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Objectives/Hypothesis: Absorbable hemostatic agents are used routinely following sinus surgery. Recent studies suggest that current biomaterials, such as FloSeal Matrix Hemostatic Sealant (Fusion Medical Technologies, Mountain View, CA) may interfere with mucosal regeneration. This study was designed to evaluate the effects of Microporous Polysaccharide Hemospheres (MPH, Medafor, Inc., Minneapolis, MN), a novel rapidly-absorbing hemostatic powder, on healing and intact sinus mucosa. Study Design: Prospective, controlled study using the rabbit model. Methods: Both maxillary sinuses of 14 New Zealand white rabbits were surgically opened. The mucosa of 10 rabbits were stripped bilaterally, and the left sinus of each was then treated with either MPH or FloSeal. The mucosa of four additional rabbits were incised but otherwise remained undisturbed. Again, the left sinus of each of the four additional rabbits was treated with either MPH or FloSeal. The right sinus served as an untreated control (stripped or intact) in both arms of the study. Animals were recovered and euthanized 2 weeks later. Specimens were examined by a blinded pathologist using light microscopy. Results: Untreated regenerated mucosa showed expected areas of sparse cilia, mild serous gland reduction, and fibrosis. MPH-treated sinuses showed no significant changes compared to respective controls, and no MPH substance was identified. In contrast, regenerating mucosa treated with FloSeal showed extensive loss of cilia, inflammation, and fibrosis. Residual FloSeal particles were present within the sinus cavity and grossly incorporated within healing mucosa. Unexpectedly, intact mucosa exposed to FloSeal showed similar findings. Conclusions: Absorbable hemostatic materials have starkly different effects on mucosal healing. Unlike other agents, MPH is rapidly cleared and has no negative effects on healing or intact sinus mucosa.

RET fused gene (RFG)/ELE1alpha/androgen receptor-associated protein 70(ARA70) was first found to be involved in the activation of the RET proto-oncogene in thyroid neoplasm and has recently been shown to be a ligand-dependent transcriptional coregulator for androgen receptor (AR). The functionality of RFG/ELE1alpha/ARA70 remains controversial, and little is known about factors regulating its expression in the prostate. Of significant interest is whether this molecule is involved in prostate carcinogenesis. Using reverse transcriptase-polymerase chain reaction semiquantitation, we compared RFG/ELE1alpha/ARA70 mRNA levels in four prostate cancer cell lines (LNCaP, TSU-Pr1, DU-145, and PC-3) with those found in primary cultures of normal prostatic epithelial cells (PrECs). In addition, we examined the effects of androgen and antiandrogen, estrogen and antiestrogen, and a demethylating agent on RFG/ELE1alpha/ARA70 mRNA expression levels in AR- and AR+ PC-3 cells. Reduced levels of RFG/ELE1alpha/ARA70 message were observed in all four prostate cancer cell lines when compared with normal PrECs in primary cultures. RFG/ELE1alpha/ARA70 mRNA levels in PC-3 cells, which express both estrogen receptor subtypes, were upregulated by 17beta-estradiol and inhibited by the antiestrogen ICI-182780. In PC-3(AR+) cells, which were genetically engineered to express AR, exposure to androgen upregulated RFG/ELE1alpha/ARA70 mRNA expression, whereas treatment with 4-hydroxyflutamide lowered expression of this transcript. Furthermore, treatment of DU-145 cells, which did not express RFG/ELE1alpha/ARA70 transcripts, with a demethylating agent reactivated transcription of this gene. Polymerase chain reaction analyses of monochromosomal human-rodent hybrid panels localized a putative RFG/ELE1alpha/ARA70 isoform on human chromosome 5q31.1-31.2. In summary, we identified sex hormones and DNA hypermethylation as regulators of RFG/ELE1alpha/ARA70 expression in prostate cancer cells. In addition, we found reduced levels of RFG/ELE1alpha/ARA70 expression in prostate cancer cell lines when compared with expression levels in normal PrECs in culture. These findings suggest that RFG/ELE1alpha/ARA70 may be involved prostate carcinogenesis and that it may serve as a key mediator of estrogen-androgen synergism.

