The action of oxytocin originating in the hypothalamic paraventricular nucleus on mitral and granule cells in the rat main olfactory bulb

The effects of electrical stimulation of the hypothalamus paraventricular nucleus on the spontaneous firing of mitral and granule cells in the main olfactory bulb were examined in ovariectomized female rats under urethane anaesthesia. High-frequency stimulation (0.5-1.0 mA, 10-20 pulses at 100 Hz) of the paraventricular nucleus produced inhibitory responses in 80% of mitral cells tested and excitatory responses in 74% of granule cells tested, with latencies ranging from 2 to 150 s. Both responses were blocked by infusions into the olfactory bulb of [d(CH2)5, Tyr(Me)2]ornithine-vasotocin (10 pmol), an oxytocin antagonist, and mimicked by intracerebroventricular infusions (0.2 or 0.4 nmol) or microiontophoretic applications of oxytocin but not by intracerebroventricular infusions of vasopressin (1 or 2 nmol). Infusions of 0.5% lignocaine, a local anaesthetic, into either the medial olfactory tract or the medial forebrain bundle failed to block the responses of mitral and granule cells to the stimulation. Unilateral transections at various levels between the bulb and the paraventricular nucleus also failed to block the responses. There were cases in which significant responses of mitral and granule cells to the stimulation required 60 or more pulses after the lignocaine infusions or transections, however. These results suggest that oxytocin originating in the hypothalamic paraventricular nucleus reaches the olfactory bulb following its release partly into the cerebrospinal fluid and acts to decrease olfactory processing.

Gallbladder cancer associated with cholesterosis

We report herein two cases of carcinoma in situ of the gallbladder associated with cholesterosis. The patient in case 1 was an 81-year-old man who underwent a cholecystectomy for cholelithiasis. The resected specimens revealed gallbladder cancer in the fundus which was diagnosed histologically as mucinous carcinoma. Other findings included 13-mm, 12-mm, and 5-mm polypoid lesions in the neck of the gallbladder which macroscopically appeared to be cholesterol polyps, but histologically demonstrated carcinoma in situ with cholesterosis. The patient in case 2 was a 76-year-old man in whom ultrasonography revealed a highly echogenic, elevated lesion in the gallbladder. Cholecystectomy was performed, and a 33 x 28-mm papillary, elevated lesion with cholesterosis was resected from the neck of the gallbladder. Histologically, this was demonstrated to be papillary adenocarcinoma in situ with cholesterosis surrounded by glandular dysplasia. The distribution of the carcinomas and cholesterosis in both of these patients suggests that the adenoma or carcinoma of the gallbladder had occurred first. Then, the tumor epithelium absorbed cholesterol from the bile, and foamy cells were produced. Thus, when treating cholesterol polyps, it should be remembered that it is often difficult to distinguish between cholesterol polyp and gallbladder cancer with cholesterosis.

[Serological assay for diagnosis of verotoxin-producing Escherichia coli (VTEC) infection in the patients with diarrhea]

A total of 239 serum samples from 136 persons were used for bacterial agglutination assay (BA) against predominant three O-antigens of VTEC. All VTEC isolates from stools of 30 patients were only O157:H7 serotype (these patients are called group I). The levels of positive BA antibody titers (over 1:160) to O157-antigen were recognized in each patients as follows. The VTEC isolated patients with HUS or without HUS in group I were all of 13 (100%) and 14 (82.4%) in 17 patients, respectively. And 21 (65.6%) patients of group II (HUS patients with stool negative cultures, or stool cultures were not performed in 32 patients), and 6 (15.0%) patients of group III (family members of group I and II; 40 persons), were also recognized. In group IV (patients with diarrhea due to other pathogen than VTEC; 11 patients), and V (clinically healthy persons; 23 persons), none were recognized as positive BA antibody titers. All patients in the group II except one who had a positive BA antibody titer to O111, were not recognized to O111 and O26. A few VTEC-positive patients without gastrointestinal syndrome did not have significant agglutinating titers to O157-antigen on the days after VTEC isolation. However, almost all patients with diarrhea due to VTEC and HUS, and with VTEC but no HUS, had a level of positive BA antibody titer on the 5 day after onset of diarrhea. These results suggest that this serological assay is a very simple and useful tool for diagnosis of VTEC infection when VTEC are not detected by culture method due to antimicrobial treatment, or due to the lapse of many days after onset of diarrhea.

