Polish journal of pharmacology and pharmacy最新文献

The aim of this study was to explore whether ip administration of ascorbic acid (AA) in a dose of 500 mg/kg, once a day for 3 following days, affected the content of lipid peroxidation products: malondialdehyde (MDA) and conjugated dienes (CD) in organs of mice. Injection of AA caused 2.1-, 1.3- and 1.8-fold increase in the concentration of this vitamin in liver, spleen and lungs, respectively, while the content of MDA and CD in these organs did not differ from values found in animals treated with 0.9% NaCl. It suggests that in our animal model AA did not act as a prooxidant enhancing the lipid peroxidation in various tissues.

Oral dose of enalapril or captopril moderately reduced the blood pressure of the spontaneously hypertensive rats (SHR) but not those of normotensive rats. The single daily dose of captopril (30 mg/kg) produced antihypertensive response equivalent to enalapril (3 mg/kg). Chronic administration of these drugs for 2 weeks revealed that systolic blood pressure was reduced more by captopril than enalapril. We did not find differences in hypotensive activity between Enalapril IF and Renitec Merck as well as Captopril JZF Polfa and Capoten Squibb.

The paper presents the results of studies into the effects of single and repeated (2 or 10 mg/kg po, twice daily for 14 days) administration of imipramine (IMI) on the behavior of male Wistar rats in an acoustic startle response test. Statistically significant attenuation of the animal reactivity was observed after 8 or 14 days administration of IMI in a dose of 10 mg/kg. Apomorphine APO (1.0 mg/kg, ip) enhanced the animals reactivity after repeated (but not single) administration of IMI in a dose of 2 mg/kg. The obtained results confirm the hypothesis about an increase of the dopaminergic system reactivity under the influence of repeated administration of tricyclic antidepressants.

The influence of dopamine (DA) receptor blockers (haloperidol, sulpiride) on electric footshock-induced fighting behavior and on the effect of antidepressants (imipramine, clomipramine, nomifensine, mianserine) was investigated in chronically stressed male Wistar rats. Exploratory activity in an open field was measured in the same groups of animals. The effect of chronic stress and antidepressants on DA utilization in the brain was also investigated. It was shown that 48 h after the last session of repeated stress (various unpredictable stressors over 16 days) the number of fighting attacks was significantly reduced. However in stressed rats treated chronically (for 14 days) with antidepressants the intensity of fighting was restored to control value. On the contrary, when the stressed rats, receiving antidepressants chronically, were pretreated with DA receptor blockers: haloperidol (0.5 mg/kg) or sulpiride (50 mg/kg) but also alpha 1-adrenergic receptor blocker - prazosin (3 mg/kg) the effect of antidepressants was abolished. Exploratory activity was not significantly reduced under influence of stress. Neither antidepressants nor sulpiride modified exploratory activity of stressed rats. Haloperidol and prazosin but not sulpiride decreased this activity of normal, stressed and antidepressant-treated rats. It is concluded that prolonged treatment with antidepressants counteracts the decrease in aggression induced by chronic stress and that DA mechanism participate in this effect of antidepressant drugs.

2,4-Disubstituted 5-amino-6-pyrimidinecarboxylic acid derivatives 5-20 were synthesized and evaluated for their pharmacological activity. Compounds 11-14, 17-19 showed antiaggressive effect, compounds 5, 8, 9, 11, 12 and 19 displayed antiserotonin activity while compound 14 exerted antireserpine action.

The present study examined the effects of CGP 37849 and CGP 39551, competitive NMDA receptor antagonists, in the forced swimming test in rats and mice. Administered in a single dose or three times both examined compounds reduced the immobility time in rats. Active doses used in that test either did not change the locomotor activity or decreased it. A similar effect in both tests was shown by active (R)-enantiomers CGP 40116 and CGP 43487. Reduction of the immobility time induced by CGP 37849 and CGP 39551 in the forced swimming test in rats was antagonized by haloperidol and (+/-)-sulpiride, but not by SCH 23390 or prazosin. CGP 37849, but not CGP 39551, also reduced the immobility time in the forced swimming test in mice. The results obtained indicate that CGP 37849 and CGP 39551 induce an antidepressant-like effect in the forced swimming test, probably via an indirect dopamine activation resulting from blockade of NMDA receptors.

