Gene amplification and protein expression of EGFR and HER2 by chromogenic in situ hybridisation and immunohistochemistry in atypical adenomatous hyperplasia and adenocarcinoma of the lung

AIMS

To investigate the importance of gene amplification and EGFR (epidermal growth factor receptor) and HER2 protein expression during the progression of adenocarcinoma of the lung.

METHODS

EGFR and HER2 gene amplification was examined in atypical adenomatous hyperplasia (AAH), bronchioloalveolar carcinoma (BAC), and adenocarcinoma with mixed subtypes (MX) by chromogenic in situ hybridisation (CISH), and protein expression was examined by immunohistochemistry using paraffin wax embedded tissues.

RESULTS

EGFR and HER2 gene amplification was found in four and two of 86 cases, respectively, and was detected only in the invasive components of MX. EGFR and HER2 protein expression was seen in 24 and 18 of 86 cases, respectively. EGFR and HER2 proteins were not expressed in AAH but were expressed in one BAC case each. EGFR and HER2 proteins were expressed in 23 and 17 of 55 adenocarcinomas with MX. EGFR and HER2 protein expression was seen more often in the invasive components than in the BAC components of MX, and increased significantly as lesions progressed from AAH to BAC, early MX, and overt MX. Because EGFR and HER2 protein expression was frequently seen without gene amplification, other mechanisms apart from gene amplification may be associated with protein expression.

CONCLUSIONS

EGFR and HER2 gene amplification may be a late event and EGFR and HER2 protein expression may be associated with the development of adenocarcinoma of the lung.

Paraovarian cyst: MR imaging features

BACKGROUND

Paraovarian cysts are common intrapelvic neoplasms, but the magnetic resonance (MR) findings of paraovarian cyst have never been reported. We investigated the spectrum of MR imaging features of paraovarian cyst.

METHODS

MR images of 18 paraovarian cysts in 16 patients were reviewed retrospectively. MR images were evaluated for the size and location of paraovarian cysts, single or multicystic, signal intensity on T1- and T2-weighted images, and visualization of the normal ovary on the affected side.

RESULTS

The normal ovary of the affected side was recognized in 13 lesions. Four of these 13 cysts were separated from the ipsilateral ovary. In seven cysts, the normal ovary was abutted by cysts but maintained its shape. In two cysts, the beak sign was recognized at the interface between the cyst and the ovary. Most other MR features were nonspecific.

CONCLUSION

Most paraovarian cysts were homogeneous cystic masses near the ipsilateral round ligament and the uterus. Demonstration of a normal ipsilateral ovary close to, but separated from, the adnexal cyst may be an important MR finding for the diagnosis of paraovarian cysts.

Elbow synovial fold syndrome: MR imaging findings

OBJECTIVE

We describe the anatomy and MR imaging appearance of elbow plicae.

MATERIALS AND METHODS

First, five cadavers were evaluated by sectioning and using MR arthrography for evidence of normal or prominent synovial folds to determine the potential origin of elbow plicae. Next, 164 consecutive MR images were evaluated to determine the frequency of the plicae in a clinical population. Last, we retrospectively studied a selected group of eight patients who underwent preoperative MR imaging and in whom enlarged synovial folds were confirmed at surgery.

RESULTS

In the cadavers, the synovial fold appeared to originate from the synovium adjacent to a posterior fat pad. In the clinical population, half the patients showed a synovial fold at the same location; however, most folds were less than or equal to 2 mm in thickness. The eight patients presented clinically with symptoms mimicking an intraarticular body. The synovial fold in symptomatic patients was seen posteriorly just above the olecranon and averaged 3 mm in thickness.

CONCLUSION

A synovial fold extending from the posterior fat pad in the elbow is a frequent finding on MR imaging. In a subgroup of patients, plicae, when thickened, may present clinically as a locking elbow. However, overlap exists between the thicknesses of symptomatic and asymptomatic plicae.

