TRH-like immunoreactivity in rat pancreas and eye, bovine and sheep pineals, and human placenta: non-identify with synthetic Pyroglu-His-Pro-NH2 (TRH)

Extracts from albino rat eyes and pancreas, bovine and sheep pineals and human placenta containing TRH-like immunoreactivity were chromatographed on silica-gel plates. Comparison of elution profiles for TRH-like immunoreactivity with that of TRH revealed the presence of substances other than TRH in these samples. Chromatography of TRH-like immunoreactivity obtained from Rana pipiens skin eluted in two solvent systems produced elution profiles identical with that of synthetic Pyroglu-His-Pro-NH2 consistent with reports that frog skin contains large quantities of TRH. Implications of these findings are discussed.

Demonstration of alpha 1-antitrypsin by immunofluorescence on paraffin-embedded hepatic and pancreatic tissue

Studies were performed in an attempt to improve current immunohistological techniques for the demonstration of alpha 1-antitrypsin (A1AT) in formalin-fixed paraffin-embedded tissues. The unwanted fluorescence (UF) commonly occurring in such procedures was found to be effectively eliminated by immunoadsorption of A1AT antisera with human serum lacking A1AT (Pi-null phenotype) coupled in solid phase to glutaraldehyde-activated aminohexyl-Sepharose 4B. Specificity of the antisera for A1AT was established by subsequent solid phase immunoadsorption against normal human serum bound to AH-Sepharose 4B. Using these techniques, immunoreactive A1AT was demonstrated in the cytoplasm of hepatocytes in liver biopsies obtained from patients with Z and MZ serum phenotypes, and in the cytoplasm of normal pancreatic islet cells.

Immunofluorescence studies indicate that the basic trypsin-kallikrein-inhibitor of bovine organs (Trasylol) originates from mast cells

Using the indirect immunofluorescence technique, the basic kallikrein-trypsin inhibitor of bovine organs, Trasylol, could be localized in tissue mast cells of bovine lung, liver, pancreas and parotid gland. Identification of cells exhibiting specific fluorescence as tissue mast cells was achieved by combined light and electron microscopic diagnosis of bovine liver tissue sections. The presence of Trasylol in mast cells explains the widespread distribution of this inhibitor in functionally totally different organs or tissues of the bovine organism, as determined earlier by biochemical means. Identification of Trasylol as a mast cell constituent will facilitate the search for the biological function of this inhibitory protein in connection with a unique and highly specialized cell population.

Purification and characterization of human pancreatic colipase

Two colipases, named colipase I and colipase II, have been isolated from extracts of human pancreatic gland. The two proteins can be separated by ion-exchange chromatography, isoelectric focusing and slab technique gel electrophoresis. The result of this study indicates that the two colipases, both of which are glycoproteins, have identical amino acid compositions. The pI values were found to be 6.1 for colipase I and 5.8 for colipase II. The different colipases have also been found in human pancreatic juice. The N-terminal amino acid was glycine for both colipase I (gland) and colipase II (juice). Only minor differences were found between the colipases isolated from gland and juice, and colipase I from gland alone was examined in detail.

Studies on the molecular arrangement of RNA in tissues with a selective topo-optical reaction of RNA

Selective demonstration of RNA in tissues was achieved by treating tissue sections with potassium permanganate followed by bisulfite and toluidine blue at pH 1.0 (PBT reaction). It is suggested that this reaction is due to aldehyde groups which are formed by the oxidative cleavage of the pyrimidine rings of RNA which can be selectively demonstrated using bisulfite-toluidine blue as the aldehyde reagent. The specificity of the reaction was tested after RNAase treatment, after acid hydrolysis, and on pure RNA droplets. The aldehyde nature of the reacting groups was checked, after permanganate oxidation, by Schiff's leucofuchsin reagent, and by aldehyde blocking reactions. Two types of intracellular molecular arrangement of RNA molecules could be distinguished by polarization optics after application of the PBT reaction: 1) The strong birefringence, dichroism and metachromatic staining of membrane-bound RNA in ergastoplasm of pancreas, liver and plasma cells indicate a linear (planar) molecular order of RNA molecules on the surface of the membranes, and 2) the isotropic, basophilic staining of RNA not organized in membrane structures (Nissl substance, nucleoli) suggest a random distribution of their dye binding sites.

