Redifferentiation of cancer cells: bestatin, estradiol, and prostaglandin D2

The induction of redifferentiation of cancer cells was studied. This was achievable with bestatin, especially in combination with sex hormones or prostaglandin D2, in murine undifferentiated mammary adenocarcinoma cells in vitro. Prostaglandin D2 also exerted a similar redifferentiating effect on M1 murine leukemia cells and a consecutive bestatin-hormone regimen was effective in endocrine tumors in man. Cancer redifferentiation may one day be developed into a clinical technique.

Hyperalgesic action in rats of intracerebroventricularly administered arachidonic acid, PG E2 and PG F2 alpha: effects of analgesic drugs on hyperalgesia

Hyperalgesic actions in rats of intracerebroventricularly (i.c.v.) administered arachidonic acid, prostaglandin (PG) E2 and PG F2 alpha were studied. For the analgesic assay, vocalization induced by repetitive electrical stimulation was employed. Administered i.c.v., arachidonic acid (0.1-30 micrograms/rat), PG E2 (0.001-0.3 micrograms/rat) and PG F2 alpha (0.01-3 micrograms/rat) potentiated the vocalization, in a dose-dependent manner. The maximal potentiating doses of arachidonic acid, PG E2 and PG F2 alpha were 10 micrograms/rat, 0.1 microgram/rat and 1 microgram/rat, respectively. Indomethacin and diclofenac produced much more potent analgesic effects in arachidonic acid-induced hyperalgesic rats than in normal rats and in PG E2- and PG F2 alpha-induced hyperalgesic rats, but aminopyrine, acetaminophen and morphine produced the same analgesic effect in both hyperalgesic and normal rats. Linoleic acid, linolenic acid and gamma-linolenic acid also induced a weak hyperalgesia, whereas indomethacin (4 mg/kg) failed to attenuate the vocalization in these unsaturated fatty acids-induced hyperalgesic rats. These findings indicate that the hyperalgesic actions of arachidonic acid and its metabolites are related to mediation or modulation of the central pain pathways, and the pain-relieving properties of acidic nonsteroidal antiinflammatory drugs (NSAIDs) may be, at least in part, involved in central site.

Histological evidence for rescue of radiation dermatitis in an ultraviolet model system

Rescue of acute radiation dermatitis has already been shown feasible with cytochrome c(Sci. Rep. Res. Inst. Tohoku Univ.-C 29: 1, 1982). Interest in the probable reduction of inflammatory sequelae led to histological studies in an ultraviolet model system in the rabbit. The relative dermal thickness in the field of ultraviolet irradiation was 1.70 +/- 0.30 (5) in the untreated control and 1.31 +/- 0.07 (5) in the cytochrome c group respectively (p less than 0.05). Usefulness of the principle cannot be overemphasized in the strategies of radiotherapy, and in the treatment and/or prevention of actinic radiation dermatitis.

Effects of ethanol and phenobarbital administration on the metabolism and toxicity of benzene

Effects of ethanol- and phenobarbital(PB)-treatment on the metabolism of benzene in vitro and in vivo, and on the benzene-induced hemotoxicity, were investigated. Ethanol consumption markedly enhanced in vitro metabolism of both benzene and phenol in rat liver, whereas PB-treatment, which enhanced the metabolism of phenol to some degree (about one-third of ethanol-induced enhancement), did not affect the metabolism of benzene. In a single exposure experiment with rats, ethanol increased benzene metabolism in vivo as evidenced by accelerated disappearance of benzene from the blood as well as by elevated urinary excretion of phenol, whereas PB produced little or no significant influence on the metabolism. In a 3-week exposure experiment, ethanol administration accelerated benzene disappearance from the blood in agreement with the single exposure experiment, but it tended to decrease urinary phenol excretion with repetition of exposure, probably due to concomitant stimulation of subsequent phenol metabolism by ethanol. Again, PB-treatment produced only a negligible effect on the metabolism of benzene. Ethanol consumption aggravated benzene-induced hemopoietic disorder as evidenced by a marked decrease in the peripheral white blood cell number. PB produced a protective effect on the toxicity. It is concluded that ethanol potentiates benzene toxicity by accelerating (1) hydroxylation of benzene, a rate-limiting step of benzene metabolism and (2) transformation of phenol into highly toxic metabolites.