[Evaluation of preoperative blood preparation and blood consumption for implementation of type and screen and maximum surgical blood order schedule]

We analyzed preoperative blood preparation and intraoperative blood transfusion in Kagawa Prefectural Central Hospital and evaluated the effectiveness of maximum surgical blood order schedule (MSBOS) and Type and Screen (T&S). Forty seven kinds of surgery were performed on 1,283 cases from May, 1991 to April, 1992. Transfusion was performed in 179 cases of them. All of 1,884 units of blood that had been prepared, were crossmatched and 1,078 of them were actually transfused. The Crossmatched to Transfused ratio (C/T ratio) was 1.71. If we adopted MSBOS and T&S in 13 elective surgery, 766 units of blood and labour work for preoperative blood preparation could have been saved. MSBOS and T&S are beneficial for efficient usage of blood transfusion in surgery.

Long-term histological evaluation of hydroxyapatite ceramics in humans

We have investigated the interface between bone and hydroxyapatite (HA) chronically implanted in man. By light microscopy, HA appeared to bind directly to bone without intervening fibrous tissue. By transmission electron microscopy, two patterns were noted: (1) HA either bound directly to bone; or (2) electron-dense material intervened between HA and bone. The orientation of bone collagen fibres likewise showed two patterns: (1) collagen fibres were oriented parallel to the HA; or (2) the fibres were aligned perpendicularly. We have observed similar binding properties of HA to the jaw bone of humans in vivo and in vitro.

A rat model of HTLV-I infection: development of chronic progressive myeloneuropathy in seropositive WKAH rats and related apoptosis

In seropositive HTLV-I carrier rats of the WKAH strain inoculated with 2 x 10(7) MT-2 cells at 3-6 months of age, chronic progressive myeloneuropathy, tentatively designated as HTLV-I-associated myelopathy (HAM) rat disease, occurred when the rats were 19-23 months old. Clinical and pathological findings were basically identical to those of seronegative HAM rats of the same strain neonatally inoculated with MT-2 cells. It appears that a high dose of MT-2 cells (10(8) cells) is more effective for the induction and acceleration of HAM rat disease. Seronegative and seropositive carriers of other strains (F344, ACI, and LEW), WKAH rats inoculated with HUT-78 (a human T cell line without HTLV-I infection), and untreated WKAH rats at comparable ages did not develop HAM rat disease, thereby indicating that development of this disease is caused by HTLV-I infection and is under strict genetic restriction of the host strain. Chronological examination of HAM rat disease induced by 10(7) MT-2 inoculation into newborn rats showed that the spinal cord lesion began to develop by 12 months of age. T cells were absent in the affected spinal cord throughout the disease process. There was morphological evidence of apoptotic death of oligodendrocytes in the affected spinal cord. Apoptosis was also confirmed by the specific nick end labeling of the nuclear fragmentation in situ, and the apoptotic oligodendrocytes confined to the demyelinating foci, and the number of apoptotic cells positively correlated with severity of the spinal cord lesion.(ABSTRACT TRUNCATED AT 250 WORDS)

[Polymerase chain reaction (PCR) method for the detection of Salmonella by using Chelex resin after enrichment culture]

