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K H Chemnitius

Publications and source records attributed to K H Chemnitius.

At least 19 recordsLinked to original sources
PubMed1986

Influence of new estrogens on liver transport function in rats.

Ethinylestradiol (EE), administered to male Wistar rats for 5 or 14 days, decreased bile flow and biliary excretion of ICG in bile fistula rats in dependence on dose. The bile acid excretion rate was not constantly influenced. EE pretreatment of rats also diminished the in vitro accumulation of eosine in liver slices. The new estrogens STS 651 and STS 661 decreased bile flow, ICG excretion and in vitro eosine accumulation to nearly the same extent as did EE pretreatment; bile acid excretion was not influenced significantly. Evidently the 14 alpha-15 alpha-methylen structure in STS 651 and STS 661 as well as the additional methoxygroup in C3 position did not protect against cholestatic effects of estrogens. The new 17 beta-trimethyl-silyloxy-estrogen J 303 did not show cholestatic effects in rats. This structure is able to prevent the formation of toxic estrogen metabolites in rats.

Animals↗
PubMed1986

[Comparison of the action of Cordemcura on selected cardiovascular parameters following intraduodenal and intravenous application in beagles].

The novel cardiotonic Cordemcura was tested for its cardiovascular effects after intraduodenal application to anaesthetized dogs. For this purpose, beagles received Cordemcura intraduodenally as a Tylose suspension, with 4 bolus injections (10(-5), 3 X 10(-5), 6 X 10(-5), and 10(-4) mol/kg) given at 30-min intervals. The test parameters used to analyze the onset of action and its course include: heart frequency (HFR), maximum rate of pressure rise (dp/dtmax) and decline (dp/dtmin) in the left ventricle, cardiac output (CO), stroke volume (SV), total peripheral resistance (TPR) and peripheral arterial blood pressure, systolic (Ps) and diastolic (Pd), and dose-effect curves determined for the individual test parameters. There was a dose-dependent increase of dp/dtmax up to a maximum of 130%, which 3 h afterwards was still about 60% above the initial value. The heart frequency, too, rose dose-dependently by a maximum of 80%, though not being significantly different from the initial value any longer 3 h after the last bolus injection. The Ps was slightly, but significantly decreased with the higher dose levels used. The influence on dp/dtmin and Pd was insignificant. A significant rise was found in the cardiac output, whereas the peripheral resistance showed a slight decline. After 3 h, a significant rise was still seen in the contractility (dp/dtmax), whereas the other parameters were no longer significantly different from the initial values. Moreover, selected dose levels of Cordemcura were tested after i. v. application, and a comparison was made of their effect on heart frequency, peripheral blood pressure, and inotropism. The importance of the findings was discussed.

Aminopyridines↗
PubMed1986

[Comparison of the cardiovascular actions of Cordemcura, isoprenaline and dobutamine in cats].

A comparative study was made of the closed-chest cardiovascular effects of Cordemcura (amrinone), isoprenaline, and dobutamine in anaesthetized cats (n = 17). The haemodynamic parameters used for this purpose include: maximum rate of both left ventricular pressure rise (dp/dtmax) and decline (dp/dtmin), heart frequency (HFR), arterial blood pressure, both systolic (Ps) and diastolic (Pd). The maximum changes of the haemodynamic parameters after increasing iv. bolus injections of the test substances were used to plot the dose-effect curves of the single parameters for each substance. All the 3 pharmaceuticals caused dp/dtmax to rise, with quantitative differences being found. Moreover, quantitatively different positive chronotropic effects have been found. The influence on the remaining haemodynamic parameters was different both in the quantitative and in the qualitative sense. The results were discussed with regard to comparing the cardiovascular effects of Cordemcura with isoprenaline and dobutamine.

Aminopyridines↗
PubMed1984

Pharmacokinetics of ethynyl estradiolsulfonate in minipigs.

The pharmacokinetics of ethynyl estradiolsulfonate labelled with 3H in the steroid nucleus and with 14C in the isopropylsulfonic acid side chain was investigated in male minipigs. The plasma level after intravenous administration was interpreted according to a three-compartment model. After oral administration the first two phases were overlapped by the absorption period. The renal and fecal excretion of the two labellings were investigated. In urine the majority of the 3H-labelled steroid was excreted in the unconjugated and in the glucuronide fractions. More than 70% of 14C in urine was unextractable.

Administration, Oral↗
PubMed1984

[Comparison of the pharmacokinetic behavior of Turivital, Acesal and Micristin].

The 3 acetylsalicylic acid preparations showed at normal patients at the same elimination phase no significant differences concerning the bioavailability (comparison of the area under the concentration-time-curve). The absorption kinetics of the preparations were different: the time up to the maximum serum concentration was at Turivital with 1,3 +/- 0,7 h and Micristin (2,1 +/- 0,8 h) the shortest, because the resorption delay was at Turivital the smallest. Absorption constant, fictive initial concentration and maximum concentration in serum are nearly the same in all 3 preparations.

Adult↗
PubMed1983

Liver neoplasms after long-term steroid application in rats.

