuses was considerably lower than that in dams at 20 min but almost comparable to that of dams at 90 min, indicating considerably good penetrability of the radioactivity into the placenta. However, after treatment with TCA, the content of high molecular 125I in fetuses was considerably lower than that in maternal blood. These results suggested that high molecular 125I degraded into a low molecular fraction while passing the placenta to reach the fetus.

The distribution of plasma proteins during early embryonic development in the sheep

The distribution of the five plasma proteins that are quantitatively most important during development in the sheep has been studied in embryos of 15 to 21 days gestation. The three primary embryonic layers and tissues that differentiate from them were tested for the presence of alpha-fetoprotein (AFP), fetuin, albumin, transferrin and alpha 1-antitrypsin using the indirect immunoperoxidase method. Fetuin was the most prominent of these proteins particularly in the developing central nervous system. Fetuin and transferrin appeared early in the differentiating mesoderm and, with albumin and AFP, were detected in tissues originating from all three layers during the course of development. alpha 1-Antitrypsin appeared to have a limited distribution. All five plasma proteins were detected before the establishment of a circulatory system. It is suggested that their appearance in embryonic tissue is related to its stage of development and that they play an important part in early differentiation.

Distribution of CL glycoprotein in tissues: an immunohistochemical study

CL glycoprotein is a collagen-like glycoprotein which we have recently isolated from rapidly growing fetal bovine, elastin-rich tissues. This protein has a molecular weight of approximately 140,000 daltons, contains hydroxyproline and hydroxylysine and is digested by highly purified collagenase to yield three large polypeptides. A specific antibody has been developed against this protein and has been used for immunofluorescence microscopy to study the distribution of CL glycoprotein in a range of tissues. It has been shown that the antibody localized in the intercellular matrix of nuchal ligament and aorta, of the non-elastic Achilles tendon and in complex tissues such as kidney, lung, skin and spleen. The antibody also localized to the surface of aortic smooth muscle cells-presumably to the basement membrane, but did not bind to other basement membranes, including the vascular subendothelial basement membrane. The pattern of distribution was similar in adult bovine tissues. As this antibody showed no avidity for elastic tissue elements, it is most unlikely that CL glycoprotein is a constituent of elastin-associated microfibrils. When the pattern of the CL glycoprotein distribution within the tissues was studied, it was found that, apart from its concentration around vascular smooth muscle cells, CL glycoprotein exhibited considerable overlap in distribution with the interstitial collagens. On the basis of these observations and having regard to its biochemical characteristics, it is proposed that CL glycoprotein has a structural role inter-linking interstitial components to one another and to vascular smooth muscle cells.

Expression of glial fibrillary acidic protein, actin, fibronectin and factor VIII antigen in human astrocytomas

Frozen sections and cell cultures of 50 human astrocytomas, fetal and adult human brain were examined for immunofluorescence reactivity with antisera to glial fibrillary acidic protein (GFAP), actin, fibronectin and factor VIII antigen. In frozen tissue sections GFAP expression was restricted to normal and neoplastic astrocytes while fibronectin and factor VIII antigen were localized to blood vessels. In primary cell culture, 80-100% neoplastic astrocytes expressed GFAP but not fibronectin or factor VIII antigen while actin was present as diffuse cytoplasmic staining of the cell body and cell processes. By the 5th-6th passage in vitro, GFAP immunoreactivity was lost while fibronectin and actin cables were prominently expressed. Factor VIII antigen remained negative throughout serial subculture. In double fluorochrome experiments, GFAP positive cells did not express fibronectin or actin cables, while GFAP negative cells expressed fibronectin and had prominent actin cables. Our results suggest a change in population of astrocytoma cells with increasing passage in vitro, reflecting either an overgrowth of tumour glioblasts or dedifferentiation of tumour astrocytes.

Thyroxine, 3,5,3' -triiodothyronine and 3,3', 5' -triiodothyronine in human amniotic fluid: relationships between concentrations and turnover

We have made estimates of the possible contributions of various routes of entry and disposal to the turnover of thyroxine (T4), 3,5,3'-triiodothyronine (T3) and 3,3',5'-triiodothyronine (reverse T3, rT3) in human amniotic fluid (AF). Our calculations suggest that, in normal pregnancy, AF T4 and T3 are derived mainly from the maternal circulation, and that their concentrations depend very largely on binding-protein concentrations. The majority of AF rT3 is unlikely to enter the amniotic sac directly from the maternal circulation, or from the fetal circulation by passive diffusion or fetal urinary excretion; however, our calculations are consistent with the hypothesis it is derived largely from inner-ring deiodination of T4 in the fetal membranes. We propose that the molar ratio of one AF iodothyronine to another may yield more information about fetal thyroid status than the total concentration of any single iodothyronine.

