Increase In Smooth Endoplasmic Reticulum Research Articles

Histological study on the possible protective role of Moringa Oleifera leaves extract on Paracetamol induced liver damage in adult male albino rats

Introduction: Moringa oleifera is a tropical tree whose leaves are rich in antioxidant compounds. Paracetamol hepatotoxicity is a significant public health concern. Aim: The aim of this study was to investigate the possible protective role of Moringa oleifera leaves (MOL) aqueous extract on paracetamol induced liver injury in adult male albino rats.Materials and Methods: Forty adult male albino rats were used in the current study and were divided into four equal groups,: Group I served as control; Group II were given MOL for 14 days; Group III were given water for 7 days followed by paracetamol for another seven days; Group IV were given MOL for 14 days and Paracetamol on the seventh day for 7days.All medications were given by nasogastric tube. Specimens of liver were excised and processed for histological and histochemical studies. Blood samples were collected for biochemical study. Statistical analysis of the results was done.Results: MOL administration in group II didn’t affect hepatic architecture or liver function tests. There was a significant increase in glutathione peroxidase and catalase activity and no significant difference in malondialdehyde level as compared to control. Paracetamol administration led to vacuolization of hepatocytes, cellular infiltrations and congestion in central and portal veins, with apparent increase in number of cholangiocytes. There were also significant decrease in the area percentage of PAS positive granules and significant decrease in area percentage of collagen fibers as compared to control. By electron microscope, distorted mitochondria, decrease of rough endoplasmic reticulum and increase of smooth endoplasmic reticulum & collagen fibrils were observed. Administration of Moringa before paracetamol ameliorated damaging effects of paracetamol. Minimal cellular infiltrations and apparent increase in number of cholangiocytes were still observed. Conclusion: MOL extracts could protect the liver against paracetamol effects through inhibition of lipid peroxidation and enhancement of antioxidant enzymes.

Ultrastructure of Central Cell before and after Fertilization in Sugar Beet ( Beta vulgaris )

The ultrastructural changes of central cell before and after fertilization were observed with TEM to provide more information for reproductive biology of sugar beet and relative research.The results indicated that the changes of central cell before and after fertilization mainly occurred in nucleus and cytoplasm around.Fusion of polar nuclei took place early at bud stage.The nucleolus of secondary nucleus was bipolar with notable fibrous and particle core.Sometimes,there was extra small nucleolus and nucleolus vacuole.Cytoplasm surrounding secondary nucleus was rich in organelles,including mitochondria,plastids with or without starch grain,Golgi body,ribosomes and rough endoplasmic reticulum(rER).After fertilization,a striking feature of cytoplasm surrounding nucleus was the well developed amoeboid plastids,which were numerous and various,filling with starch gains.Soon after that,primary endosperm nucleus divided into two free nuclei.During division,nucleolus disappeared and nuclear membrane disintegrated into small vesicles.Also,there was an obvious decrease in rER and an increase in smooth endoplasmic reticulum(sER).Overall,central cell was active before and after fertilization.

Thematic review series: Skin Lipids. Sebaceous gland lipids: friend or foe?

Sebaceous glands are intriguing glands that are found throughout the human body except on the palms of the hands and soles of the feet. The true function of these glands has yet to be determined, but there are several theories, including antioxidant effects, antibacterial effects, and transport of pheromones. Sebaceous glands produce lipids that are involved in the pathogenesis of one of the most prevalent diseases of adolescence, acne. Although the majority of lipids produced by the sebaceous gland are also produced in other areas of the body, there are two that are characteristic of the sebaceous gland, wax esters and squalene. This review seeks to present an update on the physiology of the sebaceous glands, with particular emphasis on the production of sebaceous lipids.

