The curative efficacy of auricular comprehensive therapy on menstrual migraine and its effect on serum prostaglandin

OBJECTIVES

To observe the curative efficacy of auricular comprehensive therapy on menstrual migraine(MM) and its effect on serum prostaglandin F2α(PGF2α), prostaglandin E2(PGE2) contents and ratio, so as to explore its possible mechanism.

METHODS

A total of 66 patients with MM of liver-fire syndrome were randomly divided into observation group (33 cases, 2 cases dropped off) and control group (33 cases, 2 cases dropped off), and 20 healthy women were included in the normal group. Patients in the control group were given flunarizine hydrochloride capsules orally, twice a day, for 3 consecutive weeks. Patients in the observation group were treated with auricular comprehensive therapy, starting 2-5 days before menstrual cramps, once a week, for a total of 3 weeks. The visual analogue scale (VAS) and migraine score were evaluated before and after treatment, and follow-up for 1 and 2 menstrual cycles. Serum PGF2α and PGE2 contents were measured before and after treatment, and the PGF2α/PGE2 ratio was calculated. The clinical effective rates in the two groups were calculated.

RESULTS

After treatment and follow-up for 1 and 2 menstrual cycles, the VAS scores, headache degree, the frequency and duration of headache attacks, as well as accompanying symptoms of the observation and control groups were lower than those before treatment(P<0.05), and those of the observation group was lower than those of the control group(P<0.05). Before treatment, the PGF2α contents in the observation and control group were significantly higher(P<0.05), while the PGE2 contents lower(P<0.05) and PGF2α/PGE2 ratio higher(P<0.05) than those in the normal group. After treatment, the serum PGF2α contents in the observation and control group were significantly reduced compared with which before treatment(P<0.05), and were lower in the observation group than that in the control group (P<0.05). The serum PGE2 contents in the observation and control groups were significantly increased after treatment compared with which before treatment(P<0.05), with the contents in the observation group higher than that in the control group(P<0.05). The serum PGF2α/PGE2 ratio in the observation and control group was significantly reduced after treatment compared with which before treatment(P<0.05), with the control group higher than the normal group(P<0.05), and the observation group lower than the control group(P<0.05). The clinical effective rate of the observation group was 93.5% (29/31), and that of the control group was 77.4% (24/31). The effective rate of the observation group was significantly higher than that of the control group(P<0.05).

CONCLUSIONS

The curative efficacy of auricular comprehensive therapy on MM with liver-fire syndrome is significantly better than that of oral flunarizine hydrochloride capsules, especially in relieving hea-daches, reducing the frequency and duration of headache attacks, as well as accompanying symptoms. Its mechanism may be related to regulating the abnormal PGF2α and PGE2 contents of patients and reducing the ratio of PGF2α/PGE2.

Abnormal heart rate variability and its application in predicting treatment efficacy in patients with chronic migraine: An exploratory study

AIM

This study aimed to investigate the extent of autonomic nervous system dysfunction in patients with chronic migraine using heart rate variability analysis. In addition, we explored the potential association between heart rate variability and treatment outcomes in patients receiving preventive treatment.

METHODS

In this cross-sectional and prospective study, we compared heart rate variability profiles in 81 preventive-naïve chronic migraine patients and 58 healthy controls. In addition, treatment responses of patients, who received a 12-week treatment with flunarizine, were assessed in relation to baseline heart rate variability.

RESULTS

We observed that chronic migraine patients had a reduced heart rate variability, signifying autonomic dysfunction in comparison to healthy controls. Furthermore, patients presenting normal heart rate variability, characterized by a standard deviation exceeding 30 milliseconds in normal-to-normal RR intervals, experienced a superior response to flunarizine treatment. This improvement was exemplified by a significantly larger reduction in monthly headache days for patients with higher heart rate variability compared to those with lower heart rate variability: -9.7 (5.9) vs. -6.2 (6.0) days (p = .026).

CONCLUSIONS

Autonomic dysfunction occurs in chronic migraine as evaluated by heart rate variability. A preserved function is associated with a better treatment outcome to flunarizine.Trial registration: Neurologic Signatures of Chronic Pain Disorders, NCT02747940. Registered 22 April 2016, https://clinicaltrials.gov/ct2/show/NCT02747940.

