The foot of the desert snail, Eremina ehrenbergi, is supplied by branches of the pedal nerves which enter a coarse-meshed peripheral neural plexus. Light and electron microscopic preparations revealed the presence of ganglionic knots embedded in the foot musculature. In these knots the neural cell bodies are found to be situated on the periphery of neuropile. Cross sections through the neuropile demonstrate the presence of many synaptic junctions of the axo-axonic type. In some axon profiles light and dense synaptic vesicles are observed. Some of the axons which constitute the terminal plexus enter into close apposition with muscle cells and definite areas where synaptic transmission in thought to occur are well observed. On the basis of these results it can be concluded that the neural plexus may be involved in the production of the patterned pedal activity in Eremina ehrenbergi.
- MeSH
- ganglia bezobratlých ultrastruktura MeSH
- hlemýždi anatomie a histologie MeSH
- nervosvalové spojení fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The ribosomal RNA (rRNA) synthesis in the proerythroblasts and hepatocytes of the chick embryo was examined using the nucleolar test during embryonic days 5-10 after intraamniotic administration of single doses of cyclosporin A (CsA). Administration of the 0.75 or 7.5 g of CsA 5th day of embryonic development caused a significant decrease in proerythroblasts and hepatocytes numbers with active rRNA synthesis. Five days after the CsA administration, the percentage of proerythroblasts with biosynthetically active nucleoli already did not differ from the control while the decreased numbers of hepatocytes actively synthetizing rRNA remained statistically significant. Our results indicate, that CsA inhibits the rRNA biosynthesis in embryonic immature cells. Depending on the cell type, the effect of CsA and its dynamics may be apparently different.
- MeSH
- cyklosporin farmakologie MeSH
- erytroblasty účinky léků metabolismus MeSH
- játra anatomie a histologie účinky léků metabolismus MeSH
- kuřecí embryo cytologie účinky léků metabolismus MeSH
- RNA ribozomální biosyntéza MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo cytologie účinky léků metabolismus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- cyklosporin MeSH
- RNA ribozomální MeSH
Effects of oxacillin administered to pregnant or nursing randombred NMRI mice on the humoral immune response of their offspring were studied. The primary humoral response of male offspring to immunization by sheep red blood cells (SRBC) on the 24th postnatal day was assayed. Spectrophotometric determination of SRBC lysis by anti-SRBC IgM antibodies produced by spleen cells was used. Treatment of pregnant mice with oxacillin (70 mg/kg body weight) from the 12th to 16th day of pregnancy resulted in an enhancement of the spleen IgM antibody response in their offspring. The same treatment of nursing mothers, either on postnatal days 1-4 or 13-16, depressed the humoral response of the offspring. When the litters of control mothers and mothers treated with oxacillin from the 11th to 15th day of pregnancy were cross-fostered at birth, the offspring born of saline-treated mothers and nursed by oxacillin-treated mothers as well as the offspring born to oxacillin-treated mothers and nursed by control mothers produced significantly higher amounts of spleen anti-SRBC IgM than the control offspring. The results suggest that the alteration of the immune response in offspring of mice treated by oxacillin during pregnancy was induced not only in the prenatal period, but also postnatally by factors originating from effects of oxacillin on the maternal organism.
- MeSH
- myši MeSH
- oxacilin farmakologie MeSH
- těhotenství MeSH
- tvorba protilátek účinky léků MeSH
- zpožděný efekt prenatální expozice * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- oxacilin MeSH
Four-day administration of actinomycin D to the albino rat in daily doses of 25 micrograms/kg decreased--in relation to all blood cells of the bone marrow--the values of the more mature stages of the megakaryocytic line, i.e. megakaryocytes and naked megakaryocyte nuclei. The number of megakaryoblasts was not influenced.
