1
|
Enna SJ, Williams M. Defining the role of pharmacology in the emerging world of translational research. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2009; 57:1-30. [PMID: 20230758 DOI: 10.1016/s1054-3589(08)57001-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Pharmacology is focused on studying the effects of endogenous agents and xenobiotics on tissue and organ function. Analysis of the concentration/response relationship is the foundation for these assessments as it provides quantifiable information on compound efficacy, potency, and, ultimately, side-effect liability and therapeutic index. Historically, pharmacology has been viewed as a unifying, hierarchically integrated, and technologically agnostic discipline. Besides being important in the development of new medications, pharmacological research has led to a better understanding of disease pathogenesis and progression. By defining the effects of compounds in vitro and in vivo, pharmacology has provided the means to validate, optimize, and advance new chemical entities (NCEs) to human testing. With the advent of molecular biology-based assay systems and a technology-driven (high-throughput screening, combinatorial chemistry, SNP mapping, systems biology) reductionistic focus, the integrated, hypothesis-driven pharmacological approach to drug discovery has been de-emphasized in recent years. This shift in research emphasis is now viewed by many as a major factor in the decline of new drug approvals and has led to various initiatives, the most notable being the Critical Path and Phase 0 clinical trial initiatives launched by the US Food and Drug Administration (FDA). These programs underscore the growing need for individuals trained in integrative pharmacology and having a background in molecular pharmacology to drive the drug discovery process and to fostering the translational research that is now considered vital for more rapidly identifying novel, more effective, and safer medications.
Collapse
Affiliation(s)
- S J Enna
- Department of Molecular and Integrative Physiology, Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, Kansas, USA
| | | |
Collapse
|
2
|
Halliwell RF. A short history of the rise of the molecular pharmacology of ionotropic drug receptors. Trends Pharmacol Sci 2007; 28:214-9. [PMID: 17416425 DOI: 10.1016/j.tips.2007.03.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 02/12/2007] [Accepted: 03/23/2007] [Indexed: 11/17/2022]
Abstract
Remarkably, perhaps, for many pharmacologists today, just over 25 years ago, receptors were still considered hypothetical entities. The isolation and identification of Langley's receptive substance (Ehrlich's side-chains) required efforts from diverse groups; serendipity also facilitated its purification and subsequent biochemical and molecular characterization. In this review, I consider some of the key individuals and breakthrough technical developments from the late 1950s to the early 1990s that lead to the cloning of the first receptors. I focus on the nicotinic acetylcholine receptor to illustrate the complexities in this field and because it was the first receptor to be cloned. This brief history will also touch upon the implications of the rise of molecular pharmacology for the development of new drugs.
Collapse
Affiliation(s)
- Robert F Halliwell
- T.J. Long School of Pharmacy and Health Sciences, University of the Pacific, Stockton, CA 95211, USA.
| |
Collapse
|
3
|
Cao CJ, Young MM, Wong JB, Mahran LG, Eldefrawi ME. Putative cocaine receptor in striatum is a glycoprotein with active thiol function. MEMBRANE BIOCHEMISTRY 1989; 8:207-20. [PMID: 2562128 DOI: 10.3109/09687688909026815] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Dopamine transporters of bovine and rat striata were identified by their specific [3H]cocaine binding and cocaine-sensitive [3H]dopamine [( 3H]DA) uptake. Both binding and uptake functions of bovine striatal transporters were potentiated by lectins. Concanavalin A (Con A) increased the velocity but did not change the affinity of the transporter for DA; however, it increased its affinity for cocaine without changing the number of binding sites. This suggests that the DA transporter is a glycoprotein and that Con A action on it produces conformational changes. Inorganic and organic mercury reagents inhibited both [3H]DA uptake and [3H]cocaine binding, though they were all more potent inhibitors of the former. n-Ethylmaleimide inhibited [3H]DA uptake totally but [3H]cocaine binding only partially. Also, n-pyrene maleimide had differential effects on uptake and binding, inhibiting uptake and potentiating binding. [3H]DA uptake was not affected by mercaptoethanol up to 100 mM, whereas [3H]cocaine binding was inhibited by concentrations above 10 mM. On the other hand, both uptake and binding were fairly sensitive to dimercaprol (less than 1 mM). The effects of all these sulfhydryl reagents suggest that the DA transporter has one or more thiol group(s) important for both binding and uptake activities. The Ellman reagent and dithiopyridine were effective inhibitors of uptake and binding only at fairly high concentration (greater than 10 mM). Loss of activity after treatment with the dithio reagents may be a result of reduction of a disulfide bond, which may affect the transporter conformation.