Potential reasons for discordance between the Gleason score in biopsies and surgical specimens are: 1) pathological interpretation bias, and 2) sampling effects. The importance of sampling effects in grading errors was examined in a series where the number of biopsy cores obtained was high. Biopsies were obtained using a technique whereby 18 directed cores were systematically obtained and mapped out within the gland. Gleason scores from biopsies and matched prostatectomy specimens were compared among 28 consecutive patients with localized prostate cancer. A pooled database from 10 series (n = 2,687) served as a baseline for comparison in the accuracy of Gleason score grading. With the present biopsy technique, an exact Gleason score match was achieved in 57% of cases, compared with the pooled database (PD) mean of 42% (P = 0.055), and was within 1 point in 93% of cases compared with 78% (PD) (P = 0.029). Upgrading of biopsies was seen in 35% of cases, compared with 43% (PD) (P = 0.19). With respect to Gleason score 7, an exact match was present in 78% of cases, compared with 63% (PD) (P = 0.17), and upgrading was 0%, compared with 20% (PD) (P = 0.07). The data suggest a significant reduction in grade errors by minimizing sampling effects, one that it is of the same order of magnitude as the reduction achieved from consensus pathologic evaluation. In our study, seven patients (25%) would have had their cancers missed altogether with sextant biopsies. Sampling effects may contribute significantly to grading errors in prostate needle biopsies, although a larger study is needed to confirm this. A methodology which adopts a higher number of cores combined with a consensus pathologic evaluation could potentially reduce grading errors substantially. The optimal number of cores remains to be determined in a larger study. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 326–330 (2000). © 2000 Wiley-Liss, Inc.

Germline mutations of BRCA1 and BRCA2 predispose to hereditary breast, ovarian, and possibly prostate cancer, yet structural mutations in these genes are infrequent in sporadic cancer cases. To better define the involvement of these genes in sporadic cancers, we characterized expression levels of BRCA1 and BRCA2 transcripts in cancer cell lines derived from neoplasms of the ovary, prostate, and breast and compared them with those expressed in primary cultures of normal epithelial cells established from these organs. We observed upregulation of BRCA1 and/or BRCA2 expression in six of seven ovarian cancer cell lines (OVCA420, OVCA429, OVCA432, ALST, DOV13, and SKOV3) when compared with levels found in normal ovary surface epithelial cells. Furthermore, five cancerous or immortalized prostatic epithelial cell lines (BPH-1, TSU-Pr1, LNCaP, PC-3, and DU145) also expressed higher levels of BRCA1 and/or BRCA2 mRNA than did primary cultures of normal prostatic epithelial cells. In contrast, only the estrogen receptor-positive MCF-7 cell line overexpressed these messages, whereas the estrogen receptor-negative breast cancer cell lines Hs578T, MDA-MB-231, and MDA-MB-468 showed no change in expression levels when compared with normal breast epithelial cells. In addition, expanding on our recent identification of a novel BRCA2 transcript variant carrying an in-frame exon 12 deletion (BRCA2 delta 12), we report increased expression of this variant in several ovarian, prostate, and mammary cancer cell lines (OVCA420, OVCA433, ALST, DOV13, SKOV3, TSU-Pr1, DU145, and MDA-MB-468). Most notably, high levels of BRCA2 delta 12 mRNA were detected in an estrogen receptor-positive breast cancer cell line, MCF-7, and in an androgen-independent prostate cancer cell line, DU-145. Interestingly, the wild-type BRCA2 transcript was barely detectable in DU145, which could be used as a model system for future investigations on BRCA2 delta 12 function. Taken together, our data suggest disruption of BRCA1 and/or BRCA2 gene expression in certain epithelial cancer cell lines of the ovary, prostate, and breast. Because wild-type BRCA1 and BRCA2 gene products increase during cell-cycle progression and are believed to exert growth-inhibitory action, enhanced expression of these genes in cancer cells may represent a negative feedback mechanism for curbing proliferation in fast-growing cells. At present, the functionality of BRCA2 delta 12 remains elusive.