Salmonella has been implicated as a important pathogen associated with acute gastroenteritis or food borne diseases in humans. Rapid and accurate diagnostic tests for Salmonella are needed by both the food industry and clinical laboratories. A pair of oligonucleotide primers from the phoE gene was used to develop a polymerase chain reaction (PCR) procedure to detect Salmonella spp. When Chelex-extracted DNA from the SBG enrichment culture were used as templates for the PCR amplification (E-Chx), the positive results were obtained with a few cells of Salmonella. This highly specific and sensitive technique gave an efficiency of 1.2 times (73 samples were positive) when tested against conventional culture method (62 samples were positive) using 125 fecal samples stored at 4 degrees C for 1-16 months. Based on the results obtained in this study, it appears that the enrichment-PCR method (E-Chx) using Chelex-extracted DNA described here can be useful to screen a large number of samples such as foods or environmental specimens for contamination of Salmonella.

Effective induction of pregnancy block by electrical stimulation of the mouse accessory olfactory bulb coincident with prolactin surges

Electrical stimulation (0.33 Hz, 0.2 mA) applied bilaterally to the accessory olfactory bulb (AOB) of newly mated female mice revealed that stimulation for 4 h was sufficient to produce pregnancy block providing stimulation is given for two separate 2-h periods coincident with prolactin surges. Stimulation for two 1-h periods coincident with prolactin surges or two 2-h periods between prolactin surges was without effect. These results indicate that electrical stimulation of the AOB can faithfully reproduce pheromone-induced pregnancy block and support the view that prolactin is the hormone mainly responsible for the olfactory block to pregnancy.

[Analysis of HAM rat disease developed in HTLV-I carrier rat as an animal model of HAM/TSP in human]

Human T cell leukemia virus type I (HTLV-I) can be transmitted into several inbred strains of rats. Adult rats inoculated with HTLV-I immortalized human T cell line MT-2 at 8-37 weeks of age become seropositive HTLV-I carrier rats. Seropositive HTLV-I carrier rats of WKAH strain developed myelopathy similar to HAM/TSP (HTLV-I associated myelopathy/Tropical spastic paraparesis), designated as HAM rat disease. Neuropathological and immunohistochemical features of the affected spinal cord showed symmetrical white matter degeneration characterized by loss of myelin, vacuolar degeneration, infiltration with foamy macrophages and astrocytic gliosis. Lymphocytic infiltration was virtually absent throughout the disease process, and apoptotic cells were observed in the affected spinal cord. Clinical findings and pathological changes in seropositive HAM rats were, in general, milder than findings in seronegative HAM rats as previously described. Provirus genome in the affected spinal cord was evident in 1 of 2 seropositive HAM rats by polymerase chain reaction, but localization of HTLV-I antigen could not be detected by immunohistochemical staining. The collective evidence suggests that development of HAM rat disease is under strict genetic restriction of the host strain, and the primary cause is not mediated by immunological process with effector T cells as suggested in human HAM/TSP, and there seems to be a direct or indirect neurotoxicity for oligodendrocytes mediated by HTLV-I infection.

Total intravenous anesthesia. Midazolam-fentanyl vs enflurane-nitrous oxide

This study was done to compare the hemodynamics, serum catecholamine levels and postoperative analgesia in total intravenous anesthesia with inhalation anesthesia. Thirteen patients for elective upper abdominal surgery, aged from 40 to 75 years, were studied. In the total intravenous anesthesia group (TIVA group, 7 patients), anesthesia was induced with 0.3 mg.kg-1 midazolam and maintained with 0.68 mg.kg-1.hr-1 midazolam for 15 minutes followed by 0.125 mg.kg-1.hr-1. Fentanyl was also administered as necessary. In the inhalation anesthesia group (inhalation group, 6 patients), anesthesia was induced with 5 mg.kg-1 thiamylal and maintained with 0.5-2.0% enflurane and 66% nitrous oxide in oxygen. In the TIVA group, the blood pressure and heart rate were as stable as those in the inhalation group. The serum concentration of catecholamines in the TIVA group rose significantly 60 minutes after intubation, in particular, the serum epinephrine level was higher than in the inhalation group. The time for extubation, respiratory rate and PaCO2 were not different between the two groups. The postoperative analgesic duration in the TIVA group was significantly longer than that in the inhalation group. The elimination half-life of midazolam was 1.675 +/- 0.281 hours in the TIVA group. In this study, TIVA failed to suppress the elevation of serum catecholamine levels, but it achieved stable hemodynamics during upper abdominal surgery and enough postoperative analgesia without affecting the extubation time, the respiratory conditions and the elimination half-life of midazolam.

