tretinoin and methyl-retinoate

To determine whether beta-carotene (beta-C) can serve as a source of intestinally-derived retinoic acid (RA), either 15,15'-[14C]beta-C or unlabeled beta-C was perfused through 30 cm jejunal segments of ferrets in vivo. Portal vein blood was sampled periodically via an indwelling catheter. RA was identified in portal blood by comparing retention times in HPLC, by UV absorption, and by derivatization (methylation) and subsequent GC-MS analysis. The RA concentration in the portal blood increased 3-fold with perfusion of beta-C (P < 0.05), and remained at 18 nmol/L during the perfusion of beta-C. The single peak of RA in HPLC was shown to consist of four separate peaks by GC-MS, which may be cis-trans isomers of RA. The concentration of RA in portal blood returned to the initial level (5 nmol/L) after a 2 h period of intestinal perfusion with 5% dextrose. Retinyl ester concentration in portal blood did not change before or after the perfusion, whereas retinol decreased significantly during the perfusion of beta-C. This study clearly indicates that a considerable quantity and number of polar metabolites, including RA, are formed from beta-C in the ferret intestine which are transported via the portal vein to the liver.

Topics: Animals; beta Carotene; Carotenoids; Ferrets; Intestinal Mucosa; Intestines; Models, Biological; Portal Vein; Tretinoin

Topics: Gas Chromatography-Mass Spectrometry; Humans; Methylation; Tretinoin

The influence of all-trans- and 13-cys-methylretinoate on antibacterial and antiviral immunity was studied in experiments on noninbred C57Bl/6 and (CBA X C57Bl/6) F1 mice. All-trans-methylretinoate was shown to stimulate the production of antibodies to E. coli antigens, with the effect being dose-dependent. At the same time both compounds inhibited the production of inhibitors, interferon and antibodies to influenza virus.

Topics: Animals; Antibodies, Bacterial; Antibodies, Viral; Antibody Formation; Antiviral Agents; Diterpenes; Escherichia coli; Female; Interferons; Male; Mice; Orthomyxoviridae; Retinyl Esters; Tretinoin; Vitamin A

The influence of retinyl acetate, retinoic acid and its esterified cis- and trans-derivatives, retinoids C15 and C20 on erythrocytes, liver macrophages and white pulp of the spleen was studied in the experiments on mice of different strains. It was found that administration of these compounds leads to the damage of the blood cells, increase in the number of liver macrophages and the share of white pulp in the spleen and stimulation of the local response to tuberculin. The interdependence of changes in the blood and adjuvant is suggested.

Topics: Adjuvants, Immunologic; Animals; Diterpenes; Erythrocytes; Female; Liver; Macrophages; Male; Mice; Mice, Inbred CBA; Retinoids; Retinyl Esters; Spleen; Tretinoin; Vitamin A

It has been shown in experiments on Wistar male rats with the use of light and electron microscopy and morphometry that a single intraperitoneal injection of high doses of all-trans-methylretinoate and methyl-7,8- dihydroretinoate leads to an increase in the spleen weight, the appearance in the spleen of red cells changed in the shape, activation of phagocytic intensity of macrophages, intercellular interaction, lymphocyte proliferation and formation of new lymph follicles.

Topics: Animals; Erythrocytes; Injections, Intraperitoneal; Lymphocytes; Male; Mitosis; Organ Size; Phagocytosis; Rats; Rats, Inbred Strains; Spleen; Tretinoin

Topics: Animals; Appendectomy; Appendix; Female; Lymph Nodes; Lymphocytes; Macrophages; Neoplasms, Experimental; Rats; Rats, Inbred Strains; Spleen; Thymus Gland; Tretinoin

It has been shown that all-trans-methylretinoate, 13-cis-methyl retinoate and retinoid C15 administered intraperitoneally in the form of 0.05% solutions in excess doses reduce the red cell count, hemoglobin content, and osmotic resistance of red cells in C57Bl/6 mice. Administration of 13-cis-methylretinoate and retinoid C15 resulted in the increase of the number of cells uncapable to stain with paraldehyde fuchsin. Anemia induced by all-trans-methylretinoate in AKR mice was accompanied by erythropoiesis enhancement in the bone marrow.

Topics: Anemia; Animals; Erythrocyte Count; Erythrocytes; Hemoglobins; Mice; Mice, Inbred AKR; Mice, Inbred C57BL; Time Factors; Tretinoin; Vitamin A

The photoisomerization of methyl all-trans-retinoate is dependent upon both solvent polarity and irradiation time. The all-trans-isomer isomerizes most rapidly in solvents of high polarity. Methyl 11-cis-retinoate is maximally produced after three hours in dimethyl sulfoxide, while it is not formed to an appreciable extent in heptane. Methyl 13-cis-retinoate forms maximally after two hours in heptane, then decrease in concentration by one-half to about the same level maximally formed in dimethyl sulfoxide. The solvent and time dependences of the other isomers are presented to allow selection of conditions for maximal production of desired isomers. The results for methyl retinoate appear applicable for retinoic acid.

Topics: Chemistry, Organic; Isomerism; Kinetics; Organic Chemistry Phenomena; Solvents; Tretinoin

The major metabolite in rat bile of injected C(14)-retinoic acid was purified by ion-exchange and silicic acid chromatography; it has the spectrum of methyl retinoate, releases retinoic acid upon basic hydrolysis or by treatment with beta-glucuronidase, and contains glucuronic acid. The metabolite was characterized by treatment with diazomethane followed by hexamethyl-disilazane, or with periodate followed by semicarbazide, and the products were chromatographed. The metabolite has been tentatively identified as retinoyl beta-glucuronide.

Topics: Bile; Chromatography; Enzyme Inhibitors; Glucuronates; Glucuronic Acid; Glucuronidase; Lactones; Metabolism; Phenolphthaleins; Rats; Research; Tretinoin; Vitamin A