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D Wuppermann

Publications and source records attributed to D Wuppermann.

11 recordsLinked to original sources
PubMed1988

[Pharmacological characterization of the new highly potent beta-adrenergic receptor blocker soquinolol].

The present pharmacological test results characterize soquinolol (5-[3-tertiary butylamino-2-hydroxypropoxy]-2-formyl-1,2,3,4- tetrahydroisoquinoline mucate, We 704, Sertum) as a highly potent non-subtype-selective beta-adrenergic receptor blocker, which is devoid of any intrinsic sympathomimetic activity. Its localanaesthetic activity (membrane stabilizing effect) is very weak. It also shows good enteral efficacy and long duration of action. In binding studies with heart (Ki beta 1 = 3.25 nmol/l) and lung membranes (Ki beta 2 = 0.85 nmol/l) its binding profile was found to be similar to that of propranolol. Soquinolol inhibits the isoprenaline-induced tachycardia (EC50% = 48 micrograms/l) in the guinea-pig Langendorff heart in vitro to the same degree as propranolol. However, in the conscious dog soquinolol's beta 1-adrenergic blocking activity (ED 50%) on intravenous injection (5.5 micrograms/kg) and oral administration (5.8 micrograms/kg) is about twice as great as that of pindolol and 19 times (i.v.) or 138 times (p.o.) greater than that of propranolol. These results suggest 95% enteral efficacy for soquinolol (pindolol 88%, propranolol 13%). The differences in soquinolol's and propranolol's efficacy detected in vitro and in vivo are partially attributable to differences in their kinetic properties namely the lower protein binding and the higher distribution volume of soquinolol. In the conscious dog, soquinolol inhibits beta 1-(ED 50% = 4.0 micrograms/kg) and beta 2-receptors (ED 50% = 2.7 micrograms/kg) at dose levels which do not differ significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗
PubMed1976

Influence of D-penicillamine and beta-aminopropionitril on the metamorphosis of Rana temporaria.

Tadpoles of Rana temporaria (size 5-7 mm) were kept in solutions of D-penicillamine (DPA), beta-aminopropionitril (betaAPN), and L-thyroxine at different concentrations for 18 days. The influence of the substances on metamorphosis was investigated. In low concentrations (1 or 10 mg/100 ml) D-penicillamine accelerates the process of metamorphosis. At these concentrations investigated skeletal malformations could not be observed. A content of 100 mg of DPA/100 ml is toxic. After 8 days of exposure only 4 of the 15 test animals had survived. In all concentrations investigated, beta-aminopropionitril has a toxic action. In low concentration (1 mg/100 ml) deformities are found which could be described as bending of the femur and twisting of the whole hind limb. The animals are non-viable, they die shortly after termination of metamorphosis. Higher concentrations (10 or 100 mg/100 ml) are lethal within the first 10 days. L-thyroxine (0.01 mg/100 ml) shows the wellknown metamorphosis-accelerating effect.

Aminopropionitrile↗
PubMed1975

[Influence of concomitant treatment with D-penicillamine and beta-aminopropionitrile on mechanical properties of rat connective tissue (author's transl)].

In order to study the influence of D-penicillamine (DPA) and beta-aminopropionitrile (BAPN) as well as of a combination of both substances (proportion by weight 1:1) on the collagen of skin, aorta, and femoral epiphysial cartilage, the mechanical properties of these fibrous organs were examined, after having performed tests on onset and dissipation of action, measured by the decrease of ultimate load of excised strips of skin using the two individual compounds. The action of 320 mg/kg of DPA sets in within 7 days reaching a maximum value after 14 days. After discontinuance of the substance the control values are reached within 15 days. BAPN shows its maximal effect on the 18th test day. After discontinuance of treatment the control value is not reached within 35 days. DPA and BAPN show organo-specific actions: DPA has a considerably stronger influence on the collagen of skin than on the collagen of the aorta; under the present test conditions it does, however, not affect the collagen of the distal femoral epiphysial cartilage. As compared to DPA, BAPN exerts a less pronounced influence on the collagen of the skin, similar influence on the collagen of the aorta, and a strong influence on the collagen of the distal femoral epiphysial cartilage. If both substances are administered together, the organospecific actions of DPA on the one hand and BAPN on the other hand are maintained. It is discussed whether the different chemical compositions of the collagen (Type I--IV) may be connected with the organospecific effects of the test substances.

Aminopropionitrile↗
PubMed1975

[Effect of high dosis of D-penicillamine and paramethasone on mechanical properties of rat connective tissue (author's transl)].

Male albino rats are treated with high doses of D-penicillamine (2000 mg/kg/day orally), paramethasone (50 mu-g/kg/day orally), and with a combination of equal doses of D-penicillamine and paramethasone for a period of 4 weeks. At the end of treatment the mechanical properties of dorsal skin and aorta of the experimental animals are determined. 4 weeks of treatment with D-penicillamine or paramethasone, respectively, leads to a decrease in the skin thickness of the experimental animals. With simultaneous administration of both substances the decrease in skin thickness is about the same. Load resulting in rupture is considerably reduced by D-penicillamine, while only a slight decrease is seen with paramethasone. Simultaneous administration of both substances results in considerable decrease in load resulting in rupture, similar to the effect produced by D-penicillamine. Tensile strength which is not influenced by paramethasone treatment, decreases after treatment with D-penicillamine as well as after simultaneous administration of D-penicillamin and paramethasone. Load resulting in rupture of the aorta remains uninfluenced under the experimental conditions. Comparison of the groups shows that simultaneous administration of D-penicillamine and paramethasone leads to the same results as those which may be obtained with sole administration of D-penicillamine. This suggests that the effect of D-penicillamine on the mechanical properties of the rat skin is not influenced by an additional high dose of paramethasone under the experimental conditions chosen.

Animals↗
PubMedDate not supplied

[Animal experiments on the maintenance dose of D-penicillamine].

The question of a D-penicillamine maintenance dose was tested by the load resulting in rupture of excised strips of dorsal skin of male albino rats. The reduction in load resulting in rupture (-48.5 per cent) obtained by 14 days of treatment with 320 mg/kg/day orally can be maintained completely over a treatment period of 28 days by daily administration of half the dose (160 mg/kg/day orally). Animal experimental findings correspond well with the procedure applied in hospital, to fix the maintenance dose at 30-50 per cent of the maximal dose after full effect is reached.

Animals↗