Collapse
Affiliation(s)
- C J Cao
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore 21201
| | | | | | | | | |
Collapse
|
4
|
Abstract
High-affinity (Kd approximately equal to 10 nM) binding sites for nicotine and acetylcholine (ACh) have recently been identified in vertebrate brain. It has been suggested that these sites are desensitized ganglionic (C6) nicotinic acetylcholine receptors (nAChRs). We have tested the pheochromocytoma cell line PC12, which is known to contain well-expressed C6 nAChRs, to determine if these nAChRs are associated with high-affinity [3H]ACh-binding sites. We found that the high-affinity nicotinic [3H]ACh-binding site is absent in PC12 cells. We also found that the concentration of nicotine or ACh necessary to desensitize carbamylcholine-stimulated Na+ flux was at least two orders of magnitude greater than the concentrations used in binding experiments. We conclude that high-affinity nicotinic binding sites are not equivalent to C6 ganglionic receptors.
Collapse
|
5
|
Eldefrawi ME, Eldefrawi AT. Coupling between the nicotinic acetylcholine receptor site and the ionic channel site. Ann N Y Acad Sci 1980; 358:239-52. [PMID: 6259991 DOI: 10.1111/j.1749-6632.1980.tb15398.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
6
|
Lukas R, Bennett E. Chemical modification and reactivity of sulfhydryls and disulfides of rat brain nicotinic-like acetylcholine receptors. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)70668-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
7
|
Wei JW, Sulakhe PV. Properties of the muscarinic cholinergic receptors in rat atrium. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1979; 309:259-69. [PMID: 43478 DOI: 10.1007/bf00504759] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
8
|
Eldefrawi ME, Eldefrawi AT, Mansour NA, Daly JW, Witkop B, Albuquerque EX. Acetylcholine receptor and ionic channel of Torpedo electroplax: binding of perhydrohistrionicotoxin to membrane and solubilized preparations. Biochemistry 1978; 17:5474-84. [PMID: 728410 DOI: 10.1021/bi00618a023] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The electric organ of the ray, Torpedo ocellata, can serve as a source for both the acetylcholine (ACh) receptor and its ionic channel. The two entities were identified by their specific binding of [3H]ACh and [3H]perhydrohistrionicotoxin ([3H]H12-HTX), respectively. Binding of [3H]H12-HTX was inhibited by certain drugs and toxins, e.g., histrionicotoxin (HTX), amantadine, and tetraethylammonium (TEA) ions at concentrations that did not inhibit [3H]ACh binding. However, the specific carbamoylcholine-induced 22Na efflux from microsacs from the electric organ membranes was blocked by inhibitors of either the receptor or its ionic channel. The ionic channel had the properties of a protein as judged by heat sensitivity and the inhibition of [3H]H12-HTX binding, after incubation of the electric organ membranes with protein reagents such as p-chloromercuribenzenesulfonic acid (PCMBS) or N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ). The "binding" of [3H]H12-HTX at 4 X 10(-8) M to lipids in the microsacs was 12% of the total binding to intact microsacs and was nonsaturable and insensitive to heat or specific drugs. After solubilization with cholate, the [3H]H12-HTX binding subunits retained the same affinities for toxins and drugs. The Kd for [3H]H12-HTX was 3 X 10(-7) M. The majority of the ionic channel could be separated from the ACh receptors in the cholate extract by incubation with ACh-receptor affinity gel and ACh-receptor antibodies. The ACh receptor purified by this affinity gel contained only a few active ionic channel units as judged by low levels of high affinity binding of [3H]H12-HTX. On the other hand, after solubilization with Triton X-100, all the ionic channel molecules were either separated or denatured so that the purified ACh receptor did not exhibit high affinity binding for [3H]H12-HTX.