[Induction of anesthesia with midazolam and thiamylal]

Midazolam has a slow onset of action, while thiamylal causes pain on injection and circulatory changes. To compensate for these drawbacks, the usefulness of a combination of midazolam and thiamylal in anesthesia induction was studied. The combination method was compared to the induction with single use of thiamylal in 40 patients (20 patients in each group). The combination of 0.2 mg.kg-1 of midazolam and 1.9 mg.kg-1 of thiamylal showed a shorter onset of action than the 4-5 mg.kg-1 of thiamylal. Pain on injection was observed in 5 cases of thiamylal group but in no cases of combination group. The changes in blood pressure, heart rate and rate pressure product were obviously smaller in combination group than in thiamylal group. Although the recovery time from anesthesia of combination group (13.2 minutes) was longer than that of thiamylal group (10.5 minutes), this was not clinically important. It is concluded that anesthesia induction with the combination of midazolam 0.2 mg.kg-1 and thiamylal 1.9 mg.kg-1 is more useful than that of thiamylal alone.

[Concentrations of haptoglobin and free hemoglobin in preserved whole blood]

In bank blood, red blood cells are destroyed and free hemoglobin increases during preservation. Concentrations of haptoglobin and free hemoglobin were measured in 73 packages of preserved whole blood which had been kept for various periods, 1 to 21 days. Those blood samples were divided into 7 groups depending on preserved period, 1 to 3, 4 to 6, 7 to 9 days, and so on. Total haptoglobin decreased to less than 100 mg.dl-1 in the blood preserved over 7 days. Total hemoglobin increased with the passage of preserved period. Free hemoglobin appeared in 40% or more of the blood preserved over 7 days and its concentration increased depending on preserved time. Free hemoglobin of 10 mg.dl-1 or more was detected in the blood preserved over 7 days. It is recommended that for massive blood transfusion the whole bank blood under 7 days of preservation should be used.

Effect of low-dose cyclosporin A on systemic lupus erythematosus disease activity

OBJECTIVE

To determine the effect of low-dose cyclosporin A (CSA) treatment on disease activity in systemic lupus erythematosus (SLE).

METHODS

All patients in the study had active disease as defined by at least the presence of a low CH50 level. Patients were initially given 3 mg/kg/day of CSA. Dosages were adjusted individually at every visit, according to both clinical and laboratory data.

RESULTS

Eleven women with SLE were enrolled in the study; 10 were evaluable. After 20 weeks of CSA treatment, the mean score for disease activity on the SLE Disease Activity Index decreased significantly, from 10.6 to 3.8 (P = 0.02). The titer of antinuclear antibodies decreased in 8 patients and the level of anti-DNA antibodies decreased in 5. Side effects included hypertension (40%), hypertrichosis (30%), gingival hypertrophy (10%), and a rise in the blood urea nitrogen level. Serum creatinine levels remained unchanged.

CONCLUSION

The favorable responses observed in our patients strongly suggest that low-dose CSA can reduce the disease activity of SLE.

