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Serotonin (5-HT) and adrenaline acting at platelet 5-HT 2A -serotoninergic and α 2 -adrenergic receptors are involved in platelet aggregation. We have evaluated the antagonistic potency at 5-HT 2A , α 2A -, and α 2B -adrenoceptors as well as an anti-aggregation effect of aroxyalkyl derivatives of 2-methoxyphenylpiperazine and compared them with ketanserin, sarpogrelate, prazosin, yohimbine and ARC239 (2-[2-[4-(o-methoxyphenyl)-piperazin-1-yl]-ethyl]-4,4-dimethyl-1,3-(2H,4H)-isoquinolindione). Functional bioassays at cells expressing human receptors, revealed studied compounds to be moderate antagonists of 5-HT 2A and α 2 -adrenoceptors, with around 2-7 times stronger antagonistic effect at α 2B subtype than α 2A subtype. Further, studied compounds inhibited 5-HT 2A -mediated contraction in isolated rat aortic rings and 5-HT vasopressor response in rat in vivo. Studied compounds inhibited collagen stimulated whole rat blood aggregation with compound MH-77 (1-[(2,3-dimethylphenoxy)propyl]-4-(2-methoxyphenyl)piperazine hydrochloride) being more potent than sarpogrelate or yohimbine. They also inhibited 5-HT/adrenaline-, amplified ADP- or collagen- induced platelet aggregation. Simultaneous, moderate blockade of 5-HT 2A serotonin and α 2 -adrenergic receptors is effective in preventing aggregation and could constitute alternative antiplatelet therapy., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Unlabelled: Obesity affects an increasing number of individuals in the human population and significant importance is attached to research leading to the discovery of drug which would effectively reduce weight. The search for new drugs with anorectic activity and acting within the adrenergic system has attracted the interest of researchers. This study concerns the experimental effects on body weight of α2-adrenoceptor antagonists from the group of pyrrolidin-2-one derivatives in rats with diet-induced obesity., Methods: The intrinsic activity of the test compounds at the α-adrenoreceptors was tested. Obesity in rats was obtained by the use of fatty diet and then the influence of the test compounds on body weight, food and water intakes, lipid and glucose profiles and glycerol and cortisol levels were determinated. The effects of the compounds on locomotor activity, body temperature, blood pressure and heart rate were tested., Results: One of the test compounds (1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one) reduces the animal's body weight and the amount of peritoneal adipose tissue during chronic administration, at the same time it does not cause significant adverse effects on the cardiovascular system. This compound decreases temperature and elevates glycerol levels and does not change the locomotor activity and cortisol level at anti-obese dose., Conclusions: Some derivatives of pyrrolidin-2-one that act as antagonists of the α2-adrenoreceptor may reduce body weight. Reducing body weight for 1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one can be associated with decrease in food intake, body fat reduction, reduction of blood glucose, and increased thermogenesis and lipolysis. This effect cannot be the result of changes in spontaneous activity or stress., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Xanthone derivatives have been shown to posses many biological properties. Some of them act within the central nervous system and show neuroprotective or antidepressant-like properties. Taking this into account we investigated antidepressant-like activity in mice and the possible mechanism of action of 6-methoxy-2-[4-(2-methoxyphenyl)piperazin-1-yl]-9H-xanthen-9-one (HBK-11) - a new xanthone derivative. We demonstrated that HBK-11 produced antidepressant-like effects in the forced swim test and tail suspension test, comparable to that of venlafaxine. The combined treatment with sub-effective doses of HBK-11 and fluoxetine (but not reboxetine or bupropion) significantly reduced the immobility in the forced swim test. Moreover, the antidepressant-like activity of HBK-11 in the aforementioned test was blocked by p-chlorophenylalanine, and significantly reduced by serotonergic 5HT1A receptor antagonist - WAY-1006335 and 5HT2A/C receptor antagonist - ritanserin. As none of the above treatments influenced the spontaneous locomotor activity, it can be concluded that HBK-11 mediates its activity through a serotonergic system, and its antidepressant-like effect involves 5HT1A and 5HT2A/C receptor activation. Furthermore, at antidepressant-like doses HBK-11 did not cause the mice to display locomotor deficits in rotarod or chimney tests. Considering the pharmacokinetic profile, HBK-11 demonstrated rapid absorption after i.p. administration, high clearance value, short terminal half-life, very high volume of distribution and incomplete bioavailability. The compound studied had good penetration into the brain tissue of mice. Since studied xanthone derivative seems to present interesting, untypical mechanism of antidepressant-like action i.e. 5HT2A/C receptor activation, it may have a potential in the treatment of depressive disorders, and surely requires further studies., (Copyright © 2015 Elsevier B.V. All rights reserved.)