Collapse
|
9
|
Frank J, Kriwaczek VM, Marchand C, Schwyzer R. epsilon-Aminocaproylcholine: chemical synthesis, biological properties, and interactions with receptor molecules. Helv Chim Acta 1977; 60:2551-8. [PMID: 599040 DOI: 10.1002/hlca.19770600808] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
10
|
Bregestovski PD, Iljin VI, Jurchenko OP, Veprintsev BN, Vulfius CA. Acetylcholine receptor conformational transition on excitation masks disulphide bonds against reduction. Nature 1977; 270:71-3. [PMID: 927521 DOI: 10.1038/270071a0] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
11
|
OZAKI HIRONOBU. MOLECULAR PROPERTIES AND DIFFERENTIATION OF ACETYLCHOLINESTERASE IN SEA URCHIN EMBRYOS*. Dev Growth Differ 1976. [DOI: 10.1111/j.1440-169x.1976.00245.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
12
|
Sanders DB, Schleifer LS, Eldefrawi ME, Norcross NL, Cobb EE. An immunologically induced defect of neuromuscular transmission in rats and rabbits. Ann N Y Acad Sci 1976; 274:319-36. [PMID: 183587 DOI: 10.1111/j.1749-6632.1976.tb47695.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
13
|
|
14
|
Hansma HG, Kung C. Studies of the cell surface of Paramecium. Ciliary membrane proteins and immobilization antigens. Biochem J 1975; 152:523-8. [PMID: 819001 PMCID: PMC1172505 DOI: 10.1042/bj1520523] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We have developed a procedure to isolate the ciliary membranes of Paramecium and have analysed the membrane proteins by electrophoresis on polyacrylamide gels containing either Triton X-100 or sodium dodecyl sulphate. The electrophoretic pattern on gels containing sodium dodecyl sulphate showed 12-15 minor bands of mol.wt. 25 000-150 000 and on major band of mol.wt. 200 000-300 000 that contained approximately three-quarters of the total membrane protein. 2. We present evidence that the major membrane protein is related to, but not identical with, the immobilization antigen (i-antigen), which is a large (250 000 mol.w.), soluble, surface protein of Paramecium. The similarity of the i-antigen and the major membrane protein was shown by immunodiffusion and by the electrophoretic mobilities in sodium dodecyl sulphate of these two proteins from Paramecium of serotypes A and B. The non-identity of these two proteins was shown by their different electrophoretic mobilities on Triton X-100 containing gels and their different solubilities. 3. We propose that the major membrane protein and the i-antigen have a precursor-product relationship.
Collapse
|
15
|
Eldefrawi ME, Eldefrawi AT, Wilson DB. Tryptophan and cystein residues of the acetylcholine receptors of Torpedo species. Relationship to binding of cholinergic ligands. Biochemistry 1975; 14:4304-10. [PMID: 1182102 DOI: 10.1021/bi00690a026] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Several methods were used to analyze for tryptophan in the acetylcholine (ACh) receptors purified from the electric organs of the electric rays, Torpedo californica and Torpedo marmorata. The best value of tryptophan was 2.4 mol %. When excited at 290 nm, both receptors fluoresced with a maximum at 336, but there was no change in the fluorescence emission spectra upon binding of carbamylcholine, d-tubocurarine, ACh, or decamethonium. The free SH content of the Torpedo receptors varied in different preparations, and was highest in that purified from fresh T. californica using deaerated solutions and dialysis under nitrogen, and lowest in that prepared from the aged lyophilized membranes of T. marmorata. The maximum free SH content was 20 nmol/mg of protein or 0.22 mol %, equal to at most 18% of the total cysteic acid residues. Reaction of either 33% or of all the SH residues with p-chloromercuribenzoate reduced maximum ACh binding to the pure receptor prepared from fresh T. californica by only 23%.