Epilepsy with eyelid myoclonia in the setting of de novo pathogenic variant in ATP1A3

Mutations in the ATP1A3 gene have been associated with several syndromes, including rapid-onset dystonia-parkinsonism, alternating hemiplegia of childhood, and cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss. In this clinical commentary, we report a 2-year-old female patient with de novo pathogenic variant in the ATP1A3 gene associated with an early-onset form of epilepsy with eyelid myoclonia. The patient had frequent eyelid myoclonia occurring 20-30 times per day, without loss of awareness or other motor manifestations. EEG showed generalized polyspikes and spike-and-wave complexes maximal in the bifrontal regions, with prominent eye closure sensitivity. A sequencing-based epilepsy gene panel revealed a de novo pathogenic heterozygous variant in ATP1A3. The patient showed some response to flunarizine and clonazepam. This case highlights the importance of considering ATP1A3 mutations in the differential diagnosis of early-onset epilepsy with eyelid myoclonia and the potential benefit of flunarizine in improving language and coordination development in patients with ATP1A3-related disorders.

Topical flunarizine reduces IOP and protects the retina against ischemia-excitotoxicity

PURPOSE

To determine whether topical application of flunarizine reduces intraocular pressure (IOP) and acts as a retinal neuroprotectant and to compare the effectiveness of flunarizine with betaxolol and nifedipine at reducing the influx of calcium and sodium.

METHODS

Ischemia was delivered to the rabbit retina by raising the IOP. After 3 days, a flash electroretinogram (ERG) was recorded, and the retina processed for the localization of certain antigens. In the rat, N-methyl-D-aspartate (NMDA) was injected intravitreally, and 8 days later, the retinas were analyzed for the localization of Thy-1 or the relative amounts of mRNAs for antigens located to ganglion cells or photoreceptors. Rats and rabbits received topical flunarizine or vehicle before and after ischemia or NMDA. IOP was measured in rabbits after a single topical application of 2% flunarizine. Studies were conducted on isolated rat retinas, cortical cultures, and brain synaptosomes to compare the effectiveness of flunarizine with nifedipine and betaxolol at reducing the influx of calcium or sodium.

RESULTS

Changes in rabbit retinal choline acetyltransferase and parvalbumin immunoreactivities and the b-wave of the ERG caused by ischemia-reperfusion were blunted by topical treatment with flunarizine. Similarly, NMDA induced reductions in Thy-1 immunoreactivity and mRNA for rat ganglion cell antigens (Thy-1 and neurofilament light form) were counteracted by topical application of flunarizine. Topical application of 2% flunarizine significantly lowered the IOP in rabbits over a period of 5 hours. Flunarizine was more effective than betaxolol and much stronger than nifedipine at attenuating veratridine-induced influx of sodium into synaptosomes. Nifedipine, flunarizine, and betaxolol all reduced the NMDA-induced influx of calcium into the isolated retina or cortical neurons, but betaxolol was the least effective.

CONCLUSIONS

Topically applied flunarizine reduces IOP and attenuates injury to the whole of the retina, including the ganglion cells. The neuroprotective action of flunarizine is to reduce the influx of calcium and sodium into stressed neurons. The potent effect of flunarizine on sodium influx would be particularly protective to axons.

Effects of flunarizine on recovery of cerebral function following cardiac arrest

A 10-min cardiac arrest was produced in alfentanil-anesthetised dogs by electrical fibrillation of the heart. Recovery of cerebral function was monitored by 3 separate EEG techniques and visual assessment of neurologic deficit. The EEG techniques were visual scoring, broad-band power spectral analysis and period-amplitude analysis. The treatment group (n = 8) received flunarizine (0.1 mg/kg i.v.) at the beginning of resuscitation, while control animals (n = 8) were given the drug vehicle. A significant improvement in the visual EEG score and neurologic deficit 6 h after insult was noted in flunarizine-treated dogs. The extent of neurologic recovery was significantly correlated with the visual EEG score, with the relative power in the alpha frequency band (7.5-13.5 c/s) and with the percentage of zero-cross frequency.

Mitral valve prolapse and ventricular arrhythmias: observations in a patient with a 20-year history

INTRODUCTION

Ventricular arrhythmias are a common feature in patients with mitral valve prolapse. In an attempt to determine the origin and underlying electrophysiologic mechanism, we describe a patient with ventricular fibrillation, exercise-induced ventricular tachycardia (VT), and, at the time of diagnosis, prolapse of the posterior mitral valve leaflet without mitral regurgitation.