Contralateral circling behavior induced by intranigral microinjections of taurine and GABA in rats

Circling behavior induced by unilateral microinjections of taurine and gamma-aminobutyric acid (GABA) into the substantia nigra zona reticulata (SNR) was studied in rats. Both taurine (10-100 micrograms/rat) and GABA (30-300 micrograms/rat) induced the contralateral circling behavior in a dose-dependent manner when they were microinjected into the SNR. Neither compound induced ipsilateral circling. An ipsilateral injection of 6-hydroxydopamine (6-OHDA) into the nucleus caudatus putamen (CPU) caused a reduction of the dopamine (DA) content in the injected side and decreased the circling behavior induced by taurine but not GABA. Electrolesion of the ipsilateral nucleus ventromedialis thalami (VM) decreased both taurine- and GABA-induced circling. In contrast, only GABA-induced circling was reduced by the electrolesion of the ipsilateral nucleus parafascicularis thalami (PF). Electrolesion of the ipsilateral nucleus accumbens (ACB) did not modify the circling behavior induced by GABA, but did decrease the circling induced by taurine. Electrolesion of the ipsilateral globus pallidus (GP) or nucleus entopeduncularis (EP) did not attenuate the circling behavior induced by either taurine or GABA. These results suggest that taurine-induced circling behavior may be mediated by the nigrostriatal-nigrothalamic system, and the ACB. In contrast, the nigrothalamic system may play an important role in GABA-induced circling behavior.

Effects on the caudate spindle in rats of taurine and gamma-aminobutyric acid (GABA) microinjected into the substantia nigra: involvement of the dopaminergic system

Spindle bursts (caudate spindle) were recorded from the frontal cortex in rats. The bilateral intranigral microinjection of taurine suppressed the caudate spindle, whereas the same dose of gamma-aminobutyric acid (GABA) did not suppress the caudate spindle. These results indicate that suppression of the caudate spindle induced by taurine may relate to activation of the nigrostriatal dopaminergic neurons.

Effects on the caudate spindle in rats of dopamine microinjected into the caudate nucleus

We examined the caudate spindle in control and pargyline-pretreated rats following bilateral application of 3 doses (15, 50 and 150 micrograms/site) of dopamine (DA) into the caudate nucleus. The highest dose of DA (150 micrograms) suppressed the spindle, whereas lower doses (15, 50 micrograms) enhanced the spindle in control rats. Haloperidol given into the bilateral caudate nucleus increased the spindle in control rats. In pargyline-pretreated rats, 50 and 150 micrograms DA caused marked suppression, but 15 micrograms DA caused enhancement. These findings indicate that the DA system may mediate the development of the caudate spindle. Suppression of the caudate spindle induced by intracaudate DA injection may be due to stimulation of postsynaptic DA receptors and enhancement mediated by DA autoreceptors on the DA nerve terminals in the caudate nucleus with a subsequent inhibition of DA neurotransmission.

Pharmacological studies of furo [3,2-b]indole derivatives. II. Analgesic effect of FI-302, N-(3-piperidinopropyl)-4-methyl-6-trifluoromethyl-furo[3,2-b]ind ole-2-carboxamide, in experimental animals

FI-302, N-(3-piperidinopropyl)-4-methyl-6-trifluoromethyl-furo[3,2-b]indol e-2-carboxamide, is a new non-steroidal anti-inflammatory compound. The analgesic effect of FI-302 was investigated in comparison with those of non-steroidal anti-inflammatory drugs (NSAIDs). In the tail pressure, hot plate and D'Amour and Smith methods, FI-302 showed a potent analgesic effect, its efficacy being about 2 to 7 times greater than those of aminopyrine, mepirizole and tiaramide. On the other hand, in these methods, aspirin, ibuprofen and phenylbutazone had little or no effect. FI-302 showed a potent inhibitory effect on the vocalization response produced by electrical stimulation. Moreover, the analgesic effect of FI-302 after intracerebroventricular injection was about 58 to 278 times more potent than those of tiaramide and ibuprofen, and about 1/6 that of morphine. However, the analgesic effect of FI-302 was not antagonized by levallorphan. From these results, it appears that FI-302 has potent analgesic effects which may be produced by both peripheral and central mechanisms, but it is a non-narcotic compound. Consequently, FI-302 should be suitably applicable for clinical purposes.