Long-term ingestion of 5 mg/kg body weight ethinylestradiol per esophageal tube induces preneoplasms in the liver of Albino-Wistar-rats. The hepatocellular proliferations could be observed after a test period of 19.5 to 24.5 months. There was no sex difference.

Adrenal Gland Neoplasms↗
PubMed1983

Inhibition of male fertility by STS 557.

To ascertain the effects of STS 557 (17 alpha-cyanomethyl-17 beta-hydroxy-estra-4, 9-dien-3-one) on the reproductive and endocrine functions, male rabbits were given the substance orally daily over 8 weeks. In doses of 10 and 20 mg STS 557 per animal per day fertility inhibition was accompanied by a decrease of spermatogenesis and sexual activity. At the chosen dose of 5 mg per day, STS 557 caused a decrease of sperm motility, semen fructose content and sterility of the bucks. On the other hand, libido, semen volume, sperm number, sialic acid content in semen, serum LH and testosterone remained unaffected. Concomitant injection of testosterone did not reverse the suppressive effect of STS 557 on fertility. Motility of human sperm was lowered markedly by STS 557 in vitro. The human sperm penetration and pronuclear formation were significantly reduced in the vitro fertilization assay with zona-free hamster eggs. Findings are discussed in view of the development of male contraceptives.

Animals↗
PubMed1983

Studies on pharmacokinetics of STS 557 in animal species and man.

Following oral and i.v. administration of [14 alpha, 15 alpha-3H]-STS 557 to beagle dogs, baboons, rats and female volunteers, plasma level courses of total radioactivity and STS 557, and radioactivity excretion in urine and feces have been investigated. Bioavailability of orally administered STS 557 was found to be 80--90% in man and beagle dog, 70--80% in baboon and rat. Concerning the systemic availability following oral administration of equivalent doses, the following order was established: beagle dog greater than man greater than baboon greater than rat. Equilibrium dialysis indicates species differences in plasma protein binding and a considerable part of STS 557 to be present in plasma unbound. STS 557 is rather rapidly eliminated from the plasma compartment of all species investigated with half lives less than or equal to 10 h. As an additional time parameter of pharmacokinetics the "mean residence time" was used. Urinary excretion of STS 557 metabolites is dominant in all species, including the rat. In contrast to the great part of STS 557 in plasma total radioactivity, only small amounts of unchanged STS 557 are excreted in urine. First results of current studies in rabbits are presented, too.

Animals↗
PubMed1983

Long term toxicological studies on the progestin STS 557.

The toxicity of 17 alpha-cyanomethyl-17 beta-hydroxy-estra-4, 9-dien-3-one (STS 557) was studied by its oral administration of 0.1, 1.0 or 10.0 mg/kg/day to Wistar rats for six months, and of 0.01, 0.1 or 1.0 mg/kg/day to beagle dogs for six months, respectively. Levonorgestrel at a dose of 1.0 mg/kg/day was used as the standard in the dog study. With respect to the progestational activity of the compound the main target organs were the hypophysis, the reproductive organs and the adrenals. Mammary hyperplasia was observed in dogs treated with STS 557 or levonorgestrel at the dose of 1.0 mg/kg/day, but in no case mammary nodules could be detected. At the dose of 1.0 mg/kg/day STS 557 and levonorgestrel were found to increase the plasma insulin response to i.v. glucose in bitches, but neither the mean blood glucose levels nor the glucose utilization were affected. Moreover, during administration of both steroids to dogs temporary changes in serum concentrations of triglycerides and total cholesterol were noted. The results obtained in rats and dogs from functional and morphological investigations did not reveal any toxic side effects of STS 557 on the liver, the kidneys, the bone marrow or on blood coagulation. The effects on the reproductive organs observed following STS 557 especially in dogs are related to both the hormonal effects of the compound and the specific response of the dog to potent progestagens.

Animals↗
PubMed1980

Lysozyme (muramidase) and hemolytic complement (CH50U) in sera of beagle dogs and minipigs after longterm application of different preparations of estrogens and gestagens.

In studies for the chronic toxicity of estrogens and gestagens, lysozyme and hemolytic complement (CH50U) in sera of beagle dogs and minipigs were measured. Various doses of the sexsteroids were given: 0.01 mg, 0.1 mg and 1.0 mg/kg respectively. The influence of the steroids on the tested parameters after an application for 6 months was not significant, only in a single series with unphysiologically, high dosages of the preparations were some values changed significantly.

Animals↗
PubMed1976

[Endocrinologic and pharmacologic-toxicologic findings with ethinyl-estradiol sulfonate. 8th communication. Complement and lysozyme in the serum of beagles after 6 months application of ethinylestradiol sulfonate].

In course of studies for the chronic toxicity of estrogens after oral application two parameters of the unspecific resistance - complement (CH50U and CB50U) and lysozyme - in sera of 30 beagle-dogs were studied. The doses of the daily (over 6 months) applicated hormones were 1,0 mg/kg ethinylöstradiol and 1,0, 0,1 and 0,01 mg/kg ethinylöstradiolsulfonate (depotform). In the majority of all measurements no significant variations of serum complement and -lysozyme could be detected, however after application of high doses of the hormone ethinylöstradiol a little reduction of complement and significant elevations of lysozyme were observed.

Animals↗