Pathological reactions and recovery of hepatopancreatic digestive cells from the marine snail Littorina littorea following exposure to a polycyclic aromatic hydrocarbon

The aim of this study was to investigate the cellular pathological responses of hepatopancreatic digestive cells from the periwinkle Littorina littorea exposed to the polycyclic aromatic hydrocarbon (PAH) fluoranthene and to ascertain whether any injurious effects were reversible within the experimental time scale. A secondary objective was to establish the relationship of the various reactions to animal health status, using lysosomal stability as an index of well-being. Exposure of snails to a concentration of 335 microgl(-1) (1.7 microM) fluoranthene (seawater renewed and spiked daily with fluoranthene) for 5 days resulted in a reduction in lysosomal stability (neutral red retention) and endocytosis; and an increase in smooth endoplasmic reticulum (ER) and 7-ethoxycoumarin-o-deethylase (ECOD; measured as cyano-ECOD) activity measured in isolated live digestive cells. Exposed snails treated with clean seawater for a further 8 days resulted in a return to control levels of lysosomal stability, ECOD and ER; endocytosis showed only a partial recovery. Multi-variate and uni-variate analysis showed that there were strong correlations between the various cellular biomarker responses. These findings are interpretable within the current framework of molluscan biomarker responses to PAHs. Principal component analysis was used to derive the first principal component for endocytosis, ER and ECOD reactions and these were plotted against lysosomal stability as a measure of cellular well-being. The resulting significant regression represents the mapping of the individual biomarkers within health status space for a gradient of fluoranthene toxicity. From this analysis, we concluded that endocytosis is an indicator of healthy snails while proliferation of ER and to a lesser extent induced ECOD are indicative of dysfunction and reduced health. Finally, the results indicate that stress induced by chronic exposure to a PAH is reversible.

Experimental evidence for a direct cytotoxicity of Loxosceles intermedia (brown spider) venom in renal tissue.

Brown spider (Loxosceles genus) venom causes necrotic lesions often accompanied by fever, hemolysis, thrombocytopenia, and acute renal failure. Using mice exposed to Loxosceles intermedia venom, we aimed to show whether the venom directly induces renal damage. The experimental groups were composed of 50 mice as controls and 50 mice that received the venom. Light microscopic analysis of renal biopsy specimens showed alterations including hyalinization of proximal and distal tubules, erythrocytes in Bowman's space, glomerular collapse, tubule epithelial cell blebs and vacuoles, interstitial edema, and deposition of eosinophilic material in the tubule lumen. Electron microscopic findings indicated changes including glomerular epithelial and endothelial cell cytotoxicity as well as disorders of the basement membrane. Tubule alterations include epithelial cell cytotoxicity with cytoplasmic membrane blebs, mitochondrial changes, increase in smooth endoplasmic reticulum, presence of autophagosomes, and deposits of amorphous material in the tubules. We also found that the venom caused azotemia with elevation of blood urea levels but did not decrease C3 complement concentration or cause hemolysis in vivo. Confocal microscopy with antibodies against venom proteins showed direct binding of toxins to renal structures, confirmed by competition assays. Double-staining immunofluorescence reactions with antibodies against type IV collagen or laminin, antibodies to venom toxins, and fluorescent cytochemistry with DAPI revealed deposition of toxins in glomerular and tubule epithelial cells and in renal basement membranes. Two-dimensional electrophoresis showed venom rich in low molecular mass and cationic toxins. By immunoblotting with antibodies to venom toxins on renal extracts from venom-treated mice, we detected a renal binding toxin at 30 kD. The data provide experimental evidence that L. intermedia venom is directly involved in nephrotoxicity.

Protective effects of ascorbic acid, dl-alpha-tocopherol acetate, and sodium selenate on ethanol-induced liver damage of rats.

In this study, the effect of a combination of vitamin C (ascorbic acid), vitamin E (dl-alpha-tocopherol acetate), and selenium (sodium selenate) on ethanol-induced liver damage in rats was investigated, morphologically and biochemically. The ethanol-induced injury was produced by the administration of 1 mL of absolute ethanol to each rat. Animals received vitamin C (250 mg/kg), vitamin E (250 mg/kg), and selenium (0.5 mg/kg) (ViCESe) for 3 d 1 h prior to the administration of absolute ethanol. In the liver of the animals given ethanol, the degenerative changes such as extreme hyperemia, vacuolization in cells of portal areas, a dilation in sinusoids, mononuclear cell infiltration, a swelling in cisternae of granular endoplasmic reticulum and in mitochondrial cristae, an increase in smooth endoplasmic reticulum, many lipid vacuoles were observed both light and electron microscopically. A similar structure was usually distinguished when compared with control animals, in rats given ethanol + ViCESe. In this group, the findings indicating cellular damage were either not observed at all or were decreased. In the group administered ethanol, a reduction of the blood glutathione (GSH) level and increases in serum values of alanine aminotranserase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) activities were observed, whereas in the control group, the reverse was found to occur. On the other hand, in the group in which ethanol + ViCESe was administered, it was observed that the blood GSH value and serum ALP and ALT activities increased and serum AST, LDH, and GGT activities decreased. As a result, the present study indicates that ViCESe because of their antioxidant activity against ethanol damage have a protective effect on the liver.

