[The structure and composition of the complex that provides the adhesion of the cellular layers during the morphogenesis of the human embryonic adenohypophysis]. / Struktura i sostav kompleksa, obespechivaiushchego adgeziiu kletochnykh plastov v khode morfogeneza adenogipofiza zarodyshei cheloveka.

The area of contact between adenohypophysis and diencephalon rudiments of human embryos (5-7 weeks of development) was studied using immunohistochemistry and electron microscopy. Basement membranes of Rathke's pouch ectoderm and of diencephalon bottom neuroectoderm are connected by means of a complex consisting of thin fibrous material and collagen-like fibrils. After Ca+2 and Mg+2 ions removal, this complex with basement membranes was separated from epithelial layers. The material in the contact area differed in its composition from the basement membranes covering the adenohypophysis and diencephalon rudiments by the high content of tenascin and the absence of EDB-fibronectin. Other basement membrane components (collagen IV, heparan-sulphate proteoglycans, entactin and laminin) were also present in this area. Tenascin accumulation was also found in Rathke's pouch epithelium and cavity.

[The ultrastructural characteristics of the corticotropic cells of the rat adenohypophysis]. / Ul'trastrukturnaia kharakteristika kortikotropnykh kletok adenogipofiza krys.

Ultrastructural characteristics of corticotropic cells have been studied on serial semithin and ultrathin sections of the hypophysis from intact rats by the immunofluorescence and electron microscopic methods. It is shown that the population of corticotropic cells is heterogeneous and consists of degranulated, moderate granulated, hypergranulated cells and transitional forms among them. Ultrastructurally corticotropic cells correspond to Siperstein-Nakayama's ACTH cells. Kurosumi-Kobayashi "corticotrophs" fail to react with the antiserum to ACTH, so they have not regard for its production.

[Effect of exogenous somatotropin on the ultrastructure of somatotropic cells in hyperthyroid rats]. / Vliianie ékzogennogo somatotropina na ul'trastrukturu somatotropnykh kletok u gipertireoidnykh krys.

Marked ultrastructural changes indicating a decrease in the cell functional activity occur in the somatotropic cells of rats after chronic hyperthyroidism with 1-thyroxin. Exogenous somatotropin produces no effect on these ultrastructural changes.

[Ultrastructural changes in the thyro- and somatotropes of hypothyroid rats as affected by exogenous somatotropin]. / Ul'trastrukturnye izmeneniia v tireo- i somatotrofakh gipotireoidnykh krys pod vliianiem ékzogennogo somatotropina.

The state of somatotropic and thyrotropic adenohypophyseal functions of thyroidectomized rats after chronic injections of bovine somatotropin was studied. The adenohypophyseal somatotropin content increased by 22% per gland. The blood serum immunoreactive thyrotropin concentration was 0.925 +/- 0.063 microgram/ml in intact animals, 3.99 +/- 0.74 microgram/ml in thyroidectomized- and 1.27 +/- 0.19 microgram/ml in thyroidectomized rats, given somatotropin. According to electronic microscopy, hypothyrosis is characterized by an elevated functional somato- and thyrotrop activity, markedly decreased after somatotropin injection.

[Functional and ultrastructural changes in the adenohypophysis in obesity]. / Funktsional'nye i ul'trastrukturnye izmeneniia adenogipofiza.

The indices of some tropic adenohypophyseal functions of obese patients were compared with ultrastructural reaction of the adequate adenocytes of rats with experimental hypothalamic obesity. It was shown that in obesity significant functional and structural changes occur in adenohypophyseal cells, their extent being considerably associated with the excessive body mass. In pronounced obesity, a decrease in somato- and thyrotropic- and an increase in gonado- and corticotropic adenohypophyseal functions are seen, manifesting in ultrastructural changes of appropriate adenocytes. The results obtained allow a conclusion, that one of the mechanisms of obesity development is the changed secretory potency of adenohypophyseal cells, producing hormones, which exert a substantial influence upon lipogenesis and lipolysis processes.