METHODS AND RESULTS

Treatment with beta-blockade and diphenylhydantoin prevented the occurrence of malignant ventricular arrhythmias for more than 17 years. Discontinuation of the therapy resulted in an immediate reappearance of the VT, which, despite the marked enlargement of the left ventricle (secondary to development of severe mitral valve regurgitation), had a strikingly similar morphology. For hemodynamic reasons, the patient was finally selected for valve replacement. Detailed pre-, peri-, and postoperative studies were performed, including administration of flunarizine, body surface mapping, construction of perioperative epicardial and endocardial maps, and studies of the excised muscles in vitro.

CONCLUSIONS

Delayed afterdepolarization-induced triggered activity is the mechanism of VT in this mitral valve prolapse patient. The trigger is provided by isolated ventricular premature complexes elicited by a different electrophysiologic mechanism, possibly reentry, which is related to stretch and presumably to fibrosis of the papillary muscles.

Effect of GABA-ergic drugs on flunarizine-induced seizures in rabbits

In this study the authors have evaluated the effects of common antiepileptic drugs given alone or in combinations with baclofen on seizures evoked by intravenous flunarizine in rabbits. The abolition of clonic and clonic-tonic convulsions was taken as the end point. Baclofen was able to inhibit convulsions only in a relatively high dose (5 mg/kg). Diazepam (1.5 mg/kg) and clonazepam (2 mg/kg) completely abolished clonic seizures. Valproate (20 mg/kg) inhibited clonic seizures and remained without effect on tonic convulsions. Other antiepileptics such as carbamazepine and acetazolamide were found inactive in this respect. Moreover, combinations of acetazolamide (100 mg/kg) and carbamazepine (50 mg/kg) with baclofen (2 mg/kg) had no anticonvulsant effect. Thus, mainly GABA modulatory drugs reveal significant action against flunarizine-induced seizures.

Flunarizine allows differentiation between mechanisms of arrhythmias in the intact heart

The calcium antagonist flunarizine suppresses pathologic accumulation of calcium intracellularly without affecting the fast sodium or the slow calcium channel. To establish its value in differentiating between mechanisms of arrhythmias in the canine heart, the effect of flunarizine was investigated on ventricular tachycardia (VT) induced by ouabain intoxication or occurring 16-24 hours after occlusion of the left anterior descending coronary artery. Four groups of dogs were studied. Group 1 consisted of 13 animals with VT induced by ouabain intoxication (triggered-activity group). Group 2 included nine dogs in whom VT developed 16-24 hours after occlusion of the left anterior descending coronary artery (abnormal automaticity group). Group 3 included six dogs with normally conducted sinus beats, whereas group 4 consisted of six animals having a ventricular escape rhythm. With the exception of group 3, all dogs had surgically induced complete atrioventricular block. All animals were studied while conscious and without premedication. In groups 1 and 2, 2-3 mg/kg flunarizine was given intravenously after VT had persisted for at least 20 minutes. In groups 3 and 4, 2 mg/kg flunarizine was given after the rhythm was registered for 20 minutes. The cycle lengths of the different rhythms were compared before and after flunarizine. In group 1, flunarizine increased the cycle length of the VT from 300 +/- 30 to 410 +/- 50 msec (p less than or equal to 0.001). Termination of VT was seen in 11 out of 13 animals. In group 2, flunarizine resulted in a nonsignificant shortening of the RR interval from 450 +/- 60 to 440 +/- 60 msec. Persistent termination was observed in only one of nine dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Muscarinic cholinergic enhancement of inositide turnover in cerebral nerve endings is not mediated by calcium uptake