Collapse
|
16
|
Csillik B. Synaptochemistry of acetylcholine metabolism in a cholinergic neuron. INTERNATIONAL REVIEW OF NEUROBIOLOGY 1975; 18:69-140. [PMID: 173665 DOI: 10.1016/s0074-7742(08)60034-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
17
|
Kato G, Tattrie B. Solubilization of the acetylcholine receptor protein from Loligo opalescens without detergents. FEBS Lett 1974; 48:26-31. [PMID: 4430370 DOI: 10.1016/0014-5793(74)81054-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
18
|
Abstract
The idea that certain drugs and neurotransmitters produce their effects by combining with specific receptors was first clearly expressed by Langley (1905) on the basis of the selective and localized effect of nicotine on striated muscle fibres. In 1914, Langley published a paper in which the antagonism between ‘curari’ and nicotine was analysed and measured as the ratio by which the nicotine concentration had to be increased in order to produce a standard response in the presence of tubocurarine. It was clear that Langley had in mind the idea of competition between nicotine and curare for the receptor sites and it was surprising that he did not formulatethe theory quantitatively, particularly since Hill, working in Langley's laboratory in 1909, published a mathematical analysis of the action of nicotine on frog muscle giving kinetic and equilibrium equations based on the law of mass action, which could easily have been extended to give an account of competitive antagonism. Barger & Dale (1910) did not favour the idea of specific receptors for sympathomimetic amines.
Collapse
|
19
|
Franklin RM. Structure and synthesis of bacteriophage PM2, with particular emphasis on the viral lipid bilayer. Curr Top Microbiol Immunol 1974:107-59. [PMID: 4614956 DOI: 10.1007/978-3-642-66044-3_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
20
|
|
21
|
Patrick J, Lindstrom J, Culp B, McMillan J. Studies on purified eel acetylcholine receptor and anti-acetylcholine receptor antibody. Proc Natl Acad Sci U S A 1973; 70:3334-8. [PMID: 4128544 PMCID: PMC427231 DOI: 10.1073/pnas.70.12.3334] [Citation(s) in RCA: 119] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Rabbit antiserum against purified Electrophorus electricus acetylcholine receptor is studied using an immunoprecipitin assay to measure either antibody titer or concentration of toxin-binding sites in solubilized receptor preparations. This antiserum, unlike control serum, blocks the electrophysiological response of the electroplax to carbamylcholine. Toxin (alpha-neurotoxin, Naja naja) and several cholinergic ligands produce partial inhibition of the reaction of antiserum with purified acetylcholine receptor. Evidence is presented that some of the toxin-binding sites on receptor, purified by affinity chromatography on toxin-agarose conjugates, are occluded by toxin. In addition, evidence is presented that antireceptor antiserum will cause precipitation of more toxin-binding sites present in an initial extract than in purified receptor preparations.
Collapse
|
22
|
|
23
|
Powell JT, Bon S, Rieger F, Massoulié J. Electrophorus acetylcholinesterase: a glycoprotein; molecular weight of its subunits. FEBS Lett 1973; 36:17-22. [PMID: 4747597 DOI: 10.1016/0014-5793(73)80327-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
24
|
McNamee MG, McConnell HM. Transmembrane potentials and phospholipid flip-flop in excitable membrane vesicles. Biochemistry 1973; 12:2951-8. [PMID: 4354249 DOI: 10.1021/bi00740a001] [Citation(s) in RCA: 118] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
25
|
Olsen RW, Meunier JC, Changeux JP. Progress in the purification of the cholinergic receptor protein from Electrophorus electricus by affinity chromatography. FEBS Lett 1972; 28:96-100. [PMID: 4646881 DOI: 10.1016/0014-5793(72)80686-0] [Citation(s) in RCA: 166] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
26
|
Vogel Z, Sytkowski AJ, Nirenberg MW. Acetylcholine receptors of muscle grown in vitro. Proc Natl Acad Sci U S A 1972; 69:3180-4. [PMID: 4508312 PMCID: PMC389730 DOI: 10.1073/pnas.69.11.3180] [Citation(s) in RCA: 218] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
[(125)I]Monoiodo- and [(125)I]diiodo-alpha-bungarotoxin were synthesized and shown to bind specifically to the acetylcholine receptor of cultured embryonic chick- and rat-muscle cells. The pharmacologic properties of the receptor of cultured embryonic chick muscle resembled those of the nicotinic acetylcholine receptor of adult vertebrate muscle. Autoradiography of muscle cells labeled with toxin showed that acetylcholine receptors were distributed over the entire cell surface. In addition, discrete areas with a high receptor concentration were found.
Collapse
|