DL-ethionine treatment of adult pancreatic donors. Amelioration of diabetes in multiple recipients withe tissue from a single donor

Transplantation of adult rat pancreatic islet tissue as a free graft requires the separation of islet from exocrine tissue to avoid host injury or graft destruction by digestive enzymes. The poor yield from islet isolation techniques currently necessitates the use of multiple donors to ameliorate diabetes in a single recipient. DL-ethionine (DLE) is an agent selectively toxic to the exocrine pancreas. We examined the effect of DLE administration on pancreatic digestive enzyme content and islet mass in adult Lewis rats and the ability of such pancreatic tissue dispersed by collagenase digestion without specific islet isolation to ameliorate diabetes when transplanted to the portal vein of syngeneic rats with streptozotocin induced diabetes. Rats fed normal chow supplemented with 0.5% DLE for 14-20 days showed a logarithmic loss of pancreatic mass. Total pancreatic amylase content declined to 0.3 + 0.1 mg, less than 3% of control values (14.3 +/- 1.0 mg). Total insulin content in DLE treated rats was 87 +/- 8 microg, not significantly different from control rats (101 +/- 7 microg). Histological examination confirmed the selective atrophy of exocrine tissue in DLE treated rats. Fresh pancreatic tissue prepared from a single DLE treated donor ameliorated diabetes 75% of the time when transplanted to one or two recipients and 65% of the time when divided between three of four recipients. Tissue prepared from a single DLE treated donor and stored for 24-48 hours ameliorated diabetes 91% of the time when divided between one or two recipients. Only four of 31 diabetic rats transplanted with fresh pancreatic tissue from untreated adult donors became normoglycemic. Pretreatment of adult rats with DLE induces selective exocrine atrophy, permits dispersed pancreatic tissue from a single donor to ameliorate experimental diabetes in up to four recipients, and allows tissue to be preserved by culture for up to 48 hours without specific islet isolation.

Syngeneic transplantation of fetal rat pancreas. III. Effect of insulin treatment on the growth and differentiation of the pancreatic implants after reversal of diabetes

Eight 18-316 fetal pancreases were transplanted to syngeneic alloxan diabetic male rats. Some of the recipients were treated with insulin for a 7-day period immediately after transplant. By previously published clinical criteria, three groups of recipients could be identified after reversal of diabetes by the transplanted tissue: insulin-treated rapid reversal; insulin-treated slow reversal; and control (not treated with insulin). Five animals in each group were sacrificed after glucose tolerance testing for morphologic and hormonal analysis of the transplanted tissue. The insulin-,glucagon-, and somatostatin-positive islet cell masses of the fetal pancreatic implants were quantitated. There was a correlation between the beta cell mass of the implants and the glucose tolerance exhibited by the host animals. The rapid response insulin-treated recipients had significantly greater implant beta cell mass and insulin content compared with the other groups. There was no difference in implant alpha cell mass among the groups, but the insulin-treated implants had a significantly greater glucagon content. The delta cell mass of insulin-treated rapid response was less than that of the other two groups. The results are discussed in relation to previously reported morphometric analysis 15 days after transplantation. The relationships of transplanted beta cell mass, beta cell differentiation, transplant site, and cell-to-cell interactions within the transplanted islet to the control of glucose homeostasis are also discussed.

An immunocytochemical study of the distribution of pancreatic endocrine cells in chicks, with special reference to the relationship between pancreatic polypeptide and somatostatin-immunoreactive cells

Araldite sections of formalin-fixed pancreas from chicks at hatching were treated by an indirect immuno-enzyme technique to reveal cells containing APP, somatostatin, glucagon and insulin. APP cells were found scattered in the exocrine parenchyma. A few were associated with insulin-containing B islets and occasional cells occurred in and around glucagon-containing A islets. Somatostatin-immunoreactive cells were distributed peripherally in A and B islets and were dispersed in the exocrine tissue. APP cells were roughly as numerous in the exocrine parenchyma as somatostatin-immunoreactive cells. Since certain published observations point to the possible occurrence of APP and somatostatin in the same cells, consecutive sections were stained for these hormones. In no case did the two peptides occur in the same cell. Sections subjected to double-staining confirmed this result. Therefore it is likely that the described differences between APP and somatostatin-immunoreactive cells are valid.

Regional distribution and concentration of pancreatic polypeptide in the human and canine pancreas

The regional concentrations of pancreatic polypeptide (PP), insulin, and glucagon and the cellular distribution of PP were studied in 13 human and nine canine pancreases by radioimmunoassay, immunoperoxidase localization, and cell quantitation. PP concentration was highest in both the uncinate process and the head of the human pancreas and in the right lobe of the canine pancreas. In contrast, glucagon and insulin levels were higher in the body and tail of both the human and canine pancreases. Human F-cells, which contain PP, were located primarily at the periphery of the islets, although a few F-cells were scattered throughout the ducts and acini. Canine F-cells were located in ducts, acini, and islets; the relative proportion of canine F-cells in the endocrine and exocrine tissues differed according to location. Cellular quantitation of F-cells in both species correlated significantly with the tissue concentration of PP in all regions studied, validating the use of morphometric techniques to quantitate the regional distribution of PP.