Utilization of "used" vials: cost-effective technique for MR arthrography

Because full vials of commercially available MR arthrographic contrast are expensive, we hypothesized that the small residual contrast in a "used" vial would be adequate for MR arthrography. After sterility testing and quantity analysis of the residual contrast in 28 vials, this method was successfully used in 10 patients. J. Magn. Reson. Imaging 2000;12:953-955.

Does granulocyte colony-stimulating factor exacerbate radiation-induced acute lung injury in rats?

Radiation pneumonitis (RP) frequently occurs as a complication of thoracic irradiation. However, the mechanism of RP is not well known.. Activated neutrophils are a possible pathogenesis of RP. Neutrophil activation induced by granulocyte colony-stimulating factor (G-CSF) may exacerbate RP. We studied the effects of recombinant human G-CSF on acute lung injury induced by thoracic irradiation using rats. Animals were divided into three groups: sham irradiation with saline control, irradiation alone, and irradiation with G-CSF. Actual irradiation was given as a single fraction of 16 Gy delivered to the right hemithorax. G-CSF at a dose of 12 microg/body was administered subcutaneously once a day from 14 to 18 days after actual irradiation. Lung injury was evaluated 21 days after irradiation by bronchoalveolar lavage (BAL) fluid findings and the lung wet/dry weight (W/D) ratio. Neutrophil and lymphocyte counts in BAL fluid and the W/D ratio were significantly increased in the irradiation alone and the irradiation with G-CSF groups compared with those of the sham irradiation + saline control group. However, there was no significant difference observed between the irradiation alone and irradiation with G-CSF groups. In conclusion, this study suggests that postradiation administration of G-CSF does not exacerbate acute lung injury induced by thoracic irradiation in rats.

Interactions of regional respiratory mechanics and pulmonary ventilatory impairment in pulmonary emphysema: assessment with dynamic MRI and xenon-133 single-photon emission CT

STUDY OBJECTIVES

Dynamic MRI and (133)Xe single-photon emission CT (SPECT) were used to directly evaluate the interaction of regional respiratory mechanics and lung ventilatory function in pulmonary emphysema.

METHODS

Respiratory diaphragmatic and chest wall (D/CW) motions were analyzed by sequential MRI of fast-gradient echo pulse sequences during two to three respiratory cycles in 28 patients with pulmonary emphysema, including 9 patients undergoing lung volume reduction surgery (LVRS). The extent of air trapping in the regional lung was quantified by the (133)Xe retention index (RI) on three-dimensional (133)Xe SPECT displays.

RESULTS

By contrast to healthy subjects (n = 6) with regular, synchronous D/CW motions, pulmonary emphysema patients showed reduced, irregular, or asynchronous motions in the hemithorax or location with greater (133)Xe retention, with significant decreases in the maximal amplitude of D/CW motions (MADM and MACWM; p < 0.0001 and p < 0.05, respectively). The removal of (133)Xe retention sites by LVRS effectively and regionally improved D/CW motions in nine patients, with significant increases in MADM and MACWM (p < 0.01 and p < 0.001, respectively). In a total of 40 studies of the 28 patients including post-LVRS studies, normalized MADM and MACWM correlated with percent predicted FEV(1) (r = 0.881, p < 0.0001; and r = 0.906, p < 0.0001, respectively), and also with (133)Xe RI in each hemithorax (r = -0.871, p < 0 0.0001; and r = -0.901, p < 0 0.0001, respectively.)

CONCLUSIONS

This direct comparison of regional respiratory mechanics with lung ventilation demonstrated a close interaction between these impairments in pulmonary emphysema. The present techniques provide additional sensitivity for evaluating pathophysiologic compromises in pulmonary emphysema, and may also be useful for selecting resection targets for LVRS and for monitoring the effects.

A preliminary study of discrimination among the components of small pulmonary nodules by MR imaging: correlation between MR images and histologic appearance

PURPOSE

To investigate whether magnetic resonance (MR) imaging depicts the internal characteristics of small pulmonary nodules.