Ultrastructural, immunohistochemical and biochemical investigations of the rat liver exposed to experimental diabetes und acute hypoxia with and without application of Ginkgo extract

The aim of this paper was to investigate the effect of streptozotocin-induced diabetes by i.p. bolus injection of streptozotocin at 60 mg per kg bodyweight over four months and additional acute respiratory hypoxia (20 min. duration, 5% oxygen v/v), and also the protective effect of Ginkgo biloba extract (EGb 761) on Wistar rat liver under these experimental conditions. Diabetic and additional hypoxic alterations in histology and ultrastructure were subjected to qualitative and quantitative analysis, collagen was investigated by immunohistochemistry, and some biochemical parameters of oxidative stress were determined. Diabetes caused an increase in the size of the hepatocytes and their nuclei with a decrease in nucleus-to-plasma ratio and glycogen content. Connective tissue was variably increased in individual cases as shown by routine histological staining. EGb did not influence these data. Ultrastructural morphometry revealed a significant reduction in rough endoplasmic reticulum (rER) and a significant increase in smooth endoplasmic reticulum (sER) through diabetes, an increase under EGb protection, with no significant alteration under hypoxia. The volume fraction of mitochondria was significantly increased after induction of diabetes but less increased in the protected group. Additional hypoxia reduced this parameter. The mean cross-section area of mitochondria was significantly elevated in all diabetic groups compared to controls. Volume density of mitochondrial cristae was significantly diminished in all diabetic groups; EGb could only improve this parameter in the diabetic-hypoxic group.

Relaxin causes changes of the liver. In vivo studies in rats.

During pregnancy, the liver undergoes metabolic adjustments directed to fulfil the needs of the mother and the growing fetus. This study was designed to verify whether relaxin, a hormone related to pregnancy, may induce histochemical and ultrastructural modifications of hepatocytes which can be related to metabolic changes. Estrogen-primed female rats were treated with relaxin (10 microg in repository vehicle) for 18 h. Additional male rats were treated with relaxin (10 microg/day in PBS) for 4 days. Appropriate vehicle-treated rats were used as controls. After fasting, the rats were killed and liver fragments were processed for light and electron microscopy and for computer-assisted morphometry of PAS-positive glycogen deposits and acid phosphatase-reactive organelles. In both sexes, the relaxin-treated rats underwent a significant decrease in the amount of glycogen in the hepatocytes as compared with the controls. These changes were accompanied by an increase in smooth endoplasmic reticulum, endocytosis vesicles and lysosomes. These findings show that relaxin promotes glycogen depletion and induces morphological changes of hepatocytes which are consistent with functional activation. It is suggested that relaxin might play an important role in hepatic metabolic adjustments occurring during pregnancy.

Liver tumor promoting effects of fenbendazole in rats.

In order to examine whether fenbendazole has tumor-promoting activity, a total of 70 male Fischer 344 rats were initiated with a single intraperitoneal injection of 100 mg/kg of diethylnitrosamine (DEN) or were given the saline vehicle alone; beginning 1 wk later, rats were given a diet containing 3,600; 1,800; 600; 200; 70; or 0 ppm of fenbendazole for 8 wk. Subgroups of 5 rats each from the DEN+ 1,800; DEN+0; 1,800; and 0 ppm groups were euthanatized after 1 wk of fenbendazole treatment, and the remaining animals were euthanatized at 8 wk. After 1 wk, relative liver weights (ratios to body weights) were significantly increased in the DEN+ 1,800 and 1,800 ppm groups, and based on light microscopy, periportal hepatocellular hypertrophy was evident in these groups. After 8 wk, relative liver weights were significantly increased in the groups given > or =600 ppm with or without DEN initiation. Periportal hepatocellular hypertrophy, characterized by a marked increase in smooth endoplasmic reticulum, was observed in the groups given > or =600 ppm with or without DEN initiation. Induction of cytochrome P-450 (CYP) 1A2, 2B1, or 4A1 was noted in the fenbendazole-treated groups with or without DEN initiation; that associated with CYP 1A2 was most marked. Positive immunostaining for anti-CYP 1A1/2 or CYP 2B1/2 was observed diffusely in the livers of animals in the DEN+1,800 and DEN+3,600 ppm groups. The numbers and areas of connexin 32 (Cx32)-positive spots per square centimeter in centrilobular hepatocytes were significantly decreased in an almost dose-dependent manner with fenbendazole treatment after DEN initiation. In situ hybridization for Cx32 mRNA revealed a remarkable decrease in its expression in the centrilobular hepatocytes in the DEN+70 ppm group. The numbers of glutathione S-transferase placental-form positive single cells (plus mini foci) were significantly increased in the DEN+ 1,800 and DEN+3,600 ppm groups. Since those agents that induce CYP 2B1/2 isozymes and reduce Cx32 in centrilobular hepatocytes have been suggested to be liver tumor promoters, the present results indicate that fenbendazole may be a liver tumor promoter.