Muscarinic cholinergic stimulation of rat cerebral nerve endings incubated with 32Pi causes an enhancement of the labeling of phosphatidic acid (PA) and phosphatidylinositol (PI). The involvement of Ca2+ in the stimulation of PA and PI labeling by carbamylcholine (CCh) was investigated. Enhancement of Ca2+-influx with veratridine and the Ca2+-ionophore A23187 caused a vast decrease of the labeling of the polyphosphoinositides, which was not accompanied by an enhancement of the labeling of PA and PI. The dihydropyridine Ca2+-agonist BAY K8644 did not affect phospholipid labeling. A23187, veratridine and BAY K 8644 did not enhance stimulation of the labeling of PA and PI by CCh. When Ca2+ was omitted from the incubation, A23187 caused an enhancement of basal and CCh-stimulated labeling of PA and PI, possibly indicating a particular feature of A23187 unrelated to its iontophoretic properties. The Ca2+-channel antagonists nimodipine, verapamil and flunarizine were virtually without effect on basal and CCh-stimulated labeling of PI and PA. These data support the notion that the muscarinic cholinergic inositide response is not mediated or controlled by Ca2+-flux.

Ineffectiveness of organic calcium channel blockers in antagonizing long-term potentiation

Evidence has accumulated suggesting that the presence of calcium is critical for development of hippocampal long-term potentiation (LTP). However, there is a paucity of information about whether calcium's role in LTP is pre- or postsynaptic. In the present study, we examined the effectiveness of nitrendipine, verapamil, flunarizine and the benzodiazepine diazepam in: blocking voltage-dependent calcium channels; blocking synaptic transmission; and preventing development of LTP. Using the in vitro slice preparation, we obtained intracellular and extracellular recordings from guinea pig hippocampal CA1 pyramidal cells. At the cellular level, all 4 drugs were ineffective in blocking voltage-dependent calcium spikes (TTX resistant) and the calcium-dependent afterhyperpolarization. Verapamil and diazepam appeared to antagonize synaptic transmission, as reflected in smaller population spike amplitudes. Development of long-term potentiation was not affected by the presence of verapamil, flunarizine and diazepam. Nitrendipine appeared to reduce the percentage of slices exhibiting LTP; however, ethanol, the vehicle used to dissolve nitrendipine, was shown in separate experiments to reduce the percentage of slices exhibiting LTP. These results suggest that neither the organic calcium channel blockers--nitrendipine, verapamil, and flunarizine--nor micromolar concentrations of diazepam are potent blockers of extrasynaptic voltage-sensitive calcium channels in hippocampus. They thus cannot be used to demonstrate a specific pre- or postsynaptic calcium role in LTP.

Calcium channel antagonists and the treatment of migraine

Despite ongoing dispute over the pathophysiologic basis of migraine, the vasospastic theory of pathogenesis has brought to the forefront a promising class of new antimigraine agents, the Ca2+ channel antagonists. Voltage-dependent Ca2+ channels, integral membrane proteins that permit extracellular Ca2+ to enter cells down their electrical and concentration gradients, have a universal role in stimulus-response coupling in excitable cells. Thus, they participate in translating electrical excitation into secretory and contractile events. Ca2+ channel antagonists, a structurally diverse group of organic compounds, inhibit ion flux through voltage-dependent Ca2+ channels by binding to specific, channel-associated drug receptor sites and thereby reduce the frequency of channel opening in response to membrane depolarization. Ca2+ channels in cardiac muscle, smooth muscle, and neurons all exhibit high affinity for Ca2+ channel antagonists, although neurons also contain a population of drug-resistant channels. Extensive clinical experience in the use of Ca2+ channel antagonists has accumulated from their application to nonneurologic, especially cardiovascular, disorders. Three such drugs, nifedipine, verapamil, and diltiazem, are currently available in the United States, although none are specifically approved for use in migraine. Other agents, such as nimodipine, are likely to be released in the near future. A large number of clinical studies have now addressed the efficacy of Ca2+ channel antagonists in the prophylaxis of migraine headache. Dihydropyridines (nifedipine and nimodipine), phenylalkylamines (verapamil), diphenylalkylamines (flunarizine), and benzothiazepines (diltiazem) have all been examined, and a beneficial effect has been noted in each case. The limited directly comparative data currently available and the difficulties involved in comparing the results of different studies do not presently support claims of superiority for any single agent. This is an issue that will require attention as these drugs achieve more widespread use in migraine. Existing evidence suggests that flunarizine, verapamil, nifedipine, and nimodipine are effective prophylactic agents in both common and classic migraine. Nifedipine and nimodipine also appear to be valuable for the treatment of cluster headache. Two case reports describing favorable responses to flunarizine in childhood hemiplegic migraine are the only available data concerning the utility of these drugs in "complicated" migraine syndromes. The role of Ca2+ channel antagonists in treating "muscle contraction" or "tension" headache has not been addressed in any detail.(ABSTRACT TRUNCATED AT 400 WORDS)