METHODS

We reviewed MR images of 39 surgically resected pulmonary nodules 3 cm or less and compared the components within the nodules. In 22 malignant nodules, eight histologic components were characterized by signal and enhancement patterns on MR images.

RESULTS

MR images obtained from any single sequence discriminated all components in 26 (67%) nodules, whereas the combination of images from various sequences allowed discrimination in 35 (90%). Fourteen of 16 components of aggregated tumor cells showed marked early enhancement. Although fibrotic and necrotic components showed no or slight early enhancement, nine of 10 fibrotic components showed hypointensity and six of seven necrotic components showed hyperintensity on T2-weighted images. Component characterization in eight histologies by MR imaging was possible in 71-100%.

CONCLUSION

Our study demonstrated that MR imaging offers the possibility of high tissue-contrast resolution in small pulmonary nodules.

Impaired respiratory mechanics in pulmonary emphysema: evaluation with dynamic breathing MRI

To evaluate impaired respiratory mechanics in pulmonary emphysema, dynamic breathing magnetic resonance imaging (BMRI) was acquired with fast-gradient echo pulse sequences at fixed thoracic planes over two to three slow, deep respiratory cycles in 6 controls and 28 patients with pulmonary emphysema including 9 patients undergoing lung volume reduction surgery (LVRS). Respiratory motions of the diaphragm and chest wall (D/CW) were assessed by a cine-loop view, a fusion display of maximal inspiratory and expiratory images, and the time-distance curves. By contrast with normal subjects with regular synchronous D/CW motions, the patients frequently showed reduced, irregular, or asynchronous motions, with significant decreases in the maximal amplitude of D/CW motions (MAD and MACW), and the length of apposition of the diaphragm (LAD) (P < 0.0001, P < 0.001, P < 0. 01, respectively). After LVRS, nine patients showed improvements in D/CW configuration and mobility, with significantly increased MAD, MACW, and LAD (P < 0.01, P < 0.0001, and P < 0.05, respectively). In 40 studies of 28 patients including the post-LVRS examinations, the normalized MAD and MACW significantly correlated with %FEV(1) (r = 0. 881 and r = 0.906; P < 0.0001, respectively). BMRI seems useful for noninvasively and directly assessing the impaired respiratory mechanics associated with abnormal ventilation in pulmonary emphysema, and also for monitoring the effects of LVRS. J. Magn. Reson. Imaging 1999;10:510-520.

Hepatocellular carcinoma: association with increased iron deposition in the cirrhotic liver at MR imaging

PURPOSE

To determine whether the frequency of hepatocellular carcinoma (HCC) in patients with cirrhosis is affected by hepatic iron deposition as detected with magnetic resonance (MR) imaging.

MATERIALS AND METHODS

In a retrospective search of MR imaging and histopathology records, 196 patients with histopathologically proved cirrhosis and with (n = 80) or without (n = 116) HCC who underwent T2-weighted conventional or fast spin-echo and gradient-echo (GRE) (echo time > or = 6.0 msec) imaging were identified. MR images were qualitatively and quantitatively evaluated for diffuse hepatic iron deposition and siderotic regenerative nodules to assess their correlation with the presence of HCC.

RESULTS

Hepatic parenchymal iron deposition was seen in 79 (40%) patients, and iron deposition in regenerative nodules was seen in 71 (36%) at MR imaging. The mean signal intensity ratio of GRE images in patients with hepatic iron deposition was significantly lower than that in patients without it (P < .001). The frequency of HCC in patients with iron deposition in regenerative nodules (52% [37 of 71 patients]) was significantly higher (P = .015) than that in patients without iron in regenerative nodules (34% [43 of 125 patients]).

CONCLUSION

The occurrence of HCC may be associated causally with iron deposition in regenerative nodules in patients with cirrhosis. MR imaging can enable detection of iron deposition in regenerative nodules as a possible risk factor for the development of HCC.

