ABSTRACT
Cholecystokinin (CCK) is a polipeptide having many functions in digestive system (regulating motor activity and secretion) and acting as a neuromodulator in central and peripheral nervous systems. Recent research shows that CCK increases insulin and glukagon secretion and activates hypothalamo-pituitary-adrenal axis. It also plays a role in cardiovascular system (CCK has a positive inotropic effect). The aim of this study is to show some recent knowledge in the subject of CCK structure and its function in human body.
Subject(s)
Cholecystokinin/metabolism , Cardiovascular System/metabolism , Digestive System/metabolism , Exocrine Glands/metabolism , Glucagon , Humans , Insulin/metabolism , Insulin Secretion , Nervous System/metabolismABSTRACT
Beta 3-adrenergic receptors (beta 3 ARs) are important structures in the human body but the role they play is not yet very clear. Stimulation of beta 3 AR in adipose tissue causes greater energy expenditure and increases thermogenesis and lipolysis. Mutation of the gene coding beta 3 AR in position 64 with thymidine instead of cytosine leads to the replacement of tryptophan (Trp 64) with arginine (Arg 64) and may be the cause of greater increase in body mass and the decrease in basic metabolism. The data however, is differentiated in populations and cannot be conclusive. The connection has been discovered between the state of the beta 3 ARs and the blood lipid concentration (also differing in populations). In some patients beta 3 AR mutation is correlated with high arterial diastolic pressure, increased incidence of noninsulin-dependent diabetes in younger, increased insulin resistance and diabetes in pregnant. beta 3-AR agonists might be used in treatment of many diseases, which obviously demands further investigations.
Subject(s)
Arginine/metabolism , Mutation , Receptors, Adrenergic, beta-3/metabolism , Thymidine/metabolism , Arginine/genetics , Coronary Disease/metabolism , Cytosine/metabolism , Diabetes Mellitus/metabolism , Energy Metabolism , Humans , Hypertension/metabolism , Lipolysis , Obesity/metabolism , Receptors, Adrenergic, beta-3/genetics , Thermogenesis , Thymidine/genetics , Tryptophan/metabolismABSTRACT
Treatment of tyrotoxicosis with I131 has been performed successfully for more than 50 years. In the beginning some fears occurred concerning possible oncogenity and gonadal lesions in children. Those restrictions are a history now. Radiotherapy can be used as a method of choice in merely intensified thyrotoxicosis especially with diffused thyroid gland enlargement (with the exception of trachea and oesophagus compression cases), after depletion of other efficient treatment methods, with the lack of patient's consent to operation or to thyrostatic treatment. Gravidity, high possibility of pregnancy (4-12 months after the end of treatment) and breast-feeding time are the obvious contraindications. Though hypothyroidism is inevitable side effect after the therapy (replacement therapy is needed) generally proposed doses of I131 should not be limited to avoid low efficacy of the treatment.
Subject(s)
Iodine , Thyrotoxicosis/drug therapy , Contraindications , Female , Humans , Hypothyroidism/chemically induced , Iodine/adverse effects , PregnancyABSTRACT
Galanin, a 29-30 amino-acid neuropeptide is distributed in the central and peripheral nervous systems, the pituitary gland, the gastrointestinal tract and also in the pancreas. The endogenous and exogenous effects of galanin are mediated by three receptor subtypes, which are termed: GALR1, GALR2, and GALR3. Galanin has a significant role in physiological and pathological processes in adults as well as in children. It has an ability to contract smooth muscles in GI (facilitation and inhibition), stimulates reflexes in the CNS, decreases pancreatic amylase secretion, changes transport of electrolytes Na+ and CL-. It takes part in etiopathogenesis of depression, Alzheimer's disease and diarrhoea, exerts tonic inhibition of nociceptive input to the central nervous system and regulates a function of hypothalamic-pituitary system. Galanin decreases insulin and somatostatin secretion, increases glucagon secretion, takes part in prolactin release, stimulates growth hormone-releasing hormone, hypothalamic gonadotropin releasing hormone and corticotropin releasing hormone. It causes increase of somatotropin secretion, luteinizing hormone and foliculotropin release and adrenocorticotropin secretion. The hypothalamic galanin takes part in etiopathogenesis of obesity not only in human reproductive period, but also in adolescence, increasing the appetite and changing fat metabolism. This variety of actions emphasizes the potential importance of this peptide in the regulation of cells function and the need to understand the mechanism by which they act.
ABSTRACT
The quick progress of medical sciences changed somewhat our point of view on the role of Vasoactive Intestinal Peptide in human body. In the following article we have tried to gather all the latest information concerning VIP and its regulatory function. The role in menstrual cycle regulation, in prolactine and in hypothalamo-pituitary-adrenal axis secretion as well as in pancreas' hormones secretion has been described. We also emphasized the role in maintaining the blood pressure. The influence on the digestion, hematopoiesis, cell growth and differentiation was also discussed.
Subject(s)
Vasoactive Intestinal Peptide/physiology , HumansABSTRACT
In the article we discuss the role of serotonin in maintaining homeostasis paying special attention to the endocrinological aspect of the matter. It has been proved that it contributes to hypothalamus and hypophysis secretion regulation and interferes with paracrine activity in digestive and reproductive system. It is also an important constituent of platelets and takes part in aggregation and coagulation. It is known to be an atherogenic factor and to act as a growth stimulator for blood cells. It can be produced in exceed amounts by neoplasm or be released by activated thrombocytes during stress or coagulation. The influence of this hormone on the most of regulation mechanisms seems obvious. Presence of many different receptors as well as their number in all the structures of mammalian body makes it possible to use a range of agonists and antagonists in research concerning psychiatric diseases (e.g. bulimia, anorexia, depression), Alzheimer disease, migraine, hypertension, carcinoid related syndrome, multiple endocrine neoplasms and pre-menstrual syndrome. The promising results enable to use some of the modifiers in their clinical treatment though more research is needed for fully satisfactory effects.
