[Estrogen production in epithelial tumors of the ovary--localization of estrogen-synthesizing cells]

The origin of the elevated serum estrogen in postmenopausal patients with common epithelial tumors of the ovary was investigated by means of endocrinological, histochemical, immune histochemical and autoradiographic techniques. Estrone and estradiol and their precursors were quantitatively extracted from the tumor tissue homogenate, and the results indicated that the estrogen-producing pathway was not uniform among the tumors. On the tissue section Sudan-IV staining showed positive in the stromal area in the form of fine granules or droplets. The immune peroxidase method revealed that the Sudan staining-positive substance included estrogen and its precursors. Estrogen was also detected in the epithelium, but it seemed to be present in the epithelial (tumor) cells as an estrogen-estrogen receptor complex. Cholesterol staining was focally positive in the subepithelial stromal area and incorporation of 3H-cholesterol into the stromal cells was observed by microautoradiography. These findings indicated that steroid synthesis from cholesterol to estrogen appeared in the stroma of the tumor and high serum concentrations of estrogen in the patient were the result of accelerated estrogen-synthesis in the ovarian tumor.

Behavioral analysis of zopiclone on the basis of their discriminative stimulus properties in the rat

Zopiclone is a new cyclopyrrolone derivative which exerts pharmacological activities similar to those of benzodiazepines in behavioral and biochemical studies. In order to clarify the discriminative stimulus properties of zopiclone, 8 rats were trained to discriminate the interoceptive stimulus induced by zopiclone (3.2 mg/kg, i.p.) from those of saline. Following discrimination acquisition, administration of zopiclone resulted in drug-appropriate responding with an ED50 of 1.3 (1.0-1.8) mg/kg. The zopiclone discriminative stimulus generalized to the benzodiazepines diazepam (1.8 mg/kg), nitrazepam (10 mg/kg) and alprazolam (10 mg/kg). A non-benzodiazepine, suriclone, at 3.2 mg/kg, generalized to the zopiclone stimulus in 5 out of 7 rats, but meprobamate, hydroxyzine, tracazolate and muscimol did not. The benzodiazepine antagonist Ro 15-1788 (1 mg/kg) completely blocked zopiclone stimulus. In contrast, however, bicuculline and pentetrazol failed to antagonize it. The serotonin antagonist cinanserin and ritanserin neither generalized to the zopiclone stimulus nor did they exhibit antagonism. These results suggest that the zopiclone discriminative stimulus is mediated by binding to benzodiazepine receptors and appears not to be related to GABAergic or serotonergic system.

Conflict behavior and dynamics of monoamines of various brain nuclei in rats

The present study was an attempt to clarify the role of noradrenaline (NA) and of the 5-hydroxytryptamine (5-HT) system in various nuclei in brain, as a component of a proposed neural circuit in the mediation of conflict behavior and the anticonflict action of anxiolytics. The authors investigated changes in the concentrations of NA, 3-methoxy-4-hydroxyphenylethyleneglycol, 5-HT and 5-hydroxyindoleacetic acid in discrete regions of the brain in rats, in correlation with conflict behavior and also the effects of diazepam and suriclone. Noradrenergic neural activity diminished with a conflict situation, in the frontal cortex, central amygdala, mammillary body and dorsal hippocampus. 5-Hydroxytryptaminergic neural activity increased with a conflict situation in the frontal cortex, central amygdala, basolateral amygdala and medial septum. These changes in the frontal cortex, central amygdala, mammillary body and dorsal hippocampus were not observed when diazepam 20 mg/kg (p.o.) and suriclone 40 mg/kg (p.o.) produced anticonflict action. Suriclone normalized the increased 5-HT-ergic activity in the medial septum. The suppression of NA-ergic and the activation of 5-HT-ergic (except for the mammillary body) neural activity in the frontal cortex, central amygdala, mammillary body and dorsal hippocampus seemed to be linked to the mediation of conflict behavior. The facilitatory and inhibitory action on NA and 5-HT (except for the mammillary body) neurons, respectively, in these regions of the brain, may be involved in mechanisms underlying the anticonflict action of anxiolytics (diazepam or suriclone).