[Functional and morphological changes in the islands of Langerhans in obesity]. / Funktsional'nye i morfologicheskie izmeneniia ostrovkovogo apparata podzheludochnoi zhelezy pri ozhirenii.

Functional changes in pancreatic islets seen in obese patients were compared with morphological and ultrastructural alterations in islet cells in rats during varying time of the experimental hypothalamic obesity development. The blood level of insulin and C-peptide in obese patients increases with the disease severity, but functional B-cell reserves tend to decrease as shown by glucose tolerance test. Reduction in glucagon release is seen in insulin hypoglycemia. A fall in B cell reserves is caused by their functional overtension, destruction and replacement of the pancreatic parenchyma by the connective tissue. The main morphological reason for glucagon release lowering in patients with pronounced obesity is reduction of A cell number. An elevation of somatostatin level in the blood of obese patients with a simultaneous decrease in D cell number in pancreatic islets of experimental animals indicates that this rise is stipulated by intensified hypothalamic somatostatin secretion.

[Changes in lactotropocytes following administration of a pineal factor which stimulates prolactin secretion]. / Izemeniia laktotropotisitov pri vvedenii faktora épifiza, stimuliruiushchego sekretsiiu prolaktina.

Effects of a factor extracted from the epiphysis on the ultrastructure of adenohypophyseal cells of immature female rats have been stuided. This factor exerted it effects mainly on lactotropocytes on stimulating their differentiation and proliferation. In the lactotropocyte cytoplasm, ultrastructural changes were noticed in elements of the protein-synthesizing system suggesting a sharp enhancing of the synthesis and release of prolactin. The study supported the earlier supposion that the epiphyse may contain a factor similar in its effect to hypothalamic prolactoliberin.

[Ultrastructural changes in rat hepatocytes with diabetes and insulin administration]. / Ul'trastrukturnye izmeneniia v gepatotsitakh krys pri diabete i vvedenii insulina.

Ultrastructural alterations in rat hepatocytes were studied at different periods following injection of alloxan. Visible increase in the size of mitochondria, decrease in development of rough endoplasmic reticulum and proliferation of smooth endoplasmic reticulum elements have been found. These alterations increased with time after alloxan injection and were accompanied by the appearance of lysosome-like bodies and autophagic vacuoles in hepatocytes cytoplasm. Repeated administration of insulin normalized the ultrastructure of hepatocytes of diabetic animals.

[Changes in RNA biosynthesis and ultrastructure of hepatic cells as affected by sodium ribonucleate]. / Iemenenie biosinteza RNK i ul'trastruktury kletok pechenipod vliianiem ribonukleinata natriia.

Sodium ribonucleate (per os application) increased the biosynthesis of mitochondrial, nuclear and cytoplasmic RNA in the rat liver and transportation of nuclear RNA into the cytoplasm. Administration of ribonucleate changed the ultrastructure of hepatocytes, increased nuclear and nucleolar diameter, the number of rough endoplasmic elements, reticulum and glycogen particles and decreased the size of the mitochondria. This suggests that sodium ribonucleate can stimulate the biosynthesis of RNA and change the ultrastructure of hepatocytes also with application per os.

[Ultrastructural changes in the livers of rats following multiple injections of corticotropin and sodium ribonucleinate]. / Ul'trastrukturnye izmeneniia v pecheni krys pri mnogokratnykh in"ektsiiakh kortikotropina i ribonukleinata natriia

The mechanism of the corticotropin (ACTH) action was studied. It was found that daily injections of ACTH-zinc-phosphate (5 un./100 g) to intact albino rats for 14 days result in a disturbance of the hepatocytes ultrastructure. When the hormone was injected in combination with sodium ribonucleate (5 mg/100 g), the deviations were less pronounced, injections of the hormones to adrenalectomized rats did not change the ultrastructure of hepatocytes.