High-resolution contrast-enhanced MRI of the uterus with a phased-array multicoil

High-resolution contrast-enhanced dynamic MRI of the uterus can be performed with the combination of a phased-array multicoil and fast GE techniques. This technique can improve the ability to visualize normal anatomy of the uterus and periuterine tissues, including vascular structures and pelvic ligaments, and to detect pathologic processes of the uterus and determine their extent.

Differential diagnosis of hepatic tumors with delayed enhancement at gadolinium-enhanced MRI: a pictorial essay

Hepatic lesions with delayed enhancement are sometimes encountered on gadolinium-enhanced MRI of the liver. This study illustrates the varied appearances of several pathologic entities with delayed enhancement, including hepatic hemangioma, hepatic metastases, intrahepatic cholangiocarcinoma, focal nodular hyperplasia, hepatic abscess, hepatocellular carcinoma, and hepatocellular carcinoma after transcatheter arterial chemoembolization, and presents the utility of arterial-phase dynamic MRI in the differential diagnosis of these lesions. Possible causes of these delayed enhancements are also discussed.

Gallbladder disease: appearance of associated transient increased attenuation in the liver at biphasic, contrast-enhanced dynamic CT

PURPOSE

To evaluate the frequency, location, and appearance of transient increased attenuation in the liver during arterial-phase helical or incremental computed tomography (CT) in patients with gallbladder disease without hepatic extension.

MATERIALS AND METHODS

Findings in dynamic CT examinations in 31 patients with surgically proved gallbladder disease not extending into the liver and in 31 control patients without gallbladder disease were retrospectively reviewed and correlated with findings in other imaging examinations.

RESULTS

Areas of transient increased hepatic attenuation (n = 27) were identified in 22 of 31 patients with gallbladder disease and in only one of 31 control patients. The difference in these findings was statistically significant (P < .001). In the 27 areas of transient increased hepatic attenuation, these findings were categorized as curvilinear or nodular attenuation adjacent to the gallbladder fossa in 13 (48%), segmental or subsegmental attenuation in segment IV and/or V in seven (26%), lobar attenuation in the left lobe (segments II-IV) in four (15%), and nodular attenuation seen as an early enhancing "pseudolesion" in segment IV in three (11%). Hepatic angiography performed in 10 of the 22 patients showed early depiction of the dilated cystic vein (n = 8) and direct communication with the portal branches (n = 2).

CONCLUSION

Transient increased attenuation in the liver had a variable appearance at dynamic arterial-phase CT in most patients with gallbladder disease. This attenuation was most likely due to increased blood flow from the hepatobiliary system.

CT of acquired abnormalities of the portal venous system

Computed tomography (CT), including biphasic contrast material-enhanced helical dynamic scanning and three-dimensional CT angiography, is useful in evaluating acquired abnormalities of the portal venous system. At contrast-enhanced CT, portal venous thrombus usually manifests as low-attenuation intraluminal lesions combined with enlargement of the affected portal vein. Cavernous transformation, a masslike network of intertwined veins that provides an alternative pathway for a stenosed or occluded portal vein, is depicted as multiple, periportal vascular structures. At helical dynamic CT, arterioportal shunts manifest as early enhancement of the affected portal vein, transient hyperperfusion abnormalities with lobar or segmental distribution, or transient wedge-shaped enhancement peripheral to the tumor. In patients with portosplenic venous invasion by malignant neoplasms, peripancreatic or perigastric veins may dilate if they function as hepatopetal collateral veins. In patients with portal hypertension, a variety of hepatofugal collateral pathways can develop, including esophageal, paraesophageal, coronary gastric, inferior phrenic, paraumbilical, abdominal wall, splenorenal, gastrorenal, retrocaval, and mesocaval collateral pathways. An understanding of the varied CT appearances of acquired abnormalities of the portal venous system will allow more definitive diagnosis and help avoid false diagnosis of disease.