- MeSH
- daktinomycin farmakologie MeSH
- krysa rodu Rattus MeSH
- megakaryocyty cytologie účinky léků MeSH
- počet buněk MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- daktinomycin MeSH
Daily administration of caffeine (30 or 60 mg/kg) to mature male rabbits for four consecutive weeks caused an increase in the plasma follicle stimulating hormone (FSH) and a decrease in the luteinizing hormone (LH). Testosterone was increased with the higher dose only while adrenocorticotrophic hormone (ACTH) was not altered by either one. These results suggest that the effects of caffeine on the two gonadotrophic hormones, FSH and LH, involve two separate pathways. The light microscope study revealed reduced sizes of the seminiferous tubules, inhibited spermatogenesis, fatty degeneration of the liver and hepatic lesions. The adrenal glands exhibited signs of stimulated steroidogenesis. It is concluded that long term intake of caffeine induces suppression of spermatogenesis mainly through inhibition of FSH release and this effect is maintained even in the presence of normal or high levels of testosterone and LH.
- MeSH
- časové faktory MeSH
- hormony fyziologie MeSH
- kofein farmakologie MeSH
- králíci anatomie a histologie fyziologie MeSH
- kůra nadledvin účinky léků MeSH
- systém hypofýza - nadledviny účinky léků MeSH
- testis účinky léků MeSH
- zvířata MeSH
- Check Tag
- králíci anatomie a histologie fyziologie MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- hormony MeSH
- kofein MeSH
The effect of cadmium chloride on the pituitary ACTH cells, gonadotropin- and thyrotropin-secreting cells, thyroid gland and gonads of the catfish, Clarias batrachus was investigated. Exposure to cadmium chloride caused a significant increase in the ACTH cell nuclear indices at day 7, 14 and 28, whereas the thyrotropin- and gonadotropin-secreting cells showed inactivation and accumulation of secretary products. The epithelial height of the thyroid follicles was also significantly reduced (P < 0.001) as compared to that of the untreated control fish. In experimental female fish, the gonosomatic index had undergone a significant reduction at all intervals studied (day 7, 14 and 28). However, in the male catfish a significant reduction in the gonosomatic index was observed only after exposure for 28 days. Ovarian maturation seems to have become arrested at perinucleolar stage and spermatogenesis at spermatocyte stage. The possible involvement of the hypothalamo-hypophyseal system in gonadal regression was discussed.
- MeSH
- chemické látky znečišťující vodu škodlivé účinky MeSH
- chlorid kademnatý MeSH
- chloridy škodlivé účinky MeSH
- gonády účinky léků MeSH
- hypofýza účinky léků MeSH
- kadmium škodlivé účinky MeSH
- štítná žláza účinky léků MeSH
- sumci anatomie a histologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chemické látky znečišťující vodu MeSH
- chlorid kademnatý MeSH
- chloridy MeSH
- kadmium MeSH
Using the Chick Embrotoxicity Screening Test (CHEST), two samples of bilirubin of different commercial origin were tested on 2, 3 and 4- day old chick embryos. Water soluble Bilirubin Lachema (containing 20 mg albumin per 1 ml) had no teratogenic effect. On the opposite, Bilirubin Merck (containing 8 mg albumin per 1 ml) manifested an apparent teratogenic potential when single doses 0.2 and 0.6 micrograms were administered intraamniotically on day 4. Dose-dependent malformations of brain and eyes, cleft beak and reduction deformities of limbs were observed. No such effects could be produced by administration of Bilirubin Merck on either day 2 and 3. A tentative explanation of the difference between teratogenic properties of Merck and Lachema bilirubin preparations may be sougth in the different proportion of the free and albumin bound fractions.
- MeSH
- abnormality vyvolané léky etiologie MeSH
- bilirubin toxicita MeSH
- kuřecí embryo účinky léků MeSH
- preklinické hodnocení léčiv metody MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo účinky léků MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- bilirubin MeSH
Three and four-day-old chick embryos were exposed to thalidomide as well as to its hydrolysis products before and after in vitro biotrasformation of these compounds with rat liver homogenate. Significant embryotoxic effects of 30 and 100 micrograms doses per embryo encountered only in the case when the products of alkaline hydrolysis of thalidomide were pretreated with rat liver homogenate.
- MeSH
- biotransformace MeSH
- hydrolýza MeSH
- játra metabolismus MeSH
- krysa rodu Rattus MeSH
- kuřecí embryo účinky léků MeSH
- potkani Wistar MeSH
- testy toxicity MeSH
- thalidomid metabolismus toxicita MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- kuřecí embryo účinky léků MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- thalidomid MeSH
