Inhibitory effect of activated protein C on platelet aggregation induced by the prothrombin-converting reaction.

The present study was undertaken to elucidate the effect on platelet aggregation of the prothrombin-converting reaction on platelets with or without activated protein C (APC). A reaction mixture of washed platelets from human individuals, Factor Xa and prothrombin markedly induced platelet aggregation; maximum aggregation rates, 31.3-92.

Antihypertensive effect of the new calcium antagonist (+-)-3-(benzylmethylamino)-2,2-dimethylpropyl-methyl-4-(2-fluoro-5- nitrophenyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylate hydrochloride in rats.

The antihypertensive effect of TC-81 ((+-)-3-(benzylmethylamino)-2,2-dimethylpropyl-methyl-4-(2-f luoro-5- nitrophenyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylate hydrochloride), a new calcium antagonist, was investigated in normotensive and hypertensive rats. By oral administration, the antihypertensive activity of TC-81 (ED20% in spontaneous hypertensive rats (SHR), DOCA-salt hypertensive rats and renal hypertensive rats were 0.37, 0.

Effect of TC-81, a new dihydropyridine derivative, on K(+)-induced contraction in rat aorta.

TC-81 (3-(N-benzyl-N-methylamino)-2,2-dimethylpropyl methyl-2,6-dimethyl-4-(2-fluoro-5-nitrophenyl)-1,4-dihydro-pyridine- 3,5-dicarboxylate hydrochloride) is a new dihydropyridine derivative. The effects of TC-81 (10(-10)-10(-8) M) on high K(+)-induced contractions were investigated in isolated rat aorta, and the results were compared with those obtained with nicardipine, nifedipine, diltiazem and papaverine. All drugs produced concentration-dependent relaxation of K(+)-induced contractions.

Effect of clenbuterol on contractile response in periurethral striated muscle of rabbits.

The effect of clenbuterol, a selective beta 2-adrenoceptor agonist, on isolated periurethral striated muscle preparations from rabbits has been investigated. The periurethral striated muscle produced a contraction in response to field stimulation. An application of clenbuterol resulted in a dose-dependent potentiation of the field stimulation-induced contraction.

Characterization of immunomodulating action of TI-31 on antibody response in mice.

TI-31, at concentrations of 10 and 100 microM, suppressed the antibody response to T cell-dependent (sheep red blood cells, SRBC) and -independent antigens (trinitrophenyl-lipopolysaccharide, TNP-LPS and TNP-Ficoll). The anti-SRBC response was suppressed by TI-31 when T cells were replaced by a supernatant of concanavalin A (Con A)-stimulated spleen cells, indicating the drug had influence on T lymphocytes, B lymphocytes and macrophages. TI-31 augmented the Con A-induced suppressor T cell (Ts) assessed by anti-SRBC plaque-forming cells response in vitro.

Protective effect of vitamin D3 analogues on endotoxin shock in mice.

The effect of vitamin D3 analogues on endotoxin shock in mice was investigated. Male ICR mice were orally administered vitamin D3 analogues or vehicle, accompanied by an intraperitoneal injection of endotoxin (E. Coli lipopolysaccharide, LPS, 20 mg/kg).