Subchronic Toxicity Studies of Sucrose Acetate Isobutyrate (SAIB) in the Ratand Dog

Preliminary short-term toxicity studies of sucrose acetate isobutyrate (SAIB) in the dog demonstrated that addition of this additive to the diet was associated with an increase in liver size and elevated serum alkaline phosphatase activity with no evidence of pathological change by light microscopy. To determine the basis for these changes, a 12-week oral toxicity study of SAIB was conducted in the dog and a similar study was performed in the rat. SAIB was fed in the diet to groups of six beagle dogs of each sex at 0, 0.5, 1.0, 2.0 and 4.0%. SAIB was also fed to groups of 40 Sprague--Dawley rats of each sex at levels of 0, 2.5, 5.0 and 10.0%. In the rat study, in addition to routine toxicology parameters, hepatic microsomal enzyme induction was determined using a zoxazolamine hypnotic test, urinary ascorbic acid excretion and determination of hepatic carboxylesterase activity. Sodium phenobarbital was fed to groups of 20 rats of each sex at a dose of 100mg/kg body weight/day by gavage as a positive control for hepatic microsomal enzyme induction. In the dog study, routine toxicological tests were supplemented by tests for bromsulfophthalein (BSP) retention, histochemical staining of liver sections for glycogen, phosphorylase, succinate dehydrogenase, and acid and alkaline phosphatases. Levels of liver lipid, protein, glycogen and carboxylesterase activity were also determined. Electron microscopic examinations were made on liver sections from the dog study at the end of the 12-week SAIB feeding period and after a 2-week withdrawal period. Administration of SAIB to rats did not reveal evidence of any effect on hepatobiliary function, and there was no indication of microsomal enzyme induction. Body weight gain of male rats fed SAIB was decreased, probably as the result of decreased palatability of the diet; SAIB did not affect body weight gain in females. The changes observed in the dogs fed SAIB included increased serum alkaline phosphatase activity with no change in serum alanine aminotransferase, aspartate aminotransferase or lactic dehydrogenase activity and no change in serum electrolyte, serum protein, glucose or bilirubin levels. No haematological changes were observed. BSP retention was observed at all SAIB dose levels. There were no SAIB-related pathological changes in any organ when examined by light microscopy. Examination by electron microscope revealed dilatation of bile canaliculi and an increase in smooth endoplasmic reticulum compared with controls. Histochemical studies also indicated increased enzyme activity of the bile canaliculi. The electron-mocroscope-revealed changes were completely reversed during a 2-week treatment withdrawal period. The dog study did not establish a no-effect level for changes in hepatobiliary function induced by feeding SAIB.