High affinity binding sites for adenosine were identified in rat kidney cortex basolateral membranes. Kinetic analysis indicates two sets of [3H]adenosine, [3H]ADO, binding sites, one with high affinity and Kd = 0.84 +/- 0.25 microM, one with low affinity and Kd = 4.74 +/- 0.37 microM. The ADO receptors were further characterized using ADO analogs as binding inhibitors. The most potent inhibitor of [3H]ADO binding was N-methyl-adenosine with a Kd of 5 microM, whereas 2-deoxyadenosine was about 50 times less potent. The binding of [3H]phenylisopropyladenosine, [3H]PIA, and [3H]-N-ethylcarboxamidoadenosine, [3H]NECA, to basolateral membranes was rapid and reversible. The Scatchard plot of [3H]PIA binding showed monophasic curves for experiments performed at 0 degrees C and 37 degrees C. The apparent Kd of [3H]PIA binding at 0 degrees C was 0.19 +/- 0.05 nM and 0.34 +/- 0.07 nM at 37 degrees C. The binding of [3H]NECA to basolateral membranes was found with an apparent affinity Kd of 110 +/- 50 nM at 0 degrees C. Pretreatment of membranes with N-ethylmaleimide (NEM) inhibited the [3H]PIA binding and did not affect the [3H]NECA binding. These results demonstrate that both A1 and A2 adenosine receptors are present in basolatertal membranes of rat kidney.

Low doses of apomorphine (20-50 micrograms/kg) induced an increase in the activity of an endogenous inhibitor of cAMP dependent protein Kinases (type I inhibitor) in the striatum, anterior and posterior hypothalamus of normotensive rats by stimulating D2-dopamine receptors. In contrast, high doses of the compound (2-10 mg/kg) produced a dose dependent decrease in type I inhibitor activity. In the posterior hypothalamus of vasopressin hypertensive rats and SHR the maximal increase of type I inhibitor activity was markedly higher than in normotensive animals. Moreover, apomorphine induced the increase of type I inhibitor activity in a much wider range of doses. Only as high dose of the compound as 10 mg/kg was able to decrease type I inhibitor activity. This points to a marked supersensitivity of D2 receptors and suggests the subsensitivity of D1 receptors in this brain area of hypertensive rats. In contrast, in the striatum and anterior hypothalamus of hypertensive rats the apomorphine dose response curves were similar to those in normotensive rats. Thus, it seems tha hypertension is associated with the alteration in sensitivity of D2 and D1 receptors in the posterior hypothalamus, the brain area involved in regulation of blood pressure.

Esters of N,N-diethylaminoacetic acid and hydroxyamines, obtained from structurally different natural monoterpenes, were pharmacologically examined. It was proved that salts of the obtained compounds had local anesthetic properties in infiltration anesthesia, compounds 9, 6 and 8 having been more potent than lidocaine. Compounds 7-9 slightly increased the arrhythmogenic dose, and compound 12 - the lethal dose of strophanthin. All the examined compounds transiently decreased the arterial blood pressure and displayed a cardiopressive activity.

In 2K,1C-RHR (two-kidney, one-clip hypertensive rats) serotonergic mechanisms in blood platelets were studied. The endogenous serotonin (5-HT) concentration in whole blood and in platelets remained unchanged in relation to the sham operated rats. Also the uptake of labelled 5-HT in rats with renal hypertension was not altered. However platelets aggregability was increased in 2K,1C-RHR. Acute administration of captopril (10 mg/kg and 100 mg/kg po) diminished blood pressure but did not change either the concentration of 5-HT in whole blood and in platelets of hypertensive rats or the uptake of this amine. Platelets aggregation and the amplifying effect of 5-HT in hypertensive rats were also unchanged after acute captopril administration. Similar results were observed after its administration in a dose of 30 mg/kg for one week. Our results indicate that captopril did not affect the platelets serotonergic mechanisms in 2K,1C-RHR.