A case of collecting-duct carcinoma associated with abnormal urine cytology is described. The finding of an abnormal cytologic examination, yet not typical of transitional-cell carcinoma (TCC), suggests that a close relationship between the cytology and histology of this uncommon malignancy may be demonstrated.

In order to facilitate identification of possible metabolites arising from in vitro action of catechol-O-methyltransferase upon 7,8-dihydroxy- and 8,9-dihydroxy-4-n-propyl-1,2,3,4,4a,5,6,10b-octahydrobenzo[f]quinolines (11, 12), all four possible monomethyl ether derivatives have been synthesized. Incubation of 11 and 12 with the enzyme revealed that the 8,9-dihydroxy positional isomer 12 (which contains the dopamine moiety held in the beta conformation) but not the 7,8-dihydroxy isomer 11 (which holds the dopamine moiety in the alpha conformation) was a substrate for the enzyme. The sole detectable product of 12 was 8-hydroxy-9-methoxy derivative 15 in which the "meta" hydroxy group of the dopamine moiety is etherified.

The subject compounds were prepared as a part of a continuing structure-activity study of the contrasting actions (agonism-antagonism) of (+)- and (-)-11-hydroxy-10-methylaporphine at serotonin (5-HT1A) receptors. None of the targeted nonoxygenated aporphine derivatives demonstrated significant activity in assays for any effects at serotonin 5-HT1A receptors. It is concluded that, in the aporphine series, serotonergic agonist or antagonism requires an alkyl group ortho to a phenolic OH group in the A ring.

CK-1649C is a new quaternary ammonium class III antiarrhythmic agent undergoing clinical trials. The side effect profile of a class III antiarrhythmic agent is generally unknown. This study compared CK-1649C with quinidine and lidocaine (class I), acecainide (class I/III), and clofilium (class III), in several models of smooth muscle, platelet, skeletal muscle, and central and peripheral nervous system function, to evaluate the potential side effects of this new drug. CK-1649C was devoid of neuropharmacologic activity in the mouse and rat. CK.-1649C did not promote gastrointestinal hypermotility in the mouse fed a charcoal meal and was also inactive in the rat carrageenan-induced paw edema test. Ten to 30 times the antiarrhythmic dose of concentration of CK-1649C was devoid of activity on transmural nerve stimulation and did not exhibit α1-muscarinic, nicotinic, or β-adrenoceptor blocking activity in canine vascular and guinea pig nonvascular smooth muscle. CK-1649C was devoid of effects on human platelets, nonvascular smooth muscle of guinea pig vas deferens and uteri, and rabbit bronchi, responses of the anesthetized dog to intravenous acetylcholine (ACh), isoproterenol, and nicotine; cervical sympathetic transmission to the nictitating membrane of dog; and free water clearance in water-loaded dogs. CK-1649C (30mg/kg, i.v.) was devoid of all but transient inhibitory activity against vagal nerve stimulation in the dog. CK-1649C should not have significant hemodynamic, neural, or smooth muscle side effects at proposed therapeutic doses of 1–3 mg/kg in man.