Studies of the uptake and distribution of inulin and alpha-aminoisobutyric acid after intraamniotic injection in the guinea pig

Pregnant guinea pigs were given intraamniotic injection of 14C-alpha-aminoisobutyric acid and 3H-inulin. Both substances were taken up by the fetus in different concentrations. High levels of alpha-amino-isobutyric acid were found in the placenta, liver, and serum. Inulin on the other hand, being a macro-molecule distributed by diffusion in the extracellular space, was found in high concentrations in the small intestine and in the placenta. Thus the main pathway for transferring nutrient substances from the amniotic fluid to the fetus would seem to be the gastro-intestinal tract. Thus supplementary nutrition of the fetus by the intraamniotic injection of nutrients is a possibility.

Cellular localization of chorionic gonadotropin in human fetal kidney and liver

Earlier, we reported that second trimester human fetal kidney and, to a much lesser extent, human fetal liver were capable of synthesizing and secreting the beta-subunit of hCG. Recently, we also have shown that these tissues, likewise, synthesize and secrete the alpha-subunit of hCG. The hCG produced is biologically active. To determine the cellular localization of these peptides, immunocytochemical studies were performed on human fetal tissues using antibodies against beta hCG, alpha hCG, and the intact hormone. Placental syncytiotrophoblast served as an immunopositive control. In the human fetal kidney, the ascending (thick) limb of the loop of Henle, distal convoluted tubule, and occasional cells in the collecting ducts were distinctly immunopositive for both beta hCG and the alpha-subunit. Small amounts of light positive staining occurred in only a few hepatocytes. Placental syncytiotrophoblast was routinely positive for both subunits, but fetal lung and striated muscle were negative. These immunocytochemical results indicate that immunoreactive beta hCG as well as the alpha-subunit are present in placental syncytiotrophoblast, in the distal renal nephron, and in a limited population of hepatocytes. The qualitative number and intensity of immunopositive cells closely correlate with the quantitative amounts of their hCG subunit synthesis. Taken together with our previous biosynthetic data, the immunocytochemical localization reported here indicates the probable cellular sites of alpha- and beta hCG synthesis in these tissues. The presence of comparable alpha- and beta-subunit staining in identical cell populations suggests that both hCG subunits and, therefore, perhaps intact hCG are produced at these same cellular sites during fetal life.

Production and molecular size heterogeneity of immunoreactive gastrin-releasing peptide in fetal and adult lungs and primary lung tumors

Gastrin-releasing peptide (GRP) is known to be a bombesin-like peptide present in mammalian tissues. Using GRP radioimmunoassay specific for carboxyl-terminal portion, the immunoreactive GRP (IR-GRP) content of 5 fetal lungs, 38 adult lungs, and 131 primary lung tumors was determined. All fetal lung extracts contained IR-GRP ranging from 31 to 140 ng/g, wet weight. IR-GRP was present in 7 to 21% of normal adult lungs and lung carcinomas other than small-cell carcinoma; the amount was not very large except in two cases of adenocarcinoma, in which 110 and 140 ng/g of IR-GRP were detected. In the case of small-cell carcinoma, IR-GRP was found in 23 of the 31 cases examined (74%), and nine (29%) of these contained large amounts of IR-GRP (100 to 14,000 ng/g). As for carcinoid tumors, IR-GRP was found in five of the 12 cases examined (42%), and large amounts of IR-GRP were detected in two cases (5,100 to 130,000 ng/g). Immunohistochemically, IR-GRP was found in the neuroendocrine cells of fetal lungs and in the tumor cells of primary lung tumors. When these tissue extracts were examined by bombesin radioimmunoassay that recognizes bombesin but not GRP, they did not contain immunoreactive bombesin, suggesting that IR-GRP in these tissues is more similar to GRP than to bombesin. Sephadex G-50 gel filtration always revealed two peaks of IR-GRP in both fetal lungs and IR-GRP-producing tumors. One was eluted at the position corresponding to that of porcine GRP (Peak 1) and the other, at the position just behind that of porcine GRP (14-27) (Peak 2). In the five fetal lungs, Peak 2 comprised more than 83% of the total IR-GRP. In the 12 IR-GRP-producing tumors examined, the ratio of these two peaks differed from case to case. Our data indicate that IR-GRP, which is present in fetal lung, is often produced by primary lung tumors, especially by small-cell carcinoma and carcinoid tumor, with molecular size heterogeneity.