[Clinical analysis of vitreous hemorrhage combined with ruptured aneurysm]

Eight cases of vitreous hemorrhage with ruptured intracranial aneurysm (Terson's syndrome) were experienced in our clinic from April, 1978 to April, 1983. They consisted of five males and three famales between 45 and 69 years old. All cases had unconscious attacks and three of them experienced repeated episodes of subarachnoid hemorrhage within 24 hours. CT scan, performed 24 hours within the attack, revealed remarkable high density areas at prepontine and suprasellar cisterns, interhemispheric and sylvian fissures. Ruptured aneurysms, confirmed by cerebral angiography and operative findings, were three anterior communicating artery aneurysms, three internal cerebral artery aneurysms, one middle cerebral artery aneurysm and one anterior cerebral artery aneurysm. We performed radical operation for the ruptured aneurysm, six cases at acute atage, one at 11 days and one at 18 days after the attack. Postoperative courses were all good. Five cases had bilateral vitreous hemorrhages and three had unilateral ones. At first they were treated conservatively. Visual acuity of six cases, 13 eyes improved gradually, but three cases, four eyes did not improve after four or five months after the attack. So we let ophthalmologist to perform vitrectomy, which showed effective results. Vitreous hemorrhage following a ruptured intracranial aneurysm is not a so rare complication than has been assumed and also its prognosis is not so poor. In most cases vitreous hemorrhage following a ruptured intracranial aneurysm should be treated conservatively, but in selected cases effective results would be given by vitrectomy.

The site of action of morphine and indomethacin differs with electrical stimulation of cutaneous or tibial nerves in normal and adjuvant arthritic rats

Evoked potentials were recorded from the ventrobasal (VB) thalamus in normal and adjuvant arthritic rats anaesthetized with urethane (1200 mg/kg, i.p.). Effects of morphine and indomethacin on the evoked potentials elicited by transcutaneous electrical stimulation (TES) or tibial nerve electrical stimulation (TNES) were investigated. Morphine (1-3 mg/kg, i.v.) significantly depressed the potentials evoked by TES an TNES, in both groups. The magnitudes of the depressant effect of morphine were roughly equivalent, in each experiment. In normal rats, indomethacin (3-10 mg/kg, i.v.) significantly depressed the evoked potentials elicited by TES, but did not depress the evoked potentials elicited by TNES. In adjuvant arthritic rats, indomethacin (1-10 mg/kg, i.v.) depressed the evoked potentials elicited by TES and also, be it less readily, those elicited by TNES effects were more readily produced by TES than by TNES. These results suggest that the site of action of indomethacin differs in normal and adjuvant arthritic rats. The central antinociceptive action of indomethacin is clearly detectable in the presence of chronic inflammation. The antinociceptive action of morphine may reside in the neo-spinothalamic projection system, in both groups of rats.

Pharmacological studies of furo [3,2-b] indole derivatives. I. Analgesic, anti-pyretic and anti-inflammatory effects of FI-302, N-(3-piperidinopropyl)-4-methyl-6-trifluoromethyl-furo [3,2-b]indole-2-carboxamide, in experimental animals

The analgesic, anti-pyretic and anti-inflammatory effects of FI-302, N-(3-piperidinopropyl)-4-methyl-6-trifluoromethyl-furo [3,2-b]indole-2-carboxamide, a newly synthesized tricyclic compound, were investigated in comparison with those of nonsteroidal anti-inflammatory drugs (NSAIDs). FI-302 showed potent analgesic and antipyretic effects in the various models used. FI-302 showed an inhibitory effect on acute inflammatory response such as carrageenin-induced edema, but did not show any effect on chronic inflammatory response such as cotton pellet granuloma. These effects of FI-302 were about 2 to 7 times more potent than those of non-acidic NSAIDs such as mepirizole and tiaramide. Moreover, FI-302 had little or no ulcerogenic activity. From these results, it is conceivable that the spectrum of FI-302's activities is similar to those of non-acidic NSAIDs such as mepirizole and tiaramide. These results suggest that FI-302 is a new non-ulcerogenic anti-inflammatory compound, and should be suitably applicable for clinical purposes.