Regranulation of islets of Langerhans and normalization of in vivo insulin secretion in ob/ob mice treated with oxytetracycline

Oxytetracycline (OTC) treatment was associated with regranulation of the islet cells and increased pancreatic insulin content in the ob/ob mouse. This was accompanied by an improvement of the in vivo insulin secretory response to glucose. Because of the wide-ranging effects of OTC on other membrane-related functions, it is postulated that this compound may exert ist effect by altering the composition of cellular membranes.

Sensitive radioimmunoassay for somatostatin using N-[125I]-Tyr-somatostatin as labelled antigen

A sensitive radioimmunoassay for somatostatin using N-[125I]-Tyr-somatostatin is described and compared with that using [125I]-Tyr1-somatostatin. The minimum detectable amount of somatostatin using N-[125I]-Tyr-somatostatin as tracer was 0.1 to 0.5 pg, which is approximately 10-fold lower than the lower detection limit of the RIA using [125I]-Tyr1-somatostatin. Moreover, it was found that the shelf-life of N[125I]Tyr-somatostatin was prolonged in comparison with labelled Tyr1-somatostatin. Human pancreatic and gastric extracts displayed immunological similarity to synthetic somatostatin tetradecapeptide.

Metabolic and endocrine responses to a standard mixed meal. A physiologic study

In order to study endocrine and metabolic responses to normal food ingestion, 8 'healthy' subjects received a standard mixed meal which reflected the composition of Western diet (CHO 47%, protein 23%, fat 26%, alcohol 4%), in 20 min. Before and after the meal, in each subject glucose, lactate, FFA, insulin, C-peptide, glucagon and HGH were determined. The results showed that glycemic and insulinemic responses were not very different from those observed after the classical oral glucose tolerance test. Plasma FFA and blood lactate decreased progressively after the meal. Plasma glucagon and HGH showed opposite changes: pancreatic glucagon rose and HGH slightly declined after composite food ingestion.

Influence of age on the sensitivity of the rat to streptozotocin

The relationship between age and sensitivity to the diabetogenic effect of streptozotocin was investigated. Changes in the serum levels of several parameters (glucose, immunoreactive insulin, lipids), as well as changes of the pancreatic insulin content were monitored at 2, 4, 8, 24 and 48 h after the intravenous administration of different doses of streptozotocin in rats of various weights. Different concentrations of blood glucose and lipid and different amounts of pancreatic immunoreactive insulin could be found in rats of different ages 24 and 48 h after injection of the same dose of the drug (in mg/kg body weight). Also, age-dependent changes of serum immunoreactive insulin could be observed as early as 4 h after streptozotocin administration. All these changes indicate that the sensitivity of the rat to the diabetogenic effect of streptozotocin is inversely related to the age of the animals. Most likely, age-dependent pancreatic factors have an important role. In fact, the changes of the minimum dose of streptozotocin required to cause diabetes in rats of different weights closely parallel the age-related changes of the total immunoreactive insulin content of the pancreas of the intact rats. The role of other age-related factors which may influence the effectiveness of streptozotocin action is briefly discussed.

Distribution of cell surface saccharides on pancreatic cells. II. Lectin-labeling patterns on mature guinea pig and rat pancreatic cells

The surface saccharide composition of collagenase-dispersed pancreatic cells from adult guinea pig and rat glands was examined by using eight lectins and their ferritin conjugates: Concanavalin A (ConA); Lens culinaris (LCL); Lotus tetragonolobus (LTL); Ricinus communis agglutinins I and II (RCA I, RCA II); Soybean agglutinin (SBA); Ulex europeus lectin (UEL); and wheat germ agglutinin (WGA). Binding studies of iodinated lectins and lectin-ferritin conjugates both revealed one population of saturable, high-affinity receptor sites on the total cell population (approximately 95% acinar cells). Electron microscopy, however, revealed differences in lectin-ferritin binding to the plasmalemma of acinar, centroacinar, and endocrine cells. Whereas acinar cells bound heavily all lectin conjugates, endocrine and centroacinar cells were densely labeled only by ConA, LCL, WGA, and RCA I, and possessed few receptors for LTL, UEL, and SBA. Endocrine and centroacinar cells could be differentiated from each other by using RCA II, which binds to centroacinar cells but not to endocrine cells. Some RCA II receptors appeared to be glycolipids because they were extracted by ethanol and chloroform-methanol in contrast to WGA receptors which resisted solvent treatment but were partly removed by papain digestion. RCA I receptors were affected by neither treatment. The apparent absence of receptors for SBA on endocrine and centroacinar cells, and for RCA II on endocrine cells, was reversed by neuraminidase digestion, which suggested masking of lectin receptors by sialic acid. The absence of LTL and UEL receptors on endocrine and centroacinar cells was not reversed by neuraminidase. We suggest that the differential lectin-binding patterns observed on acinar, centroacinar, and endocrine cells from the adult pancreas surface-carbohydrate-developmental programs expressed during morphogenesis and cytodifferentiation of the gland.