Sematilide is a new, non-quaternary class III antiarrhythmic agent currently undergoing clinical trials. We showed that a quaternary ammonium class III antiarrhythmic agent exhibits few extracardiac effects (Greenberg et al., Drug Dev. Res. 25.107–123, 1992). However, the extracardiac effects of a non-quaternary, pure class III antiarrhythmic agent are unknown. Sematilide, a pure class III antiarrhythmic agent, is effective in a canine model of arrhythmia at 0.3–1.0 mg/kg, intravenously (i.v.). We compared the nervous system and extracardiac effects of sematilide to acecainide (a class I/III) and several class I antiarrhythmic agents to evaluate the potential side effects of this new drug. Sematilide was devoid of neuropharmacologic activity in the mouse and rat, devoid of gastrointestinal activity in the mouse fed a charcoal meal, and without effect in the rat carrageenan-induced paw edema test. Ten to 30 times the average antiarrhythmic dose or plasma levels of sematilide were devoid of α1, muscarinic, nicotinic, and β-adrenoceptor blocking activities in a variety of preparations. Moreover, sematilide was devoid of depressant activity on (1) cholinergic, nicotinic, and sympathetic neurotransmission; (2) vascular and non-vascular smooth muscle reactivity and contractility; (3) aggregation of human platelets; (4) responses of the anesthetized dog to i.v. acetylcholine, isoproterenol, and nicotine; and (5) displacement of quinuclidinyl benzilate (QNB) binding to dog atrial membranes. Sematilide (10–30 mg/kg, i.v.) inhibited vagal nerve stimulation in the dog and slightly enhanced free water clearance in water-loaded dogs. The data show that effective antiarrhythmic doses and concentrations of sematilide are devoid of significant, injurious neural, hemodynamic, or smooth muscle side effects. © 1992 Wiley-Liss, Inc.

The two enantiomers of the title compound have been prepared by different synthetic routes. Both bind strongly to 5-HT1A receptors from rat forebrain membrane tissue. However, in a guinea pig ileum preparation, the (R)-enantiomer exhibits properties consistent with its being an agonist, whereas the (S)-enantiomer shows no agonist effect, but it blocks the actions of the (R)-enantiomer and of 8-hydroxy-2-di-n-propylaminotetralin (8-OH-DPAT), a 5-HT1A agonist. These data are presented as a rare example of enantiomers which demonstrate opposite pharmacological effects at the same receptor.

In vitro experiments using isolated atria with and without superfusion can be used to quantify the dopamine-2 (DA-2) receptor stimulating activity of compounds. This receptor mechanism decreases the amount of norepinephrine released from sympathetic nerve terminals by neuronal impulses. DA-2 receptor agonists (stimulants) are very active and induce several physiological changes, such as bradycardia, hypotension, lower intraocular pressure, etc. In this unit, tissue preparation and dopamine receptor assays are described for isolated cat atria with field stimulation or with superfusion, and isolated guinea pig atria with field stimulation.

RDS-127 (2-di-n-propylamino-4,7-dimethoxyindane) is a novel dopamine (DA) receptor agonist with potent central actions. RDS-127, apomorphine (APO), and bromocriptine (BRM) were compared for their ability to inhibit locomotor activity in rats following oral administration. APO, BRM, and RDS-127 produced time- and dose-dependent decreases in locomotor activity. While APO and BRM were equipotent in inhibiting locomotor activity, RDS-127 was 13.5 times more potent than either APO or BRM. A single oral dose of 32.0 μmol/kg of RDS-127 decreased locomotor activity greater than 50% for a period of 2 hr. The inhibitory effects of RDS-127 on locomotor activity were blocked by prior administration of sulpiride, suggesting the effects are mediated by DA receptors. While oral administration of APO or RDS-127 generally decreased locomotor activity, similar doses given subcutaneously increased locomotor activity. These data suggest that the route of administration can profoundly affect the biological actions of DA receptor agonists and the accompanying conclusions concerning the selectivity with which they interact with different receptor subtypes. The therapeutic application and design of orally effective DA autoreceptor agonists are discussed.

The cardiovascular effects of two N-di-alkyl substituted analogs of dopamine and dopamine were tested in the dog. Intravenous administration of N, N-diethyldopamine (DEDA) decreased mean arterial pressure, heart rate, and mildly depressed cardiac output. Intravenously administered N, N-dipropyldopamine (DPDA) decreased mean arterial pressure, heart rate, and total peripheral vascular resistance. Both compounds inhibited reflex sympathetic responses produced by a bilateral common carotid occlusion. Femoral artery injections of DEDA or DPDA produced biphasic responses. A transient increase in femoral bed vascular resistance was followed by a decrease in femoral bed vascular resistance sensitive to alpha adrenoceptor antagonism. In contrast to DEDA and DPDA, intravenously administered dopamine increased cardiac output and heart rate while reducing arterial pressure and total peripheral vascular resistance. Femoral artery injections of dopamine resulted in a dose-dependent constrictor response which was antagonized by alpha receptor blockade. These data demonstrate that DEDA and DPDA induce different cardiovascular responses from dopamine.

