Adrenergic receptors types

The first adrenergic receptor types to be distinguished from each other were the adrenergic a- and (3-receptors. Initially based on the different cardiovascular effects of epinephrine and norepinephrine, this distinction was borne out more clearly with the synthetic (3-selective agent isoproterenol. Furthermore, subtypes of both a- and (3-receptors can be distinguished by selective agonists (Figure 10.5). 

Organ System Sympathetic Effect d Adrenergic Receptor Type Parasympathetic Effect d Cholinergic Receptor Type ... 

B. Type II and type IV drugs act by blocking beta-adrenergic receptors (type II) or calcium channels (type IV). Their actions are discussed elsewhere (type II, p 131 type IV, p 144). 

Sympathetic blocking agent. A drug that binds to, but does not stimulate, adrenergic receptors of the 3-type. 

Cotecchia S et al (2004) Structural determinants involved in the activation and regulation of G protein-coupled receptors lessons from the ai -adrenergic receptor sub-types. Biol Cell 96 327-333... 

Adrenergic receptor 2 Amino acid variants appear to be associated with receptor function and agonist induced down regulation. Some variants may predispose to some types of asthma and modulate action of (3-2-adrenergic drugs. 

ORGANS OR STRUCTURES SYMPATHETIC (ADRENERGIC) EFFECTS TYPES OF SYMPATHETIC (ADRENERGIC) RECEPTOR PARASYMPATHETIC (CHOUNERGiq EFFECTS... 

Fig. 5.12 (a) Synaptic types along dendritic spines of M/T and GC units uni-, and bi-directional junctions, (b) Transmitter systems at a reciprocal synapse, Mitral-Granule cell junction. [Glu, glutamate (R, receptor) GABA, y-aminobutyric acid (R, receptor) E, intracellular effector and aAR, alpha-adrenergic receptor.]. (From Hayashi et al., 1993.)... 

Stromal tissue is the primary locus of aradrenergic receptors in the prostate. It is estimated that 98% of the a-adrenergic receptors in the prostate are found in prostatic stromal tissue. Of the arreceptors found in the prostate, 70% of them are of the a1A-sub-type.5 This explains why a-adrenergic antagonists are effective for managing symptoms of BPH.6... 

Abbreviations 3ARK1, -adrenergic receptor kinase 1 PLC, phospholipase C GIRK, G-protein-activated inwardly rectifying potassium channel Ca(N, P, Q), N-type, P-type, or Q-type calcium channel. 

Drysdale CM, McGraw DW, Stack CB et al. Complex promoter and coding region beta 2-adrenergic receptor haplo-types alter receptor expression and predict in vivo responsiveness. Proc Natl Acad Sci USA 2000 97 10483-10488. 

Of the many types of adrenergic receptors found throughout the body, which is most likely responsible for the cardiac stimulation that is observed following an intravenous injection of epinephrine ... 

The answer is a. (Hardman, pp 228-229.) Phentolamine is a non-selective a-adrenergic receptor blocker (i.e., it has affinity for both - and ct2-adrenergic receptor sites). It also has a prominent direct relaxant (musculotropic spasmolytic) effect on arterioles, which results in vasodilation and reflex tachycardia. In addition, phentolamine can block the effects of serotonin and will increase hydrochloric acid and pepsin secretion from the stomach. Phentolamine is used for the short-term control of hypertension in patients with pheochromocytoma (i.e., a type of secondary hypertension) because of the high incidence of tachycardia associated with the compound, it is not used chronically for the treatment of essential hypertension... 

The brain contains many other types of second-messenger-independent protein kinases. Examples of other second-messenger-independent protein kinases are listed in Table 23-1. Many of these include enzymes that were identified originally in association with a particular substrate protein but shown later to play a more widespread role in brain signal transduction. The functional role of one of these, [3-adrenergic receptor kinase (PARK), a type of G protein receptor kinase (GRK), is discussed further below. 

The major types of adipose tissue are (1) white adipose tissue, which manufactures, stores, and releases lipid and (2) brown adipose tissue, which dissipates energy via uncoupled mitochondrial respiration. Obesity research includes evaluation of the activity of adrenergic receptors and their effect on adipose tissue with respect to energy storage and expenditure or thermogenesis. 

The prostate gland comprises three types of tissue epithelial or glandular, stromal or smooth muscle, and capsule. Both stromal tissue and capsule are embedded with at -adrenergic receptors. 

Sufficient data were not included in other reports to calculate predictive values. For instance, Drysdale et al. (2000) reported over a twofold difference between responses to bronchodilators in asthmatics who differed in haplotypes of the [1,-adrenergic receptor gene, but predictive values could not be calculated because the number of asthmatics in each response and haplo-type category were not given. Marked differences in mean absorption of digoxin between indi-... 

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