[Differentiation of cholera-enterotoxin producing Vibrio strains by polymerase chain reaction]

The pathogenic factor of Vibrio cholerae that induces a severe watery diarrhea in humans is cholera enterotoxin (CT). We have earlier reported on the use of a specific polymerase chain reaction method (PCR) for confirmation of CT-production. In our results, a few CT-producing V. mimicus strains were detected by the method. Here we report on the PCR method using 2-primer sets in the same tube for differentiation of toxigenic V. cholerae (O1 and non-O1) and toxigenic V. mimicus. One primer pair is for CT-gene (ctx), and the other pair is for the toxR gene which regulates the ctx gene of V. cholerae. ToxR genes were detected in all CT-producing V. cholerae (both O1 and non-O1). There were no isolates of the ctx gene positive and toxR gene negative in all V. cholerae strains. On the other hand, V. mimicus strain has not recognized toxR genes except one strain which is similar to the character of V. cholerae. These results indicates that the CT-producing V. cholerae strains are regulated by the toxR gene, but the ctx gene of V. mimicus is controlled by another different genome from toxR of V. cholerae.

Centrally administered ouabain aggravates rapid-eye-movement-sleep-related bradyarrhythmias in freely moving rats

1. The effects of continuous infusions of ouabain on bradyarrhythmias (cardiac pauses for 0.5 s or longer) during sleep were examined in freely moving Wistar-Kyoto rats. 2. In a control group (n = 7), saline was infused into both the lateral ventricle and the femoral vein. In an intracerebroventricular (i.c.v.) ouabain group (n = 7), ouabain was infused centrally, such that each rat received three stepped doses of 1, 10, and 100 ng kg-1 h-1 for 3 days at each dose, while saline was infused systemically. In an intravenous (i.v.) ouabain group (n = 7), ouabain was infused systemically at the same doses as the i.c.v. ouabain received, while the simultaneous i.c.v. infusion of saline was carried out. 3. Three-day i.c.v. infusions of the three stepped doses of ouabain caused a dose-dependent increase in the frequency of bradyarrhythmias during rapid-eye movement (REM) sleep without affecting the time spent in REM sleep, arterial pressure, average heart rate, or the frequency of bradyarrhythmias during non-REM sleep. Intravenous ouabain or i.c.v. saline had no effects on the frequency of bradyarrhythmias. 4. Intrinsic CNS activity during REM sleep may be involved in the centrally mediated arrhythmogenic properties of ouabain during sleep.

[Pharmacokinetics of midazolam in patients with liver damage for hepatectomy]

Pharmacokinetics of midazolam in patients with liver damage for hepatectomy was compared to that in patients without liver injury for gastrectomy. Anesthesia was induced with midazolam 0.15 mg.kg-1 and fentanyl. Serum concentration of midazolam was measured at 30 minutes, 1, 2, 3, 4, 6 and 8 hours after midazolam injection. Serum midazolam levels were not significantly different between the two groups at any time. The elimination half-life of midazolam was about 3 times longer in hepatectomy group (24.2 hours) than in the group without liver injury (8.4 hours). Area under the curve of the serum midazolam concentration was larger in the group with liver damage than in the group without it. But distribution volume and clearance of midazolam were not different between the two groups probably because of more blood transfusion and bleeding in hepatectomy group. The recovery time from anesthesia in hepatectomy group was as long as that in the group without liver injury. The results suggest that in patients with liver damage for hepatectomy, the elimination of midazolam is prolonged but its effect is not.

[Clinical studies on renovascular hypertension with bilateral renal artery stenosis]

Clinical studies were performed on 7 renovascular hypertensive patients (3 male and 4 female, mean age 50.6 +/- 18.6) with bilateral renal artery stenosis. Duration of hypertension ranged from 2 months to 24 years (mean 6.1 +/- 8.2 years) before evaluation. All had stenosis or occlusion of both main renal arteries or these branches shown by arteriography. In 4 of the 7 patients atheromatous stenosis or occlusion was present; the remaining two had aortitis syndrome and one had fibromuscular hyperplasia. Of the 7 patients operated, two who had both negative renal renin study and ureteric catheterization study; one was failure after bilateral percutaneous transluminal angioplasty (PTA), and another one was improved after axillo-femoral bypass operation. In one patient with positive results of both studies an area of focal cortical atrophy was present in upper part of the left kidney. The patient, therefore, underwent partial nephrectomy the left kidney but failed to have decrease of blood pressure and was subsequently treated with antihypertensive medications. In the remaining four patients operated, two who had both positive renin and catheterization studies preoperatively were cured or improved after PTA in negative side and nephrectomy of positive side kidney. Other two patients with contradictory results of renin and catheterization studies underwent, PTA of the renal artery of the kidney with the highest renin levels. But their hypertension was maintained despite sufficient dilatation of the renal artery and PRA from the contralateral kidney was noted to be markedly increased after PTA. Therefore, nephrectomy of the contralateral nonfunctioning contracted kidney was performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Centrally administered ouabain aggravates central sleep apneas