[Radiochemotherapy of head and neck cancers: dose reduction through the combination of cisplatin, bleomycin and tegafur]

Twenty-four cases of squamous cell carcinomas of the larynx and maxillary sinus were irradiated with or without cisplatin during a period from April 1973 through March 1984. Both bleomycin in oil and tegafur were administered irrespective of cisplatin. Therapeutic effectiveness was critically evaluated by means of serial biopsy and/or surgery. Radiotherapy alone could not bring about negative conversion of the biopsies, but ultimate negative conversion was observed in 18 out of the 24 cases when chemotherapeutics were appropriately combined. The five positives underwent surgery. In the cases of maxillary cancer, mixed infections appeared to interfere with the curative effectiveness of the radiochemotherapy. A resulting dosage reduction of 15Gy was observed in radiotherapy for negative conversion and one of 10mg for bleomycin as a result of incorporation of cisplatin.

Effects of morphine and indomethacin on evoked neuronal responses of ventrobasal thalamic neurones: site of action of analgesic drugs in non-adjuvant arthritic rats

Single neuronal activity was recorded extracellularly in the ventrobasal (VB) nucleus of the thalamus in non-adjuvant arthritic rats under urethane (1200 mg/kg, i.p.) anesthesia. The effects of morphine and indomethacin on the evoked responses elicited by noxious stimuli such as transcutaneous electrical stimulation (TES) or tibial nerve electrical stimulation (TNES), or non-noxious stimulation such as repetitive brushing were examined. Intravenous administered morphine (0.1, 0.3 and 1 mg/kg) depressed the evoked responses elicited by either TES or TNES without affecting any background activities. In contrast, intravenous administered indomethacin (1, 3 and 10 mg/kg) depressed the evoked responses induced by TES, but failed to depress the evoked responses induced by TNES. At doses of 3 and 10 mg/kg, indomethacin slightly depressed the background activities of the nociceptive neurones. Depressant effects of morphine were restored by intravenous naloxone (0.5 mg/kg) administration, but not observed in case of indomethacin. The evoked responses induced by non-noxious stimulation failed to depress either indomethacin or morphine administration. These results suggest that the site of action of indomethacin in non-adjuvant arthritic rats is mainly in the periphery. In contrast, morphine produced an antinociceptic action due to the central mechanism.

Possible involvement of non-steroidal anti-inflammatory drugs in vagal-mediated gastric acid secretion in rats

Effects of several non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin (ASA), indomethacin (IM), flurbiprofen (FP), ibuprofen (IP), phenylbutazone (PBZ) and flufenamic acid (FA) were studied on the gastric ulceration and gastric acid secretion induced by restraint and water-immersion stress (RWIS) or various secretagogues in rats. These drugs significantly increased ulcer formation. IM (1, 3 and 10 mg/kg, s.c.) reduced gastric mucosal prostaglandin (PG) content dose-dependently. There was an appreciable correlation between this decrease in the PG content of gastric tissue and associated ulceration. The gastric acid secretion induced by the peripheral secretagogues, methacholine, gastrin and histamine, was not significantly influenced by IM pretreatment. In contrast, the gastric acid secretion induced by the vagal mediated secretagogues, insulin, 2-deoxy-D-glucose (2-D-G) and RWIS, was markedly increased by IM pretreatment. These effects were not observed in vagotomized rats. By intracerebroventricular (i.c.v.) injection of IM, no influence was observed on the gastric acid secretion and ulcer formation induced by 2-D-G or RWIS. These results suggest that acidic NSAIDs potentiate the gastric acid output induced by stimulation of vagus nerve activity, and prostaglandins (PGs) may influence gastric acid output by regulating vagus nerve activity.