Absence of maternal contamination of chorionic villi used for fetal-gene analysis

Chorionic villi can be obtained by direct transcervical aspiration at 9 to 10 weeks' gestation and used for analysis of fetal DNA. However, for the method to be reliable, there must be no detectable contamination by maternal DNA. To investigate the question of contamination, we compared the DNA of chorionic villi from five fetuses with that obtained from maternal lymphocytes, using the restriction endonuclease Taql and specific DNA probes for a pair of alleles on the X chromosome. The alleles yield fragments of different lengths when digested with Taql (length polymorphism), which can be demonstrated by electrophoresis and hybridization with the radioactive DNA probes. If the pattern obtained with the chorionic DNA is different from that obtained with the maternal DNA, contamination is not present. In two cases the fetal DNA of the chorionic villi was shown to be uncontaminated by maternal tissue. In one of these cases the mother was heterozygous and the fetus was homozygous; in the other the mother was homozygous and the fetus was heterozygous. In three other cases no definitive conclusions could be drawn, because the genotypes of the fetus and mother were identical. We conclude that chorionic villi at 9 to 10 weeks' gestation are a source of fetal DNA that can be used for gene analysis, with no detectable contamination by maternal DNA.

[Immunofluorescence study of various constituents of the eyelids in rats before, during and after their closure]

We have brought the evidence for the presence of type I and III collagens and laminin in cultures of eyelid buds removed just before the onset of their junction. The patterns of distribution of laminin (localized in all basement membranes) and of the type III collagen remain constant during all the culture. Type I collagen is distributed homogeneously in the mesenchyma like type III collagen after the twelfth hour of culture. The rapid stabilization of these three distributions would be associated with the persistence of an epithelial seam limited by intact basement membranes between mesenchymal eyelids from the stage of junction to the later stage of disjunction of the eyelids.

Polychlorinated terphenyls (PCTs) use, levels and biological effects

Polychlorinated terphenyls (PCTs) have almost identical characteristics to high chlorinated PCBs: extremely stable, bioaccumulable and biomagnification through food webs might take place. PCT is especially used in investment casting waxes and as a substitute for PCB. In spite of the limited use until now, PCT has been detected in a great variety of environmental samples such as soil, water, shellfish, fish, seals, birds and terrestrial animals. Furthermore, it has been found in paper products and foodstuffs. PCT residues in human tissues--blood, liver, fat and milk--have been detected in some countries. Animal experiments have shown that long-term toxic effects of PCT are of most importance. PCT has a marked inductive effect on the microsomal enzymes in the liver in vertebrates and may cause liver-damage--including tumours. Disturbance of the hormonal--and immunological--systems have also been reported. The most important ecological hazard of PCT--as well as PCB--is the possible disturbance of the reproduction system of the organisms. Many countries do not regulate the use of PCT. In some countries the use of PCT is regulated to closed systems, but the expansion of usage is under consideration in the EEC.

The combined effect of ultrasonic exposure and protein restriction on maternal and fetal mice

This investigation was undertaken to assess the combined effects of protein restriction and ultrasonic energy exposure during pregnancy on the maternal and fetal mouse. Pregnant female mice were fed diets containing either 18% casein (control diet) or 6% casein (restricted protein diet) during gestation. All animals were subjected to the ultrasonic exposure procedure (actual: 2.5 W/cm2 spatial peak; sham: 0 W/cm2; continuous wave for 20 sec at a frequency of 1 MHz) on day 8 of gestation. On day 18 of gestation, the animals were sacrificed. Products of conception were examined, and chemical analysis were performed on maternal liver, placenta and fetus. Our results suggest that there are possible influences of ultrasonic energy exposure to the mouse fetus and placenta, as indicated by the tendency toward decreases of fetal weight, placental weight, and DNA and RNA contents of both fetus and placenta, especially with restricted protein in the maternal diet during gestation. Protein restriction during pregnancy had an adverse influence on both the maternal organism and her products of conception. The nutritional needs for the fetus were not met at the expense of the maternal organism. Parameters of fetal cellular growth were reduced by gestational protein restriction indicating that there is competition for available nutrients between the fetus under time of stress. Results also show that the trends of fetal and placental growth are in the same general direction suggesting the possible usefulness of human placental tissue as a maker for fetal growth in subsequent population studies.

