Pharmacological analysis of changes in the contentof diene conjugation, methyl esters of fatty acids of liver lipid fractions by cholinotropic agents during the overcooling of rats

The analysis of changes in the content of diene conjugation, fatty acid methyl esters (FAME) C20 of total lipids, fractions of free fatty acids (FFA) in the liver of animals exposed to overcooling for 3 hours and for 5 days after administration of cholinergic agents has been made. The obtained results indicate changing in the content of methyl esters of fatty acids and diene conjugation of FFA fractions after administration of pharmacological agents as neostigmine, pilocarpine, and atropine to animals on the background of cooling. Changes in the content of diene conjugation coincide with changes in the content of fatty acids (FA) C20 : 4 Δ-5,8,11,14 eicosatetraenoic acids (FA Arakhia) when pilocarpine or atropine was used. The presence of reciprocity was revealed. Basing the reciprocity factor, it was suggested that there was a possible effect of muscarine-sensitive structures of the plasmic membrane hepatocytes on the link between the content of FAME C20 Arakhia, phospholipase A2 activity and the change in the content of diene conjugation in fraction of liver FFA. A possible effect of cholinotropic agents on phospholipase A2 activity in the period of animal cooling was suggested.

Spermiogenesis and sperm ultrastructure of Carmyerius endopapillatus (Digenea, Gastrothylacidae), a parasite of Bos taurus in Senegal

Ultrastructural study of spermiogenesis and of the spermatozoon of Carmyerius endopapillatus has enabled to describe some characteristics of this digenea. The intercentriolar body situated between the two striated roots and the two centrioles, presents a symmetric organization. Both external bands of this intercentriolar body are made up of a row of granules. During spermiogenesis, a flagellar rotation of 90° is described. The old spermatid does not present external ornamentations. The spermatozoon is characterized, in its anterior region, by the presence of a lateral expansion exhibiting one spinelike body. In C. endopapillatus, external ornamentations are localized only at the level where the lateral expansion appears. The posterior extremity of spermatozoon exhibits a nucleus surrounded by a plasmic membrane lacking microtubules, but presenting a small lateral expansion. This is the first species of Gastrothylacidae family studied by transmission electron microscopy.

Ultrastructural aspects of the intercellular bridges between female bee germ cells

The germline cells in the ovary of the female bee are interconnected by intercellular bridges kept open by cytoskeletal reinforcements in the plasmic membrane. These bridges among the germline cells display a dynamic behavior and probably act in the determination of the oocyte among the cells of the clone formed by the premeiotic mitoses, subsequently forming a pathway that enables the products synthesized by the nurse cells to reach the oocyte during its maturation. The cytoskeletal elements in the intercellular bridges of bee gonads are basically microfilaments and microtubules, but another type of filament (thick, of non-defined nature, associated with elements of the endoplasmic reticulum) is present in the bridges between the premeiotic cystocytes. This filament crosses the bridge, using microfilaments to fasten itself to the plasmic membrane. These filaments appear to control the span of the bridge. Upon completion of the proliferation phase the cystocytes take on a rosette shape, and a fusome formed by the convergence of the bridges appears at their center. The thick filaments are not present in this conformation. The differentiation of the oocyte and the nurse cells leads to a new change, in which the bridges are reoriented to convey the content of the future nurse cells to the oocyte.

Investigation of the inhibitory effects of HA-1077 and Y-32885 on the translocation of PKCβI, PKCβII and PKCζ in human neutrophils

To transmit the information inside the cell, one possibility is the action of an enzyme called kinase that phosphorylates other proteins. To study these enzymes, chemical compound synthesis was needed to know the function and the mechanism of activation. The major difficulty is creating a specific molecule for one kinase. In this study, we test the action of Rho-kinase inhibitors (HA-1077 and Y-32885) on protein kinase C (PKC) in the respiratory burst in the human polymorphonuclear neutrophils. We have shown that these compounds could inhibit the anion superoxide production. To prove their action on PKC, we have shown a decrease of binding of a specific ligand (phorbol-12,13-dibutyrate) with each inhibitor. During its activation, PKC was translocated from the cytoplasm to the plasmic membrane. We have also shown an inhibition of this translocation, proving an inhibition of PKC by HA-1077 and Y-32885.

Globular and asymmetric acetylcholinesterase in frog muscle basal lamina sheaths.

After denervation in vivo, the frog cutaneus pectoris muscle can be led to degenerate by sectioning the muscle fibers on both sides of the region rich in motor endplate, leaving, 2 wk later, a muscle bridge containing the basal lamina (BL) sheaths of the muscle fibers (28). This preparation still contains various tissue remnants and some acetylcholine receptor-containing membranes. A further mild extraction by Triton X-100, a nonionic detergent, gives a pure BL sheath preparation, devoid of acetylcholine receptors. At the electron microscope level, this latter preparation is essentially composed of the muscle BL with no attached plasmic membrane and cellular component originating from Schwann cells or macrophages. Acetylcholinesterase is still present in high amounts in this BL sheath preparation. In both preparations, five major molecular forms (18, 14, 11, 6, and 3.5 S) can be identified that have either an asymmetric or a globular character. Their relative amount is found to be very similar in the BL and in the motor endplate-rich region of control muscle. Thus, observations show that all acetylcholinesterase forms can be accumulated in frog muscle BL.

Le virus de la rubéole. II. Réplication dans les cellules Vero et effets de l'actinomycine D et du cycloheximide

Budding at the plasmic membrane is the primary mode of production of rubella virus in Vero cells. Intense cytopathic effect is observed even if only 10% of the cells are infected. Actinomycin D has little effect on the multiplication of rubella virus but cycloheximide inhibits its growth. This inhibition is probably due to the reduction of cellular protein synthesis and not to a direct action of the inhibitors on the virus multiplication. Viral proteins in infected cells have not been demonstrated. The presence of a viral substance inhibiting normal cellular synthesis is discussed. [Journal translation]