Effects of morphine and indomethacin on evoked neuronal responses of ventrobasal thalamic neurones: site of action of analgesic drugs in adjuvant arthritic rats

A single neuronal activity was recorded extracellularly in the ventrobasal (VB) nucleus of the thalamus in adjuvant arthritic rats under urethane anesthesia (1200 mg/kg, i.p.). The effects of morphine and indomethacin on the evoked responses elicited by noxious stimuli (transcutaneous electrical stimulation and tibial nerve electrical stimulation) and/or non-noxious stimuli were investigated. Intravenous administration of morphine and indomethacin depressed the evoked responses elicited by either transcutaneous electrical stimulation or tibial nerve electrical stimulation without affecting any background activities. By contrast, the responses of all neurones investigated responding to non-noxious stimuli were never depressed by the intravenous administration of morphine and indomethacin. Morphine showed the same depressant effects on the evoked responses activated by both noxious stimuli, but the depressant effects due to indomethacin on the evoked discharges were more sensitively produced by transcutaneous electrical stimulation than tibial nerve electrical stimulation. Depressant effects of morphine were restored by intravenous naloxone administration, but not observed in case of indomethacin. These results suggest that an analgesic mechanism of morphine and indomethacin may reside in the neo-spinothalamic projection system of adjuvant arthritic rats and that the site of action of indomethacin may also reside in a peripheral site. However, the mode of the central action of indomethacin was different from that of morphine.

A case report of benign recurrent intrahepatic cholestasis

A case of benign recurrent intrahepatic cholestasis was reported. A man had first experienced jaundice at the age of twenty-five, and suffered three subsequent attacks over the next five years. These attacks were characterized by prodromal severe pruritus. During the icteric phase, serum levels of total bile acids increased, most being conjugates of primary bile acids. Electron microscopy revealed that the bile canaliculi were filled with an increased volume of granular substances. Some bile canaliculi fused together resulting in the formation of abnormally elongated channels which abutted on the Disse space. These observations suggest bile regurgitation through the channel of altered canaliculi. In convalescence, these bile canaliculi disappeared. Every attack was followed by complete recovery of liver structure and function.

Exfoliation as a mode of cancer elimination in rectal carcinoma

A histopathological survey of surgical materials from 143 patients with rectal carcinoma subjected to chemotherapy and low-dose radiotherapy with tegafur and bleomycin was carried out. The chemotherapy combined with radiotherapy brought about better results than chemotherapy alone. In 4 of the 58 patients treated with radiochemotherapy, no cancer cells could be found in surgical specimens. Exfoliation into the rectal lumen of cohorts of cancer cells may occur in some cases of rectal carcinoma thus treated, resulting in cancer cell elimination.

Consecutive bestatin-hormone regimen induces redifferentiation of cancer cells in vitro

When undifferentiated murine mammary adenocarcinoma cells were consecutively exposed to bestatin and estradiol or testosterone in vitro, morphological signs of redifferentiation of the cells were observed along with cellular enlargement and subsequent cell loss. These observations suggest that similar treatments can be applied clinically to cancers of the breast and prostate.

[Effect of various types of analgesic drugs on an experimental model of chronic inflammatory pain in mice]

We attempted to develop an experimental model of chronic inflammatory pain in mice. The mice were injected intradermally at the base of the tail with various kinds of irritants (yeast, carrageenin, mustard and adjuvant). The pain threshold was measured by the pressure method every 60 min for 5 hr and once a day at the same time throughout the experimental period. The group of 10% yeast-injected mice exhibited the most intensive hyperalgesia. The analgesic effect of various types of analgesic drugs were studied, comparing the effects in normal mice and various kinds of irritants-induced hyperalgesia mice. It was demonstrated by observing ED50 values that nonsteroidal antiinflammatory drugs (NSAIDs), narcotic analgesic drugs and agonist/antagonist type of analgesic drugs were effective, but CNS-acting drugs were ineffective in yeast hyperalgesia mice. In comparison with yeast hyperalgesia mice, larger doses of analgesic drugs were required in normal mice and other irritants-treated mice. Especially, acidic NSAIDs were more effective in yeast hyperalgesia mice than normal mice. It was suggested that acidic NSAIDs specifically inhibit inflammatory pain. Moreover, yeast hyperalgesia mice are useful for the quantitative measurement of analgesic drugs.