Liver tumour-promoting effects of oxfendazole in rats

To examine whether oxfendazole has tumour-promoting activity, a total of 100 male Fisher 344 rats were initiated with a single ip injection of 100 mg/kg of diethylnitrosamine (DEN) or given saline vehicle alone and starting 1 wk later given diet containing 500, 250, 100, 10 or 0 ppm of oxfendazole for 8 wk. Sub-groups of five rats each from the DEN plus 250 and 0 ppm groups were killed after wk 1 of oxfendazole treatment and the remaining animals at wk 8. At the termination relative liver weights were significantly increased in the DEN-initiated and non-initiated groups treated with 250 ppm and 100 ppm or more, respectively, compared with the corresponding controls values. Light microscopical examination showed centrilobular hepatocellular hypertrophy in all animals receiving 100 ppm or more. Electron microscopy also revealed marked increases in smooth endoplasmic reticulum in hepatocytes of the DEN plus 500 ppm group. Furthermore, induction of cytochrome P-450 (CYP) 1A1/2, 2B1/2 or 4A1 was observed in the DEN plus 100 ppm group, that of CYP 1A1/2 being most marked. A similar change in CYP 1A1/2 was seen in the DEN plus 10 ppm group. The numbers and areas of connexin 32 (Cx32)-positive spots per hepatocyte were also significantly decreased in a dose-dependent manner. Similar changes in liver weights, P-450 isozymes and Cx32 immunohistochemistry were already evident in the DEN plus 250 ppm group at wk 1. The number of placental form glutathione S-transferase positive single cells was significantly increased in the DEN-initiated groups treated with 250 ppm or more. The results therefore strongly suggest that oxfendazole exerts liver tumour promotion potential.

A six-month intravenous repeated dose toxicity study of tazobactam/piperacillin and tazobactam in dogs

Tazobactam (TAZ) is a newly developed beta-lactamase inhibitor. Tazobactam/Piperacillin (TAZ/PIPC) is a formulation consisting of TAZ and PIPC in a ratio of 1:4. A six-month intravenous repeated dose toxicity study of TAZ/PIPC and TAZ including a one-month recovery period were carried out using male and female dogs. The doses were 200, 400 and 800 mg/kg/day for TAZ/PIPC, and 40, 80 and 160 mg/kg/day for TAZ. The results were as follows. 1. No test article-related deaths occurred during the study period. No effects on clinical findings, body weight and food consumption were evident. 2. No test article-related changes were noted in hematological, serum biochemical and urinalysis evaluations, and opthalmological and electrocardiographic examinations. 3. There were no test article-related changes in macroscopic findings or organ weight. 4. The histopathological examination revealed deposition of marked PAS-positive aggregates in liver cells of dogs given 400 mg/kg/day or more of TAZ/PIPC and 80 mg/kg/day or more of TAZ. Electron micrographs of hepatocytes revealed glycogen granules to be accumulated in the cytoplasm, and an increase of smooth endoplasmic reticulum. 5. After a one-month recovery period, the histopathological changes had generally disappeared, suggesting that they were reversible. 6. From the histopathological changes of liver, the no-toxic dose levels for TAZ/PIPC and TAZ were 200 mg/kg/day and 40 mg/kg/day, respectively.

Effect of diabetes on the rat hepatic glucose-6-phosphatase system in endoplasmic reticulum subfractions

Diabetes-induced alterations in the activities of the components of the glucose-6-phosphatase system (i.e., the enzyme, the glucose-6-P translocase (T 1), and the phosphate translocase (T 2) were examined in smooth and rough subfractions of hepatic endoplasmic reticulum from streptozotocin-injected rats. A significant effect of diabetes on the maximal velocity of glucose-6-P hydrolysis by the enzyme was present in both endoplasmic reticulum subfractions (3.1-fold increase in rough endoplasmic reticulum; 3.8-fold increase in smooth endoplasmic reticulum). Based on latency values, diabetes did not result in a proportional increase in capacity of T 1 or T 2. In contrast to the control condition, the relationship between transport capacity and hydrolytic capacity was not significantly different in the two subfractions from diabetic animals. Elucidation of the effects of diabetes on the components of the glucose-6-phosphatase system associated with smooth and rough endoplasmic reticulum membranes enhances our understanding of the hepatic contribution to diabetic hyperglycemia.

Ultrastructural study of the effect of POLYCTFE on primate liver

Polychlorotrifluoroethylene (POLYCTFE) existing as oligomers of 3 and 4 units, is a candidate base stock for a nonflammable hydraulic fluid for advanced aircraft. POLYCTFE caused significant changes in the livers of rats after repeated inhalation exposure. Ultrastructural studies of the livers from rats exposed to vapors of POLYCTFE oligomers for 90-days revealed an increase in the number of peroxisomes, dose-dependent mitochondrial swelling and a dose-dependent increase in smooth endoplasmic reticulum. The objective of this study was to ultrastructurally examine hepatocytes from the livers of primates exposed to POLYCTFE and compare the exposed primate hepatocytes to those from rat livers, in order to determine the relevance of the effect of POLYCTFE on rat livers to human livers.Male rhesus monkeys weighing 8 to 10 kg were dosed by gavage daily for 15 days with 0.725.g/kg POLYCTFE. Four animals received POLYCTFE and 3 received a comparable amount of water.