Biphasic contrast-enhanced multisection dynamic MR imaging of the liver: potential pitfalls

Biphasic contrast material-enhanced dynamic magnetic resonance (MR) imaging is an important technique for evaluating liver disease. However, several potential diagnostic pitfalls may be encountered, including lobar, segmental, subsegmental, and subcapsular hyperperfusion abnormalities; early-enhancing pseudolesions, particularly in the medial segment of the left hepatic lobe; heterogeneous hyperperfusion abnormalities throughout the liver; and hypointense pseudolesions due to vascular artifacts, unenhanced hepatic vessels, partial volume artifacts, magnetic susceptibility artifacts, and regenerative nodules in cirrhosis. These abnormalities sometimes have appearances similar to those of true lesions or tumor spread to the surrounding liver parenchyma on arterial-dominant phase dynamic MR images. In most cases, however, no corresponding abnormalities are seen with other pulse sequences or on delayed-phase MR images. In addition, hyperperfusion abnormalities due to readily recognizable causes are often found in characteristic locations and thus can be differentiated from true tumors. An understanding of the causes of these potential pitfalls and how to avoid them will help radiologists understand and correctly interpret images.

Hepatic parenchymal hyperperfusion abnormalities detected with multisection dynamic MR imaging: appearance and interpretation

On arterial-dominant-phase images in multisection dynamic MR imaging, early-enhancing areas that are perfusion abnormalities rather than tumor deposit are sometimes encountered. The purpose of this article was to determine the frequency, location, and appearance of these hepatic parenchymal hyperperfusion abnormalities and to discuss possible causes of these abnormalities. Multisection dynamic MR images obtained in 415 patients with suspected hepatobiliary diseases were reviewed for the presence of hyperperfusion abnormalities. A total of 96 hyperperfusion abnormalities were identified in 88 (21%) of 415 patients. They were characterised from their shape, distribution, or location as lobar or segmental (n = 36 [38%]), subsegmental (n = 32 [33%]), or subcapsular (n = 28 [29%]) hyperperfusion abnormalities. Presumable etiologies were considered as follows: (a) compression, obstruction, or ligation of the portal vein; (b) siphoning effect by tumor; (c) aberrant cystic venous drainage; (d) percutaneous ethanol injection; (e) percutaneous needle biopsy; (f) rapid drainage by the subcapsular vein; or (g) cirrhosis or unknown. A significant percentage of patients had hepatic hyperperfusion abnormalities. Familiarity with these hyperperfusion abnormalities on multisection dynamic MR images is important to prevent false-positive diagnoses.

Liver neoplasms: diagnostic pitfalls in cross-sectional imaging

The appearances of most common liver neoplasms at computed tomography (CT) and magnetic resonance (MR) imaging have been established. However, there are considerable overlaps in the appearances of various pathologic entities. Certain hepatic lesions, such as hepatic hemangioma, adenoma, focal nodular hyperplasia, intrahepatic cholangiocarcinoma, metastases, hepatocellular carcinoma, regenerative nodules, adenomatous hyperplastic nodules, abscess, and hepatocellular carcinoma treated with transcatheter arterial chemoembolization, can have unusual characteristics at CT and MR imaging that may lead to misinterpretation. Dynamic helical CT and double-phase multisection dynamic MR imaging techniques may be helpful in differentiating between these entities because hemodynamics of the lesion can be evaluated by obtaining both arterial-phase and delayed-phase images. It is important for radiologists to be aware of these uncommon appearances of liver neoplasms. Familiarity with these varied CT and MR imaging features will permit a more accurate diagnosis and aid in avoidance of a false diagnosis.

Enhanced MR imaging of the liver after ethanol treatment of hepatocellular carcinoma: evaluation of areas of hyperperfusion adjacent to the tumor

OBJECTIVE

In the arterial phase of dynamic contrast-enhanced MR images, we observed areas of increased contrast enhancement adjacent to hepatocellular carcinomas treated by percutaneous ethanol injection. The purpose of this study was to assess the frequency, appearance, and location of this hyperperfusion abnormality. It is important not to mistake this finding for other pathologic conditions.