Inhibition of mouse-killing behavior by S-adenosyl-L-methionine in midbrain raphe-lesioned and olfactory-bulbectomized rats

The effect of S-adenosyl-L-methionine (SAM), a methyl donor, on mouse-killing behavior in rats with lesions of the midbrain raphe nuclei and in olfactory-bulbectomized rats was investigated. Systemic administration of SAM at doses of 180 and 320 mg/kg IP caused a significant inhibition of both kinds of mouse-killing behavior. The inhibitory effects of SAM on both types of mouse-killing behavior were almost equipotent. Microinjection of SAM at 10-100 micrograms/rat into the lateral ventricle also inhibited mouse-killing behavior induced by raphe lesions in a dose-dependent manner. The ED50 value of SAM for this effect was 38.6 (18.4-81.4) micrograms/rat. It is concluded that SAM has inhibitory effects on mouse-killing behavior in both raphe-lesioned and olfactory-bulbectomized rats through a site of action in the central nervous system.

Fine structure of cartilage elastic system fibers, in particular those of the mandibular condyle

Light microscopy of the mandibular joint tissues from fetal mice show a distribution of fibrillar structures in the articular fibrous capsule covering the condylar head. Further SEM and TEM studies were conducted on autoclaved xiphoid and mandibular condylar processes of the fetuses for observation of the elastic system fibers in these cartilaginous tissues. SEM showed that non-collaginous fibers branched and united to form a complicated network in the cartilage. A fine structure study on diameter distribution of the fibers indicated elastogenesis in the differentiating cell layer and fiber maturation in the articular surfaces and calcification layer, thus suggesting a sequential development, growth, and degeneration of the cellular and fibrillar components in the cartilage, as well as bidirectional cell differentiation in the growing mandibular joint. A further TEM study on these autoclaved connective tissues showed the elastic system fibers in the network to be composed of fine microfibrils and amorphous elastin. The elastic fibers in the condylar cartilage were a loose network having many tortuous main and oblique elastic fibers, and coiling oxytalan fibers.

Neuroanatomical substrates regulating rat conflict behavior evidenced by brain lesioning

The present study was designed to clarify neural circuits involved in the mediation of behavioral suppression using the Vogel type conflict procedure in rats. Among the brain nuclei inclusive of neuroanatomical substrates of behavioral suppression, lesioning of the central amygdala, mammillary body or frontal cortex led to a significant increase in the punished drinking responses. Lesion of the septum also tended to increase these responses. These results show the key role of these brain areas in mediation of behavioral suppression such as conflict behavior.

[Human papilloma virus (HPV) antigens and DNA in dysplasia and carcinoma of the uterine cervix]

Routinely paraffin-embedded sections of dysplasia, carcinoma in situ (CIS) and invasive (squamous) carcinoma of the cervix were studied to determine the participation of human papilloma virus (HPV) in these tissues. Morphological observation (1,059 cases) revealed condylomatous changes to reach 54% in dysplasia, 25% in CIS and 25% in invasive carcinoma. Condylomatous changes were also found to be 25 to 40% in the non-cancerous epithelia adjacent to in situ or invasive carcinomas. The immuno-peroxidase-PAP-method using anti-HPV serum was applied to 98 selected sections in which condylomatous changes were morphologically observed. HPV antigens were found to reach 56% in dysplasia, 42% in CIS and 35% in invasive carcinoma, and this result suggested that the morphologically observed condylomatous changes did not always coincide with virus maturation in the infected cells. By means of the in situ hybridization technique, HPV type-6, -11, -16 and -18 DNAs were all detected in dysplasia sections, whereas HPV type-16 DNA was demonstrated distinctively at a high rate among in situ and invasive carcinomas.