The presence of endogenous digitalis-like factors in the central nervous system suggests their functional significance in the central nervous system. Three-day infusions of three-stepped doses of the digitalis agent ouabain (1-100 ng.kg body wt-1.h-1) into the lateral cerebral ventricle of freely moving rats caused a dose-dependent increase in the number of central-apneic episodes during rapid-eye-movement sleep without affecting the time spent in rapid-eye-movement sleep or basic respiratory rate. These results suggest that endogenous digitalis-like factors may be involved in the genesis of central sleep apneas.

Promoting effects of bile acid load on the occurrence of cholangiocarcinoma induced by diisopropanolnitrosamine in hamsters

This study was performed to clarify the promoting effects of primary or secondary bile acid load on the occurrence of cholangiocarcinoma, using Syrian golden hamsters. These hamsters received subcutaneously diisopropanolnitrosamine (DIPN) once weekly for 10 weeks, and simultaneously were given a standard pellet diet (control group) containing taurocholic acid (TCA group) or deoxycholic acid (DCA group). The rates of cholangiocarcinoma at 20 weeks were 23% in the control group, 60% in the TCA group and 59% in the DCA group. There were significant differences between the control and the TCA or DCA groups (p < 0.05). The rates of proliferation of bile ductules or hyperplasia of the bile duct epithelium and the bromodeoxyuridine labeling indices of bile duct epithelial cells were high in both groups treated with bile acids, compared with those in the control group. Regarding the composition of bile acids in the intraductal bile, the TCA and DCA groups revealed a decrease in primary bile acids and an increase in DCA. These results suggest that both TCA and DCA given orally promote the occurrence of DIPN-induced cholangiocarcinoma.

Heterogeneous characteristics of mitral cells in the rat olfactory bulb

The spontaneous firing activity of olfactory bulb mitral cells and their response to intrabulbar infusion of GABAA receptor antagonist bicuculline were studied in ovariectomized, urethane-anesthetized female rats. Mitral cells recorded in the absence of specific stimuli and nasal airflow displayed three distinct patterns of spontaneous firing: high-frequency bursts with relatively long silent periods; high-frequency bursts without accurately defined silent periods; continuous. Infusion of bicuculline (0.2 nmol) into the bulb yielded inconsistent results on spontaneous firing and its inhibition evoked by electrical stimulation of the lateral olfactory tract. Of 32 cells tested, the spontaneous firing rate increased for 24, decreased for 6, and was not altered for 2. Likewise, of 18 cells tested, the poststimulus inhibitory period shortened for 12, lengthened for 4, and not altered for 2. An increased dose (0.4 nmol) of bicuculline produced dose-response relationships simply without any reversal effect. These results suggest that the heterogeneity of mitral cells exists in the context of local interneuronal circuitry in the bulb.