SUBJECTS AND METHODS

Multisection dynamic MR images obtained in 33 consecutive patients with hepatocellular carcinoma treated with percutaneous ethanol injection were reviewed. Hepatic parenchymal hyperperfusion abnormalities were diagnosed when areas of early enhancement were seen in the hepatic parenchyma adjacent to the treated tumor. The location, appearance, and frequency of the findings were recorded.

RESULTS

Hepatic parenchymal hyperperfusion abnormalities were observed in 15 (45%) of the 33 patients on arterial-dominant-phase images. Of these 15 patients, 10 (67%) had MR imaging within 1 month after percutaneous ethanol injection. Hyperperfusion abnormalities were located in liver parenchyma adjacent to the lesion with wedge-shaped appearances. In two patients, early opacification of the peripheral portal branch was seen within the area of hyperperfusion abnormalities.

CONCLUSION

Hepatic hyperperfusion abnormalities are commonly seen adjacent to a treated hepatocellular carcinoma on contrast-enhanced MR images. Awareness of this hyperperfusion abnormality, which is caused by increased blood flow after percutaneous ethanol injection, is important because such a finding may be misinterpreted as another pathologic condition such as tumor progression or tumor thrombosis of the portal vein branches.

Therapeutic efficacy of transcatheter arterial chemoembolization for hepatocellular carcinoma: MRI and pathology

OBJECTIVE

Our goal was to evaluate the usefulness of multisection dynamic MRI with gadopentetate dimeglumine in the assessment of the therapeutic efficacy of transcatheter arterial chemoembolization (TAE) with iodized oil for hepatocellular carcinomas (HCCs).

MATERIALS AND METHODS

Findings on multisection dynamic MRI images were compared with gross appearance and histologic findings in 13 patients with HCCs after TAE with iodized oil. Arterial dominant phase images of the entire liver were obtained 20 s after the start of administration of gadopentetate dimeglumine.

RESULTS

In 3 of the 13 patients, no enhancing areas within the tumors were detected. In the remaining 10 patients, enhancing portions were detected within the tumor on arterial dominant phase images. Histologically, viable tumor cells were present in the rapidly enhancing portions, while necrotic tissues were present in nonenhancing areas, irrespective of the accumulation of iodized oil on CT scans. However, in one patient in whom no enhancing portion was seen in the tumor, a small number of viable tumor cells within the capsule were identified on pathologic examination.

CONCLUSION

Multisection dynamic MRI is helpful for evaluating the therapeutic efficacy of TAE with iodized oil for HCCs by revealing the hemodynamics of the tumor irrespective of accumulation of iodized oil.

[Experimental and clinical evaluation of 99mTc-HMPAO as a sensitive marker for chemical lung injury]

To investigate whether 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) can be a sensitive marker of lung injury, an animal model of lung injury was designed in the rabbits using the injection of a low dose (0.05 ml/kg) of oleic acid. In the injured rabbit lungs, electron microscope revealed morphologic changes localized in the microvascular endothelium (edematous change), although their chest radiographies and light microscope did not show any significant changes compared to the controls. In these situations, 99mTc-HMPAO showed a diffusely, high pulmonary uptake, which occurred rapidly within the first 1 min after the injection. Clinically, the lungs in the patients who had been administered with cytotoxic anti-cancer drugs showed a significantly higher 99mTc-HMPAO uptake compared to the controls. These findings indicate that 99mTc-HMPAO may have potential as a sensitive marker of chemical lung injury.

Hexahydro-1H-1-pyrindines from acid rearrangement of 9-alkylidene-5-(m-methoxyphenyl)-2-methylmorphans. A new structural type of narcotic antagonists

9-Methylene- and 9-ethylidene-5-(m-methoxyphenyl)-2-methylmorphans (1, 2) and refluxing 48% HBr have given rearrangement products 3 and 4, respectively. The structure of 4 [4a-ethyl-2,4a,5,6,7,7a-hexahydro-4-(3-hydroxyphenyl)-1-methyl-1H-1- pyrindine] was determined by X-ray crystallography and that of 3 [1,4a-dimethyl-2,4a,5,6,7,7a-hexahydro-4-(3-hydroxyphenyl)-1-methyl-1H- pyrindine] follows from analogy and NMR data. Compounds 3 and 4 are opioid antagonists of about the potency of nalorphine in the tail-flick vs. morphine assay and precipitate a complete abstinence syndrome in morphine-dependent monkeys. Both are nearly devoid of antinociceptive activity and they have about 0.025 times the affinity of nalorphine for the mu opioid receptor.