[Behavioral pharmacological properties of the novel antidepressant paroxetine, a selective 5-HT uptake inhibitor]

The behavioral effects of paroxetine were investigated in mice and rats in comparison with imipramine and amitriptyline. 1) Locomotor activities were decreased by imipramine and amitriptyline but not by paroxetine in both animal species. 2) Paroxetine antagonized methamphetamine-induced hyperactivity in mice as did imipramine and amitriptyline. 3) Paroxetine showed a more potent antimuricidal effect in raphe-lesioned rats than imipramine and amitriptyline, and it also inhibited muricide in olfactory bulbectomized rats. 4) The immobility of rats in the forced swimming test was markedly decreased by imipramine and amitriptyline, but only slightly by paroxetine. 5) Like imipramine and amitriptyline, paroxetine potentiated the methamphetamine- or L-DOPA-induced stereotyped sniffing, and it inhibited oxotremorine-induced tremor. 6) Paroxetine antagonized reserpine-induced hypothermia, tetrabenazine-induced ptosis, and enhanced ether-induced anesthesia, all less potently than imipramine and amitriptyline. 7) The analgesic action of paroxetine was stronger than that of imipramine and amitriptyline. 8) Paroxetine did not antagonize maximal electroshock- or pentetrazol-induced convulsions and haloperidol- or THC-induced catalepsy in rats. In addition, paroxetine neither exerted muscle relaxation nor affected the shuttle-box type conditioned avoidance in rats. From these results, the behavioral effects of paroxetine, as compared with imipramine and amitriptyline, were characterized by its potent antimuricidal action in raphe-lesioned rats and its weak effect in the forced swimming test and by its less potent muscle relaxant, anticonvulsant, anticataleptic and anesthesia-potentiating actions.

Effect of S-adenosyl-L-methionine on impairment of working memory induced in rats by cerebral ischemia and scopolamine

A repeated acquisition procedure in a 3-panel runway apparatus was used to investigate the effects to S-adenosyl-L-methionine (SAM) on impairment of working memory produced either by cerebral ischemia or by scopolamine in rats. Cerebral ischemia (2-10 min) produced duration-dependent increases in the number of errors (pushes made on the two incorrect panels located at each choice point) and increased latency (time before the rat reached the goal box). The increase in errors induced by a 5 or 10 min period of ischemia decreased gradually in subsequent training sessions, returning to the control levels in 6 days. The increases in both errors and latency induced by 5 min of ischemia were significantly reduced by 100 and 180 mg/kg SAM administered i.p. immediately after blood recirculation and 1 h before a test conducted 24 h after ischemia. SAM at doses up to 180 mg/kg nevertheless failed to reduce the increases in errors and latency if they were induced by 0.56 mg/kg of scopolamine. These results suggest that SAM has a beneficial effect on memory that has been impaired by cerebral ischemia.

Effect of bilateral septal lesions on discrimination avoidance conditioning in rats

Studies were performed, using the two-way shuttle box method, on the acquisition of discrimination avoidance by rats with bilateral lesions of the septum (septal rats) in relation to changes in emotional behavior. Septal rats exhibited hyperreactivity immediately after the lesions were made: their startle, struggle and vocalization responses to stimuli were markedly increased. These hyperemotional responses, however, decreased and returned to the normal level 7 days after surgery. Initially, the septal rats showed elevated conditioned avoidance responses to both the CS+ and the CS-. In later stages, their responses to the CS+ showed progressive and gradual increase, accompanied by a decrease in responses to the CS-, until responses to both stimuli were only slightly elevated above the level of control rats. These results suggest that bilateral lesions of the septum do not affect discrimination ability itself. The impairment of discrimination avoidance during the initial stages may result from the transient impairment of the discrimination acquisition process.

Delta 9-tetrahydrocannabinol facilitates striatal dopaminergic transmission

We examined the effects of delta 9-tetrahydrocannabinol (THC) on striatal dopaminergic neurons in rats. THC inhibited the uptake of 3H-dopamine (DA) into striatal synaptosomes. THC facilitated the release of endogenous DA but not dihydroxyphenylacetic acid (DOPAC) from striatal slices. The concentration of DA in the dorsolateral striatum was reduced by THC. We propose that THC may stimulate nigrostriatal dopaminergic neurotransmission mainly by inhibiting uptake of DA and by facilitating release of DA.