The status of the corpus luteum during pregnancy in Miniopterus schreibersii (Chiroptera: Vespertilionidae) with emphasis on its role in developmental delay.

Developmental delay is correlated with torpor in the temperate zone bent-winged bat, Miniopterus schreibersii (latitude 37 degrees S) as a period of pre-implantation delay (delayed implantation) followed by a short post-implantation delay (delayed development). During this time, the number of steroidogenic organelles in luteal cytoplasm is greatly reduced compared with normal embryogenesis, and granular endoplasmic reticulum is prominent. Nidation, which occurs while the animals are hibernating, is not accompanied by marked changes in luteal ultrastructure, although the number of lipid droplets decreases somewhat. Progesterone rises slightly but not significantly; however, a pre-nidation decrease in high 17 beta-estradiol levels may play a role in implantation. Following implantation, the conceptus remains delayed at the blastocyst stage for several weeks. During this time the bats remain torpid and the only change in luteal cell ultrastructure is an increase in smooth endoplasmic reticulum as differentiation begins toward the trilaminar stage. At the end of developmental delay hypertrophy of the luteal cell begins and mitochondria and lipid droplets increase, markedly. By this time arousal from hibernation has occurred, placentation takes place and normal development is underway. At placentation, smooth endoplasmic reticulum reaches its maximum in luteal cytoplasm; estrogen and progesterone levels peak about 6 weeks later. For the remaining 2 months of gestation, signs of luteolysis appear. These observations suggest that the corpus luteum of developmental delay, though sub-optimally functional, is prolonged in its luteinization by the arrival of winter when the bats enter torpor. The capacity for maximal steroidogenesis is acquired at the end of winter, some weeks after implantation, when arousal occurs and normal development ensues.

In vitro stimulation and inhibition of steroid hormone release from postovulatory follicles of the tilapia, Oreochromis mossambicus

Postovulatory follicles of the tilapia, Oreochromis mossambicus, were incubated with graded doses of salmon gonadotropin to identify the steroid hormones released by this tissue. In addition, the effects of either cytochalasin B or colchicine on steroid hormone release were studied. After the incubation, the tissue was examined by electron microscopy. Postovulatory follicles released testosterone and estradiol-17B in a dose-dependent manner with gonadotropin. There was no detectable release of progesterone or 17a-OH-progesterone. When stimulated with high doses of gonadotropin, the steroidogenic cells showed an increase in smooth endoplasmic reticulum, Golgi complexes, and lipid droplets. Also, microfilaments became arranged in orderly bundles and were found close to the numerous secretory vesicles and lipid droplets. Upon incubation with gonadotropin and either colchicine or cytochalasin B, the cells still appeared steroidogenic, but the filaments were not organized nor associated with vesicles or lipid droplets. Release of steroid hormone decreased significantly. Also in these tissues, vesicles were no longer numerous in the apical region of the granulosa cells, but were located primarily near smooth endoplasmic reticulum and Golgi complexes. This suggests that disruption of the cytoskeleton results in reduced steroid hormone synthesis or release.

Catecholaminergic nerves in the embryonic chick ovary: co-localization with beta 2-adrenoceptor-bearing steroidogenic cells.

The present study investigates the innervation of the embryonic chick ovary with regard to (i) development and compartmentalization of catecholaminergic nerves, and (ii) presence of adrenoceptors on steroidogenic target cells of catecholaminergic nerve terminals. Catecholaminergic nerve fibers visualized by glyoxylic acid-induced histofluorescence first appeared at embryonic day (E) 13. From E15 through E21 the density of fluorescent aminergic nerves increased markedly in parallel with the concentration of catecholamines and numbers of nerve bundles and single axons seen at the electron-microscopic level. Catecholaminergic nerves were confined to the ovarian medulla and closely associated with interstitial cells. Nerve terminals approached interstitial cells up to a distance of 20 nm and, in their majority, exhibited uptake of the false adrenergic transmitter 5-hydroxydopamine. Although adrenaline amounted to 14% of the total catecholamine content at E21, adrenaline immunoreactivity was only detected in adrenal chromaffin cells, but not in nerve fibers or cell bodies within the ovary. Interstitial cells structurally matured between E15 and E21 as documented by an increase of smooth endoplasmic reticulum and tubular mitochondria. Monoclonal antibodies mAB 120 and BRK 2 raised against avian beta 1- and mammalian beta 2-adrenergic receptors revealed the presence of beta 2-adrenoceptor-like immunoreactivity on the surface of interstitial cells, but not on any other cell type. The results are consistent with the notion of a dense adrenergic innervation of the embryonic chick ovarian medulla and its steroidogenic interstitial cells, and suggest the chick ovary as an excellent model for elucidating the functional role of a neural input to steroidogenic cells during development.