Pharmacological effects of 1,2,3,5,6,10b-hexahydropyrido[2,3g]indolizine, a bridged-nicotine analog

The racemate of a bridged-nicotine (BN) analog was synthesized and resolved into its enantiomers for pharmacological comparisons to (+)- and (-)-nicotine. The EC50 values for (-)- and (+)-nicotine and (-)- and (+)-BN were 4, 170, 53 and 400 microM, respectively, for producing contractions of guinea-pig ilea. (-)-Nicotine was an effective antinociceptive agent in the mouse tail-flick procedure at i.v. doses of 0.1-0.3 mg/kg, whereas the isomers of BN failed to alter tail-flick response in doses up to 5 mg/kg. (-)-Nicotine (0.01-0.3 mg/kg, i.v.) increased blood pressure and decreased heart rate in anesthetized rats. Neither (+)- nor (-)-BN altered blood pressure and heart rate in rats in this dosage range. At doses of 3-100 mg/kg, (+)-BN produced an increase in blood pressure without changing heart rate, while (-)-BN decreased both blood pressure and heart rate. Bridging the pyrrolidine and pyridine rings decreased biologic activity and did not result in stereoselectivity greater than that observed with (+)- and (-)-nicotine. It appears that there may be subpopulations of nicotine receptors to which the isomers of BN do not interact.

Agonist-Antagonist Actions and Stereoselectivity of Optical Pairs of Some N-substituted α-N-Normetazocines

alpha-(-)-, (+)-, and (+/-)-N-4-Methylpentyl-, (-)- and (+)-N-cis-3-chloroallyl-, and (-)- and (+)-N-propynyl-N-normetazocine (I, II, and III, respectively) have been prepared from alpha-(-)-, (+)-, and (+/-)-N-normetazocine (IV) and tested for antinociceptive activity in mice and in morphine-dependent rhesus monkeys. The results obtained with Ia and b somewhat resemble the results obtained with the corresponding phenazocine isomers, whereas those observed with IIa and b more nearly correspond with those reported for (+)- and (-)-N-allyl-N-normetazocine (SKF 10,047; NANM). The propynyl isomers (IIIa and b) display profiles of activity more closely like the corresponding isomers of metazocine. Evidence is considered which suggests that some of the (+)-isomers merit closer scrutiny in animal and human studies.

9α- and 9β-Hydroxyphenylmorphans

Platinum-oxide hydrogenation of 5-m-methoxyphenyl-2-methyl-9-oxomorphan (I) gave the 9 alpha-hydroxy racemate (II) whose phenolic analogue (III) is a strong antinociceptive agent, fully supportive of morphine dependence in rhesus monkeys. The di-O-acetyl derivative (VI) of III was similar to III in its profile of activity. The diastereoisomer of III (VII), obtained by hydrogenation of the methobromide of I (IV), extrusion of methyl bromide, and O-demethylation of the resultant free base (VIII), was almost inactive antinociceptively and did not suppress withdrawal symptoms in morphine-dependent monkeys. The orientation of the C-9 hydroxyl groups was deduced from spectral data and by analogy.