Relative importance of the dopaminergic system in haloperidol-catalepsy and the anticataleptic effect of antidepressants and methamphetamine in rats

The mechanisms involved in haloperidol (HPD)-catalepsy in rat and the effect of antidepressants and methamphetamine (MA) were studied. HPD-catalepsy, as measured by high bar test, lasted for 6-8 min. MA, imipramine (IMP), nomifensine (NOM) and mianserin (MIAN) reduced the duration of catalepsy on IP injection. Electrolytic lesion of the caudate-putamen (CP) and nucleus accumbens (ACC) extensively reduced HPD-catalepsy. Microinjection of MA and NOM into ACC had a similar effect. In the medial amygdala and CP, only MA displayed anticataleptic activity. Zimelidine did not reduce the duration of catalepsy. These results suggest that dopaminergic systems play a key role in mediating HPD-catalepsy and the anticataleptic activity of MA and NOM.

Experience with the ultrasonic surgical aspirator in a cavernous hemangioma of the cavernous sinus

A patient with a cavernous hemangioma of the cavernous sinus was operated upon using the Cavitron Ultrasonic Surgical Aspirator (CUSA). Intracapsular subtotal removal of the tumor was accomplished efficiently with the CUSA. At the end of the procedure, however, the CUSA penetrated not only the capsule of the tumor, but also the wall of the internal carotid artery. Advantages and disadvantages of CUSA surgery for cavernous hemangiomas of the cavernous sinus are discussed.

Inhibitory effect of a selective kappa receptor agonist, U-50, 488H, on methamphetamine-elicited ipsilateral circling behavior in rats with unilateral nigral lesions

The present study was designed to investigate the effect of U-50, 488H, a highly selective kappa opioid agonist, on ipsilateral and contralateral circling behavior induced by methamphetamine and by apomorphine, respectively. U-50, 488H (3.2-10 mg/kg IP) by itself failed to induce either ipsilateral or contralateral circling in rats with unilateral nigral lesions produced by an injection of 6-hydroxydopamine. U-50, 488H produced a significant dose-dependent inhibition of methamphetamine (1.0 mg/kg SC)-elicited ipsilateral circling. However, it had no effect on contralateral circling induced by apomorphine (0.5 mg/kg SC). The present results indicate that U-50, 488H presynaptically inhibits the release of dopamine in the rat striatum.

Effect of isofloxythepin, a novel neuroleptic, on hippocampal stimulation-induced wet-dog shaking in the rat

(+/-)Isofloxythepin (0.32-3.2 mg/kg, i.p.) significantly inhibited in a dose-dependent manner wet-dog shaking (WDS) induced by electrical stimulation of the rat hippocampus. In addition, both optical isomers of isofloxythepin inhibited WDS, with the (-)-isomer being almost 3 times more potent than the (+)-isomer. Other neuroleptics such as haloperidol, chlorpromazine, zotepine and sulpiride also reduced significantly the number of WDS. The inhibitory potency of haloperidol was comparable to that of (+/-)isofloxythepin, which was approximately 3 times more potent than that of chlorpromazine or zotepine. Sulpiride suppressed significantly WDS only at the high dose of 100 mg/kg. None of the drugs affected hippocampal afterdischarge. Inhibition of WDS produced by (+/-) isofloxythepin or haloperidol was antagonized by pretreatment with a dopamine receptor agonist, lisuride. The present results indicate that isofloxythepin shares with other neuroleptics an inhibitory effect on WDS; dopaminergic blocking action appears to be important in the inhibition of WDS induced by hippocampal stimulation.