Secondary and tertiary amino homologs of the title compounds have been prepared, bearing an N-isopropyl group. In peripheral evaluation, certain members of the series exhibited beta-adrenergic agonist effects of lower activity than isoproterenol. N-Methyl-N-isopropyl-5,6-dihydroxytetralin exhibited marked properties consistent with its being an alpha agonist, and it is concluded that introduction of considerable bulk about the nitrogen of a catecholamine does not a priori destroy alpha-agonist effects. The compounds qualitatively paralleled the effects of dopamine in assays based upon direct intrastriatal administration in rats, although they were less potent than dopamine.

N-Alkylated derivatives of 2-amino-4,7-dimethoxyindan were prepared for evaluation of central and peripheral dopaminergic activity using biochemical and behavioral tests in the rat and cardiovascular responses in the cat. 2-(Di-n-propylamino)-4,7-dimethoxyindan (4e) demonstrated equal activity with apomorphine to activate peripheral presynaptic dopamine receptors. Central pre- and postsynaptic dopamine receptors were also activated with 4e. In contrast to the intense long-acting sympathomimetic actions previously reported for the 2-amino-5,8-dimethoxytetralins, these compounds produced weak, transient effects in heart rate and blood pressure. The majority of 2-amino-4,7-dimethoxyindan derivatives tested are weak or inactive pre- and postsynaptic dopamine receptor agonists.

Series of N-alkylated derivatives of 2-amino-4,6-dihydroxyindan 3 and 6-amino-1,3-dihydroxybenzocycloheptene 2 were prepared for pharmacological testing as congeners of 2-amino-5,7-dihydroxytetralin, which elicits dopaminergic effects in a variety of assays. All of the subject compounds demonstrated a lower order of dopamine-like activity than the tetralin derivatives. Some of the subject compounds showed weak interactions with alpha 1- and beta 1-adrenoceptors, but the major determinant of activity seemed to be the nature of the N-alkyl substituent rather than ring size.

The N-n-propyl homologues of the title compounds were prepared for further assessment of the ability of the "p-dimethoxy" moiety to confer dopaminergic agonism upon a variety of ring systems. Both the angularly and the linearly annulated trans-benzoquinoline ring derivatives displayed prominent DA2 dopaminergic effects on the peripheral sympathetic nerve terminal and displayed postjunctional dopamine receptor agonist properties in the striatum. It is speculated that the angular octahydrobenzo[f]quinoline derivative (but not the linear octahydrobenzo[g]quinoline derivative) may owe its dopamine-like effects to metabolic activation phenomena. In contrast, the cis-fused isomer of the angularly annulated benzoquinoline was inactive, as was the simple benzene derivative N,N-di-n-propyl-beta-(2,6-dimethoxyphenyl)ethylamine.

The title compounds were designed to provide semirigid congeners of m-tyramine in which the ring position ortho to the phenolic OH is blocked to metabolic hydroxylation. A sequence leading to a key synthetic intermediate, 5-methoxy-6-methyl-2-tetralone, has been developed. In animal test models for dopamine-like effects, the title compounds demonstrated qualitative and quantitative differences from the isomeric 5-methyl-6-hydroxy-2-aminotetralins and from 5,6-dihydroxy-2-aminotetralins. Two of the compounds were potent in a cat cardioaccelerator nerve assay, which involves dopamine receptors.