[Cadmium content of vegetable foods in the effective range of a lead smelting plant]

In the effective range of a lead smelting plant, the repercussions of cadmium emissions (mainly past) on vegetables, fruit, soil and drinking water as well as of immissions were investigated by means of atomic absorption spectrometry. As compared to the "normal" cadmium level, the cadmium contents in vegetables and fruit were some 2- to 85-fold higher; and those in soils, some 70- to 230-fold. The mean contents in vegetables ranged from 0.4 to 25.5 p.p.m. (on a dry-weight basis); those in fruit, from 0.09 to 1.17 p.p.m. Cadmium concentrations varying from 6.8 to 22.8 p.p.m. were found in soil samples. The drinking water contained 0.009 p.p.m. of cadmium. The mean cadmium contents in the atmosphere and the sedimentary dust were 0.007 mg/m3 and 0.550 mg/m2/30d, respectively. In the territory investigated, the total human uptake of cadmium supplied by vegetables, fruit, potatoes, drinking water and air is 3.3-32.6 microgram/d. The following cadmium levels were found in human organ samples obtained at necropsy: right and left renal cortex, 33.99 and 35.98 p.p.m., respectively; liver, 3.14 p.p.m.; lungs, 0.63 p.p.m.; pancreas, 1.47 p.p.m.; brain stem, 0.16 p.p.m.

The localization of enzyme activities in the pancreatic appendages of Sepia officinalis L. (Cephalopoda)

In this study, enzyme activities of the pancreatic appendages of the ductus hepatoPancreas (the so-called "pancreas") in Sepia officinalis L. have been demonstrated by light and electron micicroscopical methods: Malate dehydrogenase, monoamine oxidase, acid phosphatase, beta-glucuronidase, adenosine triphosphatase and carbonic anhydrase were shown by the former, and monoamine oxidase, catalase, glutamic oxalacetic transaminase, choline esterase (non-specific), alkaline phosphatase, acid phosphatase and carbonic anhydrase by the latter technique. The correlation between enzyme activity and distribution, and the presumed function of the two pancreatic epithelia is discussed.

Is GIP a glucagon cell constituent?

"Gastric inhibitory peptide" or "glucose-dependent insulin-releasing peptide" (GIP) is a member of the gut hormone family. Its physiological action is thought to be related to its insulinotrophic effect. The occurrence and distribution of GIP was studied by immunohistochemistry. In all species examined including man, GIP immunoreactivity was found to reside in the glucagon cells of the pancrease and gut. Three pancreatic glucagonomas were found to contain numerous cells displaying GIP and glucagon immunoreactivity. The GIP antiserum used did not cross react with either pancreatic-type or gut-type glucagon (GLI).

Ultrastructural localization of pancreatic polypeptide in the F cell of the dog pancreas

The F cell of the dog pancreas has been identified as the specific cell type containing pancreatic polypeptide. This localization of pnacreatic polypeptide was accomplished by immunocytochemical staining of ultrathin sections and direct electron microscopic identification. Verification of the specificity of the reaction was obtained by blocking experiments on serial sections of the same cell. It is proposed that the name F cell be used for defining in all species the islet cell that contains pancreatic polypeptide.

Cerebral localization of insulin by immunofluorescence

An immunohistochemical procedure was used to detect cells which appear to bind insulin in the mouse brain. Strong fluorescence was observed in the cell bodies and processes of tanycytes lining the third ventricle and in the choroid plexi. These findings suggest that insulin enters the central nervous system, and indicate a route for its possible transport. This adds credence to earlier observations that the hypothalamic ependymal cells and processes form a highly organized and functional system, with different cells selectively absorbing (or sensing) particular substances from the systemic and ventricular circulations and transporting them (or information about them) to specific neuron receptors in the hypothalamus.