The mode of action of analgesic drugs in adjuvant arthritic rats as an experimental model of chronic inflammatory pain: possible central analgesic action of acidic nonsteroidal antiinflammatory drugs

The analgesic activities of intracerebroventricular (icv) administrations of some analgesic drugs, morphine, indomethacin, diclofenac, aminopyrine and acetaminophen, were studied in comparison with those of systemic administrations in normal rats and adjuvant arthritic rats. A method for the measurement of analgesic potency in normal rats and adjuvant arthritic rats were developed using the vocalization response as an indicator of pain resulting from electrical stimulation. The systemic and/or icv administered indomethacin and diclofenac produced much more potent analgesic action in adjuvant arthritic rats than in normal rats. Morphine, aminopyrine and acetaminophen given by the two routes showed roughly the same analgesic effect in both types of rats. Simultaneous systemic and icv administrations of indomethacin and/or diclofenac showed an additive effect in normal rats, but showed a synergistic effect rather than a simple additive effect in adjuvant arthritic rats. Those of morphine, aminopyrine and acetaminophen showed only additive effects in both types, except for that of aminopyrine in normal rats. Moreover, the brain and serum levels of non-metabolized indomethacin and aminopyrine were measured after the normal and adjuvant arthritic rats were systemically given these drugs. In adjuvant arthritic rats, the icv effective dose of indomethacin was the same as the brain level of non-metabolized indomethacin after the systemic administration. The effective dose of indomethacin administered icv in the normal rats was 17 times higher than the brain level of non-metabolized indomethacin administered systemically. The icv effective dose of aminopyrine was 4-4.5 times higher than the level of the brain concentration of non-metabolized drug in both types of rats.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparative studies on 99mTc-pyrophosphate and 85Sr-chloride for skeletal imaging]

In order to know the potential merits of 99mTc-pyrophosphate (99mTc-PYP) skeletal imaging, a comparative study was carried out by administering to the rabbit 85Sr-chloride (85Sr), classical bone-seeking agent, and 99mTc-PY simultaneously. Radioisotopic distribution was investigated as regards their deposition in the pelvic bones, and sharpness of the skeletal scintigrams, too. Both agents were remarkably affinitive to the skeletal system and there were remarkably differences in their temporal deposition pattern. Marked deposition was observed of either agent in the metaphyses. With 99mTc-PYP, the vertebral and costal systems were delineated symmetrically and each vertebral body was distinctly depicted as such 99mTc-PYP many possess the following merits over 85Sr; (1) owing to its physical properties, sufficiently large radioactivity of 99mTc-can be administered; (2) body burden of radiation absorption is reduced; (3) skeletal scintigrams of high quality are obtainable in a short period of time.

[The analgesic and antipyretic effects of a non-steroidal anti-inflammatory drug, oxaprozin, in experimental animals]

The analgesic and antipyretic effects of oxaprozin were investigated in comparison with those of indomethacin, ibuprofen, phenylbutazone and aspirin. On the various writhing tests in mice, the analgesic effect of oxaprozin was about 2 to 9 times more potent than those of ibuprofen, phenylbutazone and aspirin. On the other hand, the analgesic and antipyretic effects of oxaprozin in rats were roughly equivalent to those of aspirin, but less effective than those of the other drugs tested. On the urate synovitis test in dogs, only oxaprozin showed a prophylactic effect. Therefore, The effect of oxaprozin in mice and dogs was more potent than ibuprofen, phenylbutazone and aspirin. The metabolic rate of oxaprozin in rats is 3.5 and 7.2 times more rapid than in mice and dogs, respectively, and its blood level in rats is low. Moreover, the biological half-life of oxaprozin is 39 to 43 hr and 49 to 69 hr in dogs and humans, respectively. From these results, it is suggested that oxaprozin is more potent than ibuprofen, phenylbutazone and aspirin, and in clinical use, it is a long acting anti-inflammatory drug.

Gallium induces reduction of negative charge of the cell membrane and redifferentiation of cancer cells

In order to obtain an insight into the mechanism of experimentally induced redifferentiation of cancer cells, changes in negative charge of the cell membrane were examined by cytopherometry following in vitro exposure of the cancer cells to non-radioactive gallium. Reduction of the negative charge was observed at 24 hr and later. The gallium ions must have neutralized the negative charge of the cancer cell membrane to the normal range. This event may contribute in some way to cancer cell redifferentiation.