Racemic and optically active 2,9-dimethyl-5-(m-hydroxyphenyl)morphans and pharmacological comparison with the 9-demethyl homologues

2,9 alpha-Dimethyl-5-(m-hydroxyphenyl)morphan (3a) has been synthesized from 5-(m-methoxyphenyl)-2-methyl-9-oxomorphan (4) and resolved into its enantiomers (+)-3a and (-)-3a. The assigned alpha-orientation of the 9-methyl group was derived from studies of induced NMR shifts using Eu(fod)3-d27. Compound (+)-3a has inappreciable agonist (antinociceptive) activity in mice, and (-)-3a shows codeine-like potency in the hot-plate and writhing tests only. The 9-demethyl homologues, (+)-1 and (-)-1, are strong agonists, about as potent as morphine in these tests as well as in the tail-flick assay. The racemic compound 3a and (+)-3a, but not (-)-3a, exhibit low-potency, narcotic-antagonist activity in mice (tail-flick test, vs. morphine). All three, however, precipitate abstinence in nonwithdrawn, morphine-dependent rhesus monkeys. Monkey studies with the 9-demethyl homologues confirmed earlier results showing that (+)-1, suppressing abstinence in withdrawn animals, has high physical dependence capacity, while (-)-1 has none. Instead, (-)-1 precipitates abstinence in nonwithdrawn animals. Studies in rats and isolated organs (guinea pig ileum and mouse vas deferens) and receptor-binding assays confirm the quite different opioid-action profiles of (+)-1 and (-)-1, which thus might interact with different opioid receptors. Catalytic hydrogenation of the methiodide (7) of 5 gave, instead of the expected epimer of 3a, ring-opened compound 8.

Antinociceptive action of nicotine and its methiodide derivatives in mice and rats

Three quaternary methiodides of nicotine were prepared and tested for antinociceptive activity in the mouse tail-flick, mouse phenylquinone and rat tail-flick tests. Following peripheral administration, all three methiodides were inactive in the mouse and rat tail-flick procedures, whereas nicotine was active in both tests, which suggested that nicotine was acting centrally. Quaternization of nicotine did not eliminate antinociceptive activity as demonstrated by the intraventricular injection of the methiodides in mice. Nicotine pyrrolidine and bis methiodides were somewhat more potent than nicotine, whereas nicotine pyridine methiodide was considerably less potent than nicotine in the tail-flick procedure. Systemically administered nicotine pyrrolidine methiodine was approximately one-third as active as nicotine in the mouse phenylquinone test; nicotine pyridine methiodide and nicotine bis methiodide were 100 and 300 times less active, respectively. Hexamethonium partially blocked nicotine and nicotine pyrrolidine methiodide, whereas mecamylamine blocked nicotine completely but nicotine pyrrolidine methiodide partially. Nicotine may have both central and peripheral actions in the mouse phenylquinone test, whereas nicotine pyrrolidine methiodide may have both nicotine and non-nicotine like antinociceptive activity. The radiolabelled methiodides were synthesized and their disposition in body tissues studied. The methiodides were found to penetrate brain poorly (plasma-to-brain ratios greater than 20). The methiodides were metabolized to nicotine to a small extent. This metabolism occurred to a greater extent in mice than in rats.

In vitro metabolism of 1-phenyl-1-cyclohexene, a pyrolysis product of phencyclidine

The in vitro metabolism of 1-3H-phenyl-1-cyclohexene (3H-PC) was studied in a crude microsomal preparation from mouse livers. The major routes of metabolism were allylic hydroxylation, oxidation of the allylic alcohol, and epoxidation-hydrolysis. The following metabolites were identified by comparison with reference compounds: 1-phenyl-1-cyclohexen-3-ol (major metabolite), 1-phenyl-1-cyclohexen-3-one (PC-3-one) (major), 1-phenyl-1-cyclohexen-6-ol (minor), 1-phenyl-1-cyclohexen-6-one (minor), and 1-phenylcyclohexane-1,2-diol (PC-1,2-diol) (minor). An additional metabolite, present in abundant quantities, was formed as a result of both allylic hydroxylation and epoxidation-hydrolysis. This triol contained hydroxyl groups at positions 1 and 2 of the cyclohexane ring but the position of the third hydroxyl group could not be established. PC-3-ol and PC-3-one were found to be somewhat more potent than PC in the inverted-screen test, whereas PC-1,2-diol was less effective. However, all three metabolites were considerably less active than PCP in this test.