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BackgroundBlood platelets play an essential role in hemostasis, thrombosis and coagulation of blood. Beyond these classic functions their involvement in inflammatory, neoplastic and immune processes was also investigated. It is well known, that platelets have an armament of soluble molecules, factors, mediators, chemokines, cytokines and neurotransmitters in their granules, and have multiple adhesion molecules and receptors on their surface.MethodsSelected relevant literature and own views and experiences as clinical observations have been used.ResultsConsidering that platelets are indispensable in numerous homeostatic endocrine functions, it is reasonable to suppose that a platelet-associated regulatory system (PARS) may exist; internal or external triggers and/or stimuli may complement and connect regulatory pathways aimed towards target tissues and/or cells. The signal (PAF, or other tissue/cell specific factors) comes from the stimulated (by the e.g., hypophyseal hormones, bacteria, external factors, etc.) organs or cells, and activates platelets. Platelet activation means their aggregation, sludge formation, furthermore the release of the for-mentioned biologically very powerful factors, which can locally amplify and deepen the tissue specific cell reactions. If this process is impaired or inhibited for any reason, the specifically stimulated organ shows hypofunction. When PARS is upregulated, organ hyperfunction may occur that culminate in severe diseases.ConclusionBased on clinical and experimental evidences we propose that platelets modulate the function of hypothalamo-hypophyseal-ovarian system. Specifically, hypothalamic GnRH releases FSH from the anterior pituitary, which induces and stimulates follicular and oocyte maturation and steroid hormone secretion in the ovary. At the same time follicular cells enhance PAF production. Through these pathways activated platelets are accumulated in the follicular vessels surrounding the follicle and due to its released soluble molecules (factors, mediators, chemokines, cytokines, neurotransmitters) locally increase oocyte maturation and hormone secretion. Therefore we suggest that platelets are not only a small participant but may be the conductor or active mediator of this complex regulatory system which has several unrevealed mechanisms. In other words platelets are corpuscular messengers, or are more than a member of the family providing hemostasis.

Aim: Anorexia nervosa is a complex psychiatric disorder posing a rapidly increasing burden on modern societies. Our purpose was to clarify perceptualmotivational aspects of gustatory disturbances in the disease. Methods:A taste reactivity test, with the use of all five primary qualities in two concentrations, was performed in restrictive-type anorexic patients, and their hedonic evaluations were compared to those of agematched healthy control subjects.Results: The patients gave significantly lower pleasantness scores for pleasant taste stimuli compared with controls. The differences were the greatest for the lower concentration sucrose, umami and sodium chloride. Ratings given for the aversive taste stimuli were similar in both experimental groups. Conclusion:Our findings contribute to a better understanding of complex symptoms of anorexia nervosa, and may also help to develop more effective cognitive-behavioral therapies.