Reduction by copper supplementation of teratogenic effects of D-penicillamine

Previous experiments from this laboratory demonstrated that oral administration of D-penicillamine (DPA) throughout gestation produced significant teratogenic effects and low copper concentrations in both maternal and fetal tissues in a dose-related manner. To test the hypothesis that the teratogenicity of DPA was due to induced copper deficiency, Sprague-Dawley rats were fed throughout gestation complete, purified diets containing 5 (control), 50, or 100 micrograms/g (supplemental) copper. One-half of the rats in each group received DPA at 0.83% of the diet. On day 21 of gestation, fetuses were removed and examined for gross malformations. Selected maternal and fetal tissues were analyzed for copper, zinc, iron and manganese. Animals fed the drug and supplemental copper had a very low incidence of fetal resorption (4%) and malformation (4%) compared to a high frequency of resorption (23%) and malformation (21%) in drug-fed nonsupplemented animals. There were no consistent differences in tissue iron, zinc or manganese levels among the groups. Tissue copper concentrations were lowest in the drug-fed, nonsupplemented group; those of the group fed DPA and supplemental copper were higher, but did not reach control values. Thus, there was a correlation between tissue copper levels and the frequency of malformations, supporting our hypothesis that DPA teratogenicity is due at least in part to induced copper deficiency.

Body and organ size and composition during late foetal and postnatal development of rat

Development induced deep anatomical changes and tissue composition alterations in the rat. To determine the extent of these changes, the organ weight and size of 19 and 21 day rat foetuses and of 1, 5, 10, 20 and 30 day old Wistar rat pups have been studied and compared with adults. Different tissues showed varying rates of cell and tissue growth as well as tissue cellularity during development. Tail length is not a good index of skeletal growth. Brain growth was much slower from late intrauterine life to adulthood than most other organs. Skin weight increased more than 3-fold between days 19 and 21 of intrauterine life. Striated muscle proportion to body weight remained practically constant throughout all postnatal life studied.

[Gynecological cancer and ferritin--a study on the carcinofetoplacental ferritin]

Serum and tissue ferritins were quantitated by a radioimmunoassay kit (SPAC KIT, Daiichi Radioisotope Lab.) and a diagnostic implication of serum ferritins in patients with gynecological diseases was evaluated. In order to investigate the potential use of tumor marker as a feto-placental antigen (protein), ferritin from ovarian cancer was compared with ferritins from normal adult and feto-placental organs. Serum ferritin levels were significantly higher (p less than 0.01) in patients with ovarian adenocarcinoma, Krukenberg's tumor, cervical squamous cell carcinoma and other malignant diseases than in normal women. Among adult organs the kidney and spleen showed the highest and the heart the lowest ferritin content. The ferritin contents of the kidney and spleen were 78.4 micrograms and 76.2 micrograms/g wet weight, respectively and that of the heart was 5.7 micrograms/g wet weight. The ferritin contents of other adult organs ranged from 10 to 25 micrograms/g wet weight. On the other hand the placenta showed the highest and the heart and stomach the lowest ferritin content among feto-placental organs. The ferritin content of the placenta was 7 micrograms/g wet weight. The ferritin contents of other fetal organs were only half as in the placenta. The ferritin contents of ovarian cancers ranged 6 to 8 micrograms/g wet weight and was almost identical to that of the placenta.

The estimation of elastin in fetal tissues by radioimmunoassay of isodesmosine

A radioimmunoassay was developed for the determination of isodesmosine as the tetraacetyl derivative. Isodesmosine tetraacetate conjugated with bovine albumin was injected into rabbits which developed useful titers of antibodies after five months. The radioligand for the assay was prepared by acetylating isodesmosine with [3H] acetic anhydride. The bound ligand was separated from free ligand by coprecipitation with human gamma-globulin in 46% saturated ammonium sulfate solution. The sensitivity of the assay was 2 ng isodesmosine. The antiserum was specific for isodesmosine tetraacetate and only desmosine tetraacetate gave appreciable cross-reactivity (4%). The assay was found to be suitable for the accurate estimation of elastin in small samples (5 mg dry weight) of rat and ovine fetal lung tissue and for elastin degradation products in amniotic fluid (0.5 ml).