Replacement of the catechol 3,4-dihydroxylation pattern of certain adrenergic beta-phenethylamines by a resorcinol 3,5-dihydroxylation pattern has led to a greater selectivity of adrenergic agonist effects in certain molecules. This strategy has been applied to a series of dopaminergic agents derived from 2-aminotetralin, leading to a 5,7-dihydroxylation pattern. Traditional literature approaches to formation of a tetralin ring with this oxygenation pattern failed. A method was used which involved cyclization of 3,5-dimethoxybenzylsuccinic acid derivatives with pyridinium poly(HF) and subsequent modification of the tetralin ring. The resorcinol-derived 2-aminotetralins were less potent and less active dopaminergic agents than their catechol-derived isomers (5,6-dihydroxy and/or 6,7-dihydroxy). Certain of the subject compounds demonstrated alpha- and beta 1-adrenoceptor activating properties.

The title compounds were prepared as congeners of the dopaminergically potent 2-amino-5,6-dihydroxytetralin series ("A-5,6-DTN"). None of the variously nitrogen-substituted benzocycloheptenes demonstrated any dopamine-like effects in a variety of assays. The primary amine had alpha 1-adrenoceptor stimulant effects. This lack of dopaminergic effect parallels the inactivity found in 6-aminobenzocycloheptenes bearing no oxygen substitutents, those bearing a single phenolic group, and those bearing a resorcinol 1,3-diphenolic substitution pattern.

Two series of N-substituted 2-aminoindan systems have been prepared: 4,5-dihydroxy-2-aminoindan (1) has a hydroxylation pattern analogous to the alpha conformer of dopamine, and 5,6-dihydroxy-2-aminoindan (2) has a hydroxylation pattern of the beta conformer of dopamine. All members of both series demonstrated only extremely weak binding to calf caudate homogenate. Certain N-alkylated 4,5-dihydroxyindans were violent emetics in the dog and were potent in blockade of the effect of stimulation of the cardioaccelerator nerve of the cat. In contrast, the 5,6-dihydroxy series displayed low or no activity/potency in these assays. Conformational analysis of the 2-aminoindan system is described and discussed.

The vinyl ethers of choline and of its alpha- and beta-methyl homologues were prepared to determine their cholinergic effects and to determine whether a separation of the dual physiologic activity (nicotinic and muscarinic) reported for the vinyl ether of choline could be achieved by this modification. A literature method of vinyl transetherification of amino alcohols has been studied and modified. The ethyl ethers of choline and of alpha- and beta-methylcholine were prepared for comparison with the vinyl ethers. Two independent, unequivocal syntheses of the ethyl ether of beta-methylcholine have been accomplished. This study showed that the two literature methods for synthesis of this compound are equivocal, and, hence, the biological data reported for this compound in the older literature may not be valid. Certain of the ethers showed marked nicotinic or muscarinic activities.

The title compounds have been synthesized and evaluated for emetic effects in the dog, actions on the cardioaccelerator nerve in the cat, pecking in pigeons, and for behavioral effects following both peripheral and direct intracerebral injection into the nucleus accumbens and caudate-putamen of the rat. Generally, in the series studied, the N,N-diethyl and N,N-di-n-propyl congeners of dopamine displayed notably high degrees of activity. However, the test compounds exerted differing effects on peripheral and central dopamine receptors and in the area postrema. Differentiations of the activities of the different homologues within the brain were also shown.

Series of N-alkylated derivatives of trans-octahydrobenzo[g]quinoline and of cis- and trans-octahydrobenzo[f]quinoline were prepared for pharmacological testing as congeners of 2-amino-5,7-dihydroxytetralin, which elicits dopaminergic effects in a variety of assays. Trans-fused compounds bearing N-ethyl or N-n-propyl displayed high potency/activity in inhibition of effect of stimulation of the cat cardioaccelerator nerve. Certain N-alkyl homologues in the octahydrobenzo[f]quinoline series showed high potency in binding studies in rat caudate homogenate.