Effect of Z-103 on compound 48/80-induced gastric lesions in rats

Z-103 (a novel anti-ulcer agent), given p.o. at doses of 30 and 100 mg/kg, significantly prevented gastric lesions induced by compound 48/80 in rats. Z-103 inhibited the histamine release from rat peritoneal mast cells stimulated by compound 48/80 in a dose-dependent manner. Z-103 inhibited the increase in thiobarbituric acid (TBA) reactants induced by a single or repeated administration of compound 48/80 in the gastric mucosa. These observations suggested that the protective effect of Z-103 against compound 48/80-induced gastric lesions may be due to its stabilizing activity toward mast cells and/or an antioxidative effect on the gastric mucosa.

Effects of benzodiazepine and GABA antagonists on anticonflict effects of antianxiety drugs injected into the rat amygdala in a water-lick suppression test

In order to elucidate the role of the amygdala in rat conflict behavior in a water lick suppression test, we examined the effect of lesions of various nuclei of the amygdaloid complex on this behavior. An anticonflict effect was produced by a lesion of the anterior part of central and basolateral amygdala, and lesion to the posterior part of the central amygdala, but not by posterior of the basolateral amygdala or medial amygdala lesions. These results suggest that the amygdala, especially the anterior part of the central and basolateral nuclei, plays an important role in conflicting behavior of rats in the water lick test. In a second experiment, the effects of benzodiazepine- and GABA-antagonists on the anticonflict action of diazepam, zopiclone, and phenobarbital injected into the anterior part of central and basolateral amygdala were examined, also using a water lick suppression test. A dose-dependent anticonflict action was produced by systemic administration as well as by intra-amygdala injection of diazepam, zopiclone, lormetazepam, flurazepam and phenobarbital. The order of potency was lormetazepam greater than zopiclone greater than or equal to diazepam greater than flurazepam greater than or equal to phenobarbital for both routes of injection. The anticonflict effects of diazepam and zopiclone injected into the amygdala were completely reversed by Ro15-1788 and beta-CCM but not by bicuculline, while the anticonflict effect of phenobarbital was reversed by beta-CCM but not by Ro15-1788 or bicuculline. The present results strongly suggest that the anterior nuclei of central and basolateral amygdala are important sites of action of antianxiety drugs, and that an anticonflict action produced by intra-amygdala injection of benzodiazepines or barbiturate is mediated through the different receptor mechanisms.

The effect of a selective phosphodiesterase inhibitor, rolipram, on muricide in olfactory bulbectomized rats

In order to evaluate the potential usefulness of the drug as an antidepressant, acute and chronic effects of rolipram, a selective inhibitor of Ca2+- and calmodulin-independent cyclic AMP phosphodiesterase were investigated on muricide in olfactory bulbectomized (OB) rats. Upon single administration to OB rats, rolipram at a dosage of 1 mg/kg body weight suppressed the muricide for 2 hr after its administration. As a consequence of daily administration of rolipram, however, the incidence of muricide at 24 hr after the administration was decreased, and more than 60% of the rats did not exhibit the muricide on the 12th day. After the cessation of the administration, the incidence of the muricide returned to the initial level. The suppression of the muricide was not antagonized by several kinds of neurotransmitter blockers. Administrations of phosphodiesterase inhibitors and dibutyryl cyclic AMP as well as desipramine and clomipramine also suppressed the muricide dose-dependently. Repeated administration of desipramine also gave results similar to those of rolipram: repetition of a short suppression on the muricide was followed by the appearance of a long-lasting suppression. Differently from rolipram and desipramine, dibutyryl cyclic AMP did not cause long-lasting suppression, and even the direct effect (75% suppression) observed 30 min after its administration on the first day disappeared during its repeated administration for 14 days. From these results, rolipram was considered to show an antidepressant effect through the inhibition of Ca2+- and calmodulin-independent cyclic AMP phosphodiesterase.