Decrease in saturation density of mammalian carcinoma cell culture during exposure to bestatin, a clinically applicable agent

Bestatin, one of the small molecular products of Streptomyces olivoreticuli , and a potential immunostimulator, was shown to decrease the saturation density of murine carcinoma cell culture. The finding may indicate a possibility of direct action of bestatin upon cancer cells presumably resulting in cancer cell redifferention .

Inhibition of electrically-induced vocalization in adjuvant arthritic rats as a novel method for evaluating analgesic drugs

A new method for the evaluation of analgesic drugs in normal rats and in rats with hyperalgesia induced by adjuvant was developed using the vocalization response as an indicator of pain due to electrical shock. It was demonstrated that at ED50 doses, nonsteroidal anti-inflammatory drugs (NSAIDs), narcotic analgesic drugs and narcotic agonist/antagonist type analgesic drugs were effective, but pure narcotic antagonist drugs. CNS-acting drugs and anti-inflammatory steroid were ineffective. Acidic NSAIDs, except aspirin, were more effective in adjuvant arthritic rats than normals but other analgesic drugs had roughly the same effect in both. It was suggested that the acidic NSAIDs specifically inhibit inflammatory pain. Moreover, the vocalization response under adjuvant treatment is useful for the quantitative measurement of analgesics.

Crystalline retinopathy

A 52-year-old Japanese woman had retinal crystalline deposits with atrophy of the pigment epithelium and choriocapillaris and pigment clumps in the periphery. The patient did not have corneal crystals. The crystals were seen biomicroscopically in all layers of the retina and on the retinal vessels. The diagnosis of crystalline retinopathy was made. The progressive nature of the disease was confirmed, based on a 9-year follow-up. The authors reviewed this condition in the Japanese literature and believe that crystalline retinopathy may not be as rare in the Orient as previously thought.

[Combined radiotherapy and chemotherapy for the treatment of esophageal cancer]

Eight patients with esophageal cancer were treated by a new treatment schedule consisting of low dose irradiation, crescendo cisplatin and bleomycin polyacrylate pasta. As monitored endoscopically, therapeutic responses were satisfactory: seven out of 8 patients have survived for a range of 3 to 20 months and still active at work or cancer-free. However, one patient suffered from a second malignancy of adenocarcinoma of the upper esophagus different from the initial squamous cell carcinoma at the lower esophagus which had successfully been treated 3 months before. The present therapeutic design aims at treatment of lymphatic spreads in the adjacent structures as well as the original tumor in the esophagus and submucosal invasions. It is basically a consecutive, multimodal integration of selective concentration of therapeutic effects (extensive radiotherapy, topical application of bleomycin polyacrylate pasta, lymphatic chasing with colloidal bleomycin, and spatial concentration of cisplatin as the result of radiation-induced inflammation), perpetuation of the repairable DNA damage, and biological amplifications (protection against esophageal perforation with polyacrylate coating, and specific cancer cell recruitment). Application of the present therapeutic design is being expanded to the treatment of cancer of other specific sites such as the head and neck tumors and rectal cancer with undeniable prospects.

Synthesis and 5-lipoxygenase inhibitory activities of eicosanoid compounds

Ten eicosanoid compounds (3, 6, 9, 11, 12, 15, 18, 21, 23, and 25), methyl (6E,8Z,11Z,14Z)-5-hydroxy-6,8,11,14-eicosatetraenoate (5-HETE, 10), leukotriene A4 (26), and (5S,6E,8E,10E,12RS,14E)-5,12-dihydroxy-6,8,10,14-eicosatetraenoic acid (5,12-diHETE, 27) were prepared and their inhibitory activities against the 5-lipoxygenase from guinea pig polymorphonuclear leukocytes (PMNL) were tested. 5,6-Methanoleukotriene A4 (18) was especially a potent and specific inhibitor of the 5-lipoxygenase without inhibiting the cyclooxygenase and the 12-lipoxygenase. Leukotriene A4, 5-HETE, and 5,12-diHETE also have inhibitory activities against the 5-lipoxygenase at micromolar concentrations, which can regulate the formation of slow-reacting substance of anaphylaxis intracellulary.