实验仪器使用技术

Adrenergic receptors mediate the central and peripheral actions of norepinephrine and epinephrine. Both of these catecholamine messengers play important roles in the regulation of diverse physiological systems and are widely distributed throughout the body. Agonists and an ...

Adrenergic and other G-protein-coupled receptors (GPCRs) are transmembrane molecules with complex secondary and tertiary organization intended to generate the binding pocket within the transmembrane loops (1). Although there are numerous differences in the primary amino a ...

The use of targeted gene disruptions, or knockouts, has become commonplace in many basic research laboratories. In its most common application, this technique enables the researcher to disrupt expression of a specific gene product selectively. This approach has been particularly us ...

Ablation of the mRNA of a targeted protein by the use of antisense DNA and RNA provides degrees of freedom not available in many other strategies to suppress or eliminate gene products (1–3). Numerous examples exist demonstrating the utility of the antisense DNA/RNA strategy for study of signali ...

There are several methods currently available for transfection of DNA into mammalian cells. These include transfection with calcium phosphate (1), diethylaminoethyl (DEAE)-dextran, cationic liposomes, nonliposomal lipid compounds, and electroporation (2). Each of these m ...

A large number of receptors for neurotransmitters and hormones have been identified by pharmacological studies and by molecular cloning. These receptors are divided into homologous families, which consist of a number of even more homologous subtypes. At least nine distinct adrener ...

G protein-coupled receptors (GPCRs) are among the most important targets for pharmacological compounds used in humans. During the last 10 years, more than 1000 genes coding for GPCRs, representing approx 0.1% of the human genome, have been identified, of which at least 200 have been demonstrat ...

As in many other fields of research in biology, the technology of expressing cloned genes in eukaryotic cells has become an increasingly important method for the study of adrenergic receptors (ARs). As developed in Chapter 14, substantial expression of adrenergic receptors can be achieved ...

Primer extension is often used to map the 5′ end of RNA (1). A single-stranded, end-labeled DNA primer is hybridized to RNA first. Using an RNA-dependent DNA polymerase (reverse transcriptase ) and nonradioactive deoxynucleotides, the primer is extended to yield cDNA. The cDNA is then analyzed on a s ...

The functionally diverse group of G-protein-coupled receptors (GPCRs) is a superfamily of membrane receptors. They include receptors for many different signaling molecules, such as peptide and nonpeptide hormones, neurotransmitters, chemokines, prostanoids, and protei ...

The quantification of adrenergic receptor (AR) mRNAs is an important tool in the study of the physiological and pathophysiological regulation of these receptors. Alterations of the levels of these mRNA represent one of the many mechanisms that regulate receptor signaling (1,2). Such al ...

The β-ARs are members of a large family of neurotransmitter receptors, which interact with GTP binding proteins (G-proteins) to modulate second messenger systems (1,2). The β-ARs mediate the physiological effects of the catecholamines epinephrine and norepinephrine; when ligand- ...

Catecholamines exert their physiological effects via binding to cell-surface receptors known as adrenergic receptors (ARs). Based on the pharmacological and physiological effects of various agonists, the adrenergic receptors have been grouped into a single classificatio ...

Single nucleotide polymorphisms exist at a high frequency in the human genome. Estimates of variability suggest that up to 1 in 1000 bp within coding regions of the genome are polymorphic, and the frequency of polymorphism within noncoding regions is even higher at about 1 in 500. Because of redund ...

Dopamine β-hydroxylase is a copper-containing monooxygenase that catalyzes hydroxylation of a phenylethylamine (mainly dopamine in vivo) at the β-C of the side chain to a phenylethanolamine , using molecular oxygen and ascorbic acid as an electron donor. DBH localizes in noradrener ...

Sulfate conjugation is one of the major catabolic processes involved in the inactivation and elimination of a variety of phenolic drugs and other structurally related exogenous agents. Sulfation of pharmacologically active xenobiotics is assumed to promote their biological in ...

The enzymatic activity that catalyzes the reversible hydrolysis of S-adenosyl-L-homocysteine (AdoHcy) to L-homocysteine (Hey) and adenosine (Ado), or, in reverse, the formation of AdoHcy from Hcy and Ado, is known as AdoHcy hydrolase (AHH) (EC 3.3.1.1). Another name for it, obviously, altho ...

Acetylcholinesterase (acetylcholine acetylhydrolase, AChE: EC 3.1.1.7) has been the focus of much attention since it was first suggested that it plays an important role in the rapid destruction of acetylcholine (ACh) in a living organ (Dale, 1914). In the past decade there has been considerab ...

Monoamine oxidase (MAO; EC 1.4:3.4; amine: oxygen oxidoreductase; deaminating; flavine-containing) is an enzyme that oxidizes a variety of monoamine neurotransmitters and neuromodulators, as well as exogenous bioactive monoamines. It was first characterized by (1928) as monoa ...

Histamine N-methyltransferase (HNMT; EC 2.1.1.8) was discovered a little over 25 yr ago. Since that time, HNMT has been the subject of numerous investigations, and although these studies have provided a fundamental understanding of this enzyme, HNMT has not been the subject of a comprehensive r ...