Effects of p-tert-butylphenyl trans-4-guanidinomethylcyclohexane carboxylate hydrochloride (NCO-650) and its metabolite, p-tert-butylphenol(BP) on drug-metabolizing enzymes and fine structure in rat liver.

The effects of p-tert-butylphenyl trans-4-guanidinomethylcyclohexane carboxylate hydrochloride (NCO-650) and its metabolite, p-tert-butylphenol(BP), on the drug-metabolizing enzymes and fine structure in the rat liver were examined. Aminopyrine demethylase activity was inhibited by the administration of NCO-650 and BP at a dose of 2 and 10 mg/kg, p.o. The increases of microsomal cytochrome b5 and cytochrome P-450 contents were noticed at 1, 12 and 24 hr after NCO-650 and BP administration. Ascorbate-dependent lipid peroxidation of mitochondria and microsome increased by the administration of NCO-650 and BP, but NADPH-dependent lipid peroxidation decreased by these drugs. In the morphological observations of fine structure in the liver, NCO-650 and BP caused the swelling and decrease of rough endoplasmic reticulum and the increase of smooth endoplasmic reticulum. The morphological changes of liver fine structure were related to the changes of drug-metabolizing enzymes in the liver by the administration of NCO-650 and BP, which may be suggest the transitory and functional responses of these drugs in the liver. The effect of BP on the drug-metabolizing enzymes and fine structure in the liver was similar to that of NCO-650.

Effect of long-term inhibition of hydroxy-methylglutaryl coenzyme A reductase by mevinolin on the zona fasciculata of rat adrenal cortex. A combined morphometric and biochemical study.

The effects of a 7-day infusion with mevinolin, a potent competitive inhibitor of hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase, on the adrenal zona fasciculata were examined in normal and dexamethasone/ACTH-treated rats. In both groups of animals, the drug caused a lowering in plasma and intra-adrenal cholesterol concentrations, as well as a slight decrease in the blood level of corticosterone. Morphometry of zona fasciculata cells showed that specific mevinolin-induced changes (i.e. those occurring in both groups of rats and therefore not due to enhanced release of ACTH following decrease in circulating corticosterone) are severe lipid-droplet depletion and a conspicuous increase in smooth endoplasmic reticulum (SER) and peroxisomes. The hypothesis is discussed that these morphological changes express a compensatory response of zona fasciculata cells to counteract the mevinolin-induced inhibition of cholesterol synthesis in both liver and adrenal cortex.

Effect of p-tert-butylphenyl trans-4-guanidinomethyl cyclohexane carboxylate hydrochloride (NCO-650) on drug-metabolizing enzymes and fine structure in rat liver

The effects of p-tert-butylphenyl trans-4-guanidinomethyl cyclohexane carboxylate hydrochloride (NCO-650) on drug-metabolizing enzymes and fine structure in rat liver were investigated. Aminopyrine demethylase, cytochrome b5 and cytochrome P-450 contents increased by a single administration of NCO-650 (10, 100 and 1000 mg/kg, p. o.). NCO-650 caused the morphological changes of liver fine structure such as disarrangement of rough endoplasmic reticulum (rER), detachment of ribosome from the rER and increase in smooth endoplasmic reticulum. The increases in drug-metabolizing enzyme activities and morphological changes in rat liver by NCO-650 were not dose-dependently. Trimethadione metabolism was not accelerated by the administration of NCO-650. In those results, the morphological changes in liver by a single administration of NCO-650 seem to be a direct action on the membrane of hepatocytes and its organelle. The induction of drug-metabolizing enzyme contents by NCO-650 was suggested a transitory response with the morphological changes in the liver.