A synthetic precursor to a potent dopaminergic agonist, (RS)-4-hydroxy-2-(di-n-propylamino)indan, has been resolved by classical recrystallization procedures, and the absolute configurations of the enantiomers have been established by X-ray crystallographic analysis. The enantiomers were converted by literature procedures into (R)- and (S)-1. (R)-1 was approximately 100 times as potent as (S)-1 in an assay for dopamine agonist effect in the isolated cat atrium.

The ortho hydroxy/methyl, hydroxy/hydroxymethyl, hydroxy/formyl, and hydroxy/carboxy substitution patterns, some of which confer dopaminergic agonist effects upon 2-aminotetralin ring systems, have been incorporated into beta-phenethylamine, 2-aminoindan, and trans-octahydrobenzo[f]quinoline rings. Certain of the 2-aminoindan derivatives displayed pharmacologic properties consistent with their being dopaminergic agonists. The beta-phenethylamine derivative did not show any significant dopamine-like activity. The 7-hydroxy-8-methyloctahydrobenzo[f]quinoline derivative 4a was a moderately potent, short-acting DA2 receptor antagonist. All of the carboxylic acid derivatives were inert. Of the ortho hydroxy/methyl derivatives, only the 5-hydroxy-6-methyl-2-aminotetralin derivative displayed pharmacological properties consistent with its being a dopaminergic prodrug. It is concluded that 5-hydroxy-6-methyl-2-(di-n-propylamino)tetralin (1a) is structurally unique for a dopaminergic drug.

A series of cis- and trans-dihydroxycotahydrobenzo[f]quinoline congeners of dopamine has been prepared, in which the N substitutent is H, ethyl, or n-propyl. The trans isomers include the dopamine moiety held rigidly in an antiperiplanar diposition which is believed to be necessary for certian central and peripheral dopaminergic effects. The cis isomers are flexible molecules; the dopamine moiety lacks conformational integrity and it can exist in a conformation which is believed not to favor dopaminergic activity. The trans series of compounds was shown to possess a high level of central and peripheral dopaminergic effects, whereas the cis series was of low activity or was inert. These data further support previous proposals concerning stereochemical requirements for certain dopaminergic agonist activity.

The physiological and pharmacological roles of pre- and postsynaptic dopamine receptors in modification of neuronal transmission centrally and peripherally will be subjects for intense research during the next decade. As enumerated by Langer, dopamine-sensitive receptors have been described that may inhibit or facilitate release of neurotransmitter substances. It is likely that dopaminergic agents that are highly selective for specific transmitters will be discovered. Likewise, dopaminergic agents that are nonselective (i.e., that modify the function of two or more neurotransmitters) may offer many opportunities for modification of behavior.

cis- and trans-4-n-Propyloctahydrobenzo(f)quinolines 4a,b were prepared for further assessment of dopaminergic effects of non-oxygenated dopamine congeners. The trans isomer 4b exhibited marked dopamine-like effects in the cat cardioaccelerator nerve assay and in a rat rotation model. Compound 4b produced dose-related lowering of blood pressure in the cat. The cis isomer 4a was inactive in these assays. Both compounds were inactive in a dopamine binding assay, but both appeared active in a spiroperidol binding assay. Both compounds are active α1- and α2-adrenoceptor antagonists. Compound 4b provides evidence that α2-adrenoceptors and dopamine receptors are different entities, since this compound is an α2 antagonist and a dopamine receptor agonist at presynaptic sites.

The ergolines are an important class of dopamine receptor agonists1), and the identification of their dopaminergic pharmacophore has been sought as a means of developing “purer” agonists related to these structures2). Ergolines combine a phenethylamine and a pyrroleethylamine moiety, both of which have been proposed as the dopaminergic pharmacophores of the molecules3,4). Support for these postulates is the fact that certain simplified partial ergoline structures5,6) show potent dopamine agonist activities. The simple 3-(2-aminoethyl)pyrrole was also synthesized6) but it was found inert as a dopamine receptor agonist. This inactivity was rationalized on the basis that this primary amino compound is rapidly destroyed in vivo by monoamine oxidases6).