Adrenergic receptor (adrenergic receptor or) are a class of G protein-coupled receptor is a target catecholamines epinephrine, and norepinephrine (noradrenaline) and (adrenaline) in particular. Many cells have a receptor such, catecholamines, usually, binding to the receptor stimulates the sympathetic nervous system. To mobilize energy and redirecting blood flow, sympathetic nervous system is responsible for fight or flight response, including the fundus skeletal muscle, organs from non-essential.
Professor of pharmacology, the United States, published a book of adrenergic neurotransmission in 1948 Raymond Ahlquist, in Georgia, but its meaning will be ignored by the time mainly. However, because he incorporate textbook of pharmacology in medicine, their findings of the drill in 1954, adrenaline / also firmly – it was able to establish an important role in adrenaline cells and mechanisms α of β receptor was. In order not to depend on the effectiveness of the herbal medicine testing existing and traditional targeted condition, revolution its discovery progresses the study of drug therapy in order to enable selection of a particular molecule.
There adrenergic receptors with several subtypes, Group and two α of β.
I have a (GI-coupled receptor) and the α2 (-coupled receptor and Gq) α receptor subtype α1. Phenylephrine is a selective agonist at the α receptor. β receptor subtype, has a β3 β1, and β2. Protein of all three, in order, Associated with adenylate cyclase, which is linked GS (β2 things to GI also couple) to. Cause an increase in intracellular cAMP concentration of second messenger by the agonist binding. After hormone binding, downstream effector of cAMP may be mentioned (PKA) cAMP-dependent protein kinase A in mediating some of the cellular events. Non-selective agonist, is isoprenaline.
[3H] dihydroergocryptine, non-selective adrenergic agonist of α, α-1 selective antagonist, and [3 H] prazosin selective α-2 antagonist [3 H] yohimbine examined the binding sites in rat kidney membrane. To establish a connection between the biological function and binding, the ability to stimulate or inhibit vasoconstriction α adrenergic agent, was quantified in vitro using perfusion kidney preparation was isolated. Approach on radioactive ligand is saturated rapidly, it is certain that. In addition, the order of potency of adrenergic agonists identified by different competitive inhibition study, items with an alpha-adrenergic specificity, binding of each radioligand was suggested. The total number of binding sites of the membrane of rat kidney of these. α-1, substantially equal to the sum of the concentration of binding sites was defined 170 fmol and 57 by / mg, (Bmax is, Bmax (KD, at 12.8 nM [3 H] dihydroergocryptine radioligands α-2 selective , determination of protein by 212 fmol / mg protein); KD, 0,85, and at 20 nM, respectively). However, the results of in vitro because there is a close correlation between the data connection that is specified by the (R = 0.93), vasoconstriction of alpha-receptor-mediated renal arterioles, [3H] prazosin α-1 subtype was. In addition, antagonists nonselective, phentolamine, and [H] prazosin binding studies, powerful WS unlabeled prazosin 5-40 times greater than 400 and functional – 1500 times stronger than α-2 antagonist yohimbine. In these studies, the cell membrane of rat kidney, indicating that it contains binding sites for both α-1, the α-2 adrenergic receptor specificity in a ratio of 1:3 to about 1:00. In spite of the superiority of α-2 receptor α receptor-mediated renal vasoconstriction, it appears in the α-1 type.
Was investigated in fasting anesthetized rats with electrodes implanted into the jejunum and duodenum chronically previously effect phentolamine, prazosin and yohimbine because laparotomy gastrointestinal motility disorders. Caused the primary layer of the total inhibition of the pulse duration of 26.1 (intraperitoneally Nesdonal 40 mg / kg) continuous recording of thiopental anesthetized sky abdominal muscle activity laparotomy / – 1.3 min (/ meaning – SE) in, the period laparotomy after 7.9 minutes – of the unregulated activities, transition propagation frequency of 71.4 / muscle complex and the first (MMC). Normal model MMC, since immediately after or phentolamine (3 mg / kg body weight) and yohimbine (1 mg / kg), respectively, given the length of the inhibited them before laparotomy decreased 49% and 48. In contrast, depression of pulse activity, there is a (50-60 minutes) recovery scheme MMC end after (100 micrograms / kg) cut postlaparotomy initial IM prazosin only to this. These results, inhibition of early intestinal motility induced by laparotomy to suggest that it may contain α-1, the α-2-adrenergic receptors, whereas fracture pattern, MMC is, α- It is due to activation of two receptor
By stimulation of lipid mobilization, catecholamines, plays a central role in the regulation of energy consumed by the lipolysis in adipocytes partially. β-2 adrenergic receptor (BAR-2) is a major receptor of lipolysis in human mast cells. In order to determine obesity and whether to play a role in lipolysis BAR-2 function of the adipocyte subcutaneous, polymorphisms known and 164 codons 16, 27 of this receptor, we fat mass I examined the group of 140 women who have a large difference in. Polymorphism only was common in the study population in codon 16 and 27. Polymorphism Gln27Glu stressed associated with obesity and the relative risk of obesity odds ratio of about 7 to about 10. I had an average fat mass excess of fat in cells of about 50% or more or 20 kg than the control of homo Glu27. However, a significant relationship was observed in the change of the BAR-2 function. Arg16Gly polymorphism is associated with the BAR-2 function that has been modified without changing the BAR-2 expression and the Gly16 carriers show an increase in agonist sensitivity five times. However, it is not associated with obesity significantly. These findings, in women, BAR-2 gene in human, suggesting that genetic mutations in may be very important to lipolysis BAR-2 function in adipose tissue obesity, and energy consumption at least .