Changes in [3H]-imipramine binding sites in relation to muricide following olfactory bulbectomy and the effect of nomifensine in brain of rats

The effects of olfactory bulbectomy (OB) and nomifensine (NOM) on the binding of [3H]-imipramine (3H-IMP) in brain of rat were investigated. Seventy-five per cent of OB rats exhibited muricide. Acute NOM suppressed muricide in 55% and chronic NOM suppressed it in 60 80% of OB rats. In killer rats, OB increased Bmax of high-affinity (HA) and low-affinity sites (LA) in cortex (Cx) and both Bmax and KD of HA in amygdala (AMG). In rats with muricide suppressed by acute NOM 10 mg.kg-1 i.p., Bmax and KD of HA in Cx and of both HA and LA in AMG were reduced. Injection of NOM for 10 days produced further reduction of Bmax, especially of HA binding in Cx. Neither OB nor NOM exerted any significant effect on binding constants in caudate-putamen and hypothalamus. The possible relation between the changes of 3H-IMP binding, exhibition of muricide by OB rats and the antimuricidal activity of NOM are discussed.

A selective kappa-opioid agonist, U-50,488H, blocks the development of tolerance to morphine analgesia in rats

The development of tolerance to morphine analgesia was completely blocked by the coadministration of a selective kappa-opioid agonist, U-50,488H at doses of 3.2 or 10 mg/kg i.p. These doses of U-50,488H exerted no analgesic effect by themselves and did not affect the analgesia induced by 10 mg/kg of morphine. The analgesic effect of morphine was restored when 10 mg/kg of U-50,488H was coinjected in morphine-tolerant rats. These findings suggest that activation of the kappa-opioid system prevents the development of tolerance to morphine analgesia.

Stimulatory action of gamma-aminobutyric acid on catecholamine secretion from bovine adrenal chromaffin cells measured by a real-time monitoring system

The present study was designed to evaluate the role of gamma-aminobutyric acid (GABA) in the secretory function of cultured chromaffin cells using the method of real-time monitoring. GABA evoked the secretion of catecholamines (CA) from adrenal chromaffin cells in a dose-dependent manner. Bicuculline 10(-5) M inhibited the stimulatory action of GABA. Diazepam 5 X 10(-6) and 2.5 X 10(-5) M facilitated the secretory response evoked by 7 X 10(-5) M GABA by 22% and 96%, respectively, which was antagonized by Ro 15-1788. This finding suggests that GABA-benzodiazepine receptor coupling can function in the secretion of CA from the adrenal chromaffin cells in a manner similar to that observed in the brain. GABA-evoked release of CA was reduced by 1 microM nifedipine to 16% of control, suggesting the involvement of voltage-sensitive Ca2+ channels in the mechanisms of the CA-releasing action of GABA in these cells. From these findings, the involvement of GABAergic mechanisms in the regulation of adrenal medullary function can be proposed.

[Behavioral effects of quinupramine, a new tricyclic antidepressant]

The effects of a new tricyclic antidepressant quinupramine (5-(3-quinuclidinyl)-10,11-dihydro-5H-dibenz [b, f] azepine) on various animal behaviors were examined in mice and rats and compared with those of imipramine, amitriptyline and maprotiline. Quinupramine antagonized haloperidol-induced catalepsy and tetrabenazine-induced ptosis and potentiated methamphetamine- and apomorphine-induced stereotyped behavior. These effects were almost the same as or even more potent than those of imipramine and amitriptyline. Quinupramine decreased locomotor activity in mice, but potentiated methamphetamine-induced hyperactivity to a greater degree than imipramine and amitriptyline. On the other hand, quinupramine inhibited muricide in accumbens-lesioned rats, but did not prominently inhibit muricide in olfactory-bulbectomized and raphe-lesioned rats. Quinupramine decreased the duration of immobility in low doses without affecting locomotor activity, and this effect was almost the same as that of imipramine and amitriptyline and more potent than that of maprotiline. Quinupramine antagonized physostigmine lethality and oxotremorine-induced tremor, suggesting that quinupramine has a central anticholinergic action. Quinupramine, like imipramine and amitriptyline, has no effect on conditioned avoidance behavior. In conclusion, quinupramine generally has the same behavioral profile as typical tricyclic antidepressants, but it has somewhat different effects from imipramine and amitriptyline since quinupramine has a potent central anticholinergic and a weak antimuricide effect.