A rat model of human T lymphocyte virus type I (HTLV-I) infection. 1. Humoral antibody response, provirus integration, and HTLV-I-associated myelopathy/tropical spastic paraparesis-like myelopathy in seronegative HTLV-I carrier rats

Human T lymphocyte virus type I (HTLV-I) can be transmitted into several inbred strains of newborn and adult rats by inoculating newly established HTLV-I-immortalized rat T cell lines or the human T cell line MT-2. The transmission efficiency exceeds 80%, regardless of strain differences or the age at transmission. The production of anti-HTLV-I antibodies significantly differs among the strains and depends on the age at the time of transmission. Rats neonatally inoculated with HTLV-I-positive rat or human cells generally become seronegative HTLV-I carriers throughout their lives, whereas adult rats inoculated with HTLV-I-positive cells at 16 wk of age become seropositive HTLV-I carriers. The HTLV-I provirus genome is present in almost all organs, regardless of whether the carriers are seronegative or seropositive. According to antibody titers to HTLV-I, there are three groups of inbred rat strains: ACI, F344, and SDJ (high responders); WKA, BUF, and LEJ (intermediate responders); and LEW (low responder). Three of three 16-mo-old seronegative HTLV-I carrier rats of the WKA strain developed spastic paraparesis of the hind legs. Neuropathological examinations revealed that the lesions were confined primarily to the lateral and anterior funiculi of the spinal cord. Both myelin and axons were extensively damaged in a symmetrical fashion, and infiltration with massive foamy macrophages was evident. The most severe lesions were at levels of the thoracic cord and continued from the cervical to the lumbar area. These histopathological features as well as clinical symptoms largely parallel findings in humans with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). These HTLV-I carrier rats, in particular the WKA rats described above, can serve as a useful animal model for investigating virus-host interactions in the etiopathogenesis of HTLV-I-related immunological diseases, particularly HAM/TSP.

Synthesis and crystal structure of optically active 2-[benzyl(phenyl)amino]ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2,6-dim ethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate (NZ-105)

(S)-2-[Benzyl(phenyl)amino]ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate ((S)-NZ-105) and R isomer were synthesized through the fractional crystallization of (S)-2-Methoxy-2-phenylethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate. Calcium antagonism activity was found to reside in the S isomer from single crystal X-ray diffraction analysis.

Synthesis of 1,4-dihydropyridine-5-phosphonates and their calcium-antagonistic and antihypertensive activities: novel calcium-antagonist 2-[benzyl(phenyl)amino]ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2,6-dim ethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate hydrochloride ethanol (NZ-105) and its crystal structure

The effect of the 3-carboxylic-ester variation in 2,2-dimethyltrimethylene 3-alkoxycarbonyl-4-aryl-1,4-dihydro-2,6-dimethyl-5-pyridinephosphonat es (1) was investigated with relation to the calcium-antagonistic and antihypertensive activities: the analogs containing the alkyl groups of not more than 12 carbons and an amino functionality in the carboxylic-ester moiety were synthesized to be examined for biological activities. Among them, 2-[benzyl(phenyl)amino]-ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridine-carboxylate hydrochloride ethanol (NZ-105) showed particularly beneficial activities and was selected for further pharmacological studies and clinical development. Some aspects of the structure-activity relationships and solid-state structure of NZ-105 by X-ray crystallographic analysis were described.

Synthesis and biological activities of optical isomers of 2-(4-diphenylmethyl-1-piperazinyl)ethyl 5-(4,6-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2,6-dim ethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate dihydrochloride (NIP-101)

Six optical isomers of 2-(4-diphenylmethyl-1-piperazinyl)ethyl 5-(4,6-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate dihydrochloride (NIP-101, 1.2HCl.2H2O), a potent calcium antagonist, were successfully prepared by using optically active (2R,4R)-(-)- and (2S,4S)-(+)-2,4-pentanediols, and cis-2,4-pentanediol and optically active (S)-(+)-2-methoxy-2-phenylethanol. Their proton nuclear magnetic resonance investigations demonstrate that the 1,3,2-dioxaphosphorinane group is conformationally constrained around the C-P bond. Calcium-antagonistic and hypotensive activities of the optical isomers were examined and found to depend mainly on the absolute configuration at a stereogenic center in the 1,4-dihydropyridine ring rather than the configuration of the 1,3,2-dioxaphosphorinane moiety.