Augmentation by calcium channel antagonists of general anaesthetic potency in mice

The effects of three kinds of calcium channel antagonists on the anaesthetic potencies of ethanol, pentobarbitone and argon were examined in mice. Ethanol and pentobarbitone anaesthetic potencies in mice were significantly increased by verapamil 10 mg kg-1, flunarizine 40 mg kg-1 and nitrendipine 100 mg kg-1. Argon anaesthetic potency was significantly increased by nitrendipine 50 mg kg-1 and 100 mg kg-1 in a dose-related fashion. Even at very high doses the calcium channel antagonists did not produce anaesthesia by themselves. At the doses used the calcium channel antagonists did not affect the blood concentrations of ethanol, 2 h, or pentobarbitone, 15 min, after anaesthetic administration.

Anticonvulsant properties of flunarizine on reflex and generalized models of epilepsy

The anticonvulsant activity of 1-bis(4-fluorophenyl)methyl-4-(3-phenyl-2-propenyl)-piperazine, flunarizine, was studied after intraperitoneal administration in DBA/2 mice (seizures induced by sound), intravenous administration in Papio papio (myoclonus induced by photic stimulation) and oral administration in Wistar rats (seizures induced by cefazolin). Protection against sound-induced seizures was observed after intraperitoneal administration of flunarizine (5-40 mg/kg). The ED50 for suppression of tonic, clonic and wild running phases of sound-induced seizures was 3.3, 9.8 and 17.5 mg/kg, respectively. This protective action was significantly reduced by pretreatment with aminophylline (50 mg/kg, i.p.). In photosensitive baboons flunarizine (0.5-1.0 mg/kg, i.v.) provided partial protection against myoclonic responses to stroboscopic stimulation. After flunarizine (2 mg/kg, i.v.) this protection lasted for more than 5 hr (and was complete at 2-3 hr). Cefazolin-induced seizures in rats were prevented by administration of flunarizine (20-40 mg/kg, orally). The ED50 for the suppression of tonic and clonic seizures evoked by subsequent intravenous administration of cefazolin was 25 mg/kg. The protective effects of flunarizine (40 mg/kg, orally) were maximal after 3-6 hr and were maintained for 16-24 hr. Behavioural effects of flunarizine included signs of sedation in both mice and rats. Tolerance to the antiepileptic effects of flunarizine was not seen after chronic treatment in rats. The role of purinergic receptors and of calcium entry blockade in the anticonvulsant action of flunarizine requires further study.

Cross-clamping of the thoracic aorta. Influence of aortic shunts, laminectomy, papaverine, calcium channel blocker, allopurinol, and superoxide dismutase on spinal cord blood flow and paraplegia in baboons

There is a high incidence of paraplegia associated with thoracic aortic cross-clamping, even when cardiopulmonary bypass or shunts are used. In 56 adult baboons, spinal cord blood flow (SCBF), vascular anatomy, and paraplegia rates were evaluated. Tissue blood flow was measured by radioactive microspheres. Various procedures were used to increase SCBF and to prevent ischemia-reperfusion injury. It was found that the rate of paraplegia was inversely correlated with neural tissue ischemia (SCBF) and directly correlated with reperfusion hyperemia. Two methods completely prevented paraplegia. These two methods were a thoracic shunt with occlusion of the infrarenal aorta or cerebrospinal fluid drainage plus intrathecal papaverine injection, both of which were associated with an increased SCBF. Furthermore, papaverine dilated the anterior spinal artery (ASA) (p = 0.007) and increased the blood flow through the lower ASA. Whereas procedures utilizing a calcium channel blocker (flunarizine), allopurinol, superoxide dismutase (SOD), laminectomy alone, and a thoracoabdominal shunt not perfusing the arteria radicularis magna (ARM) all failed to prevent paraplegia, allopurinol (p = 0.026) and SOD (p = 0.004) did prevent gastric stress lesions, indicating that their failure to prevent paraplegia was not due to a lack of activity. Of great clinical interest is that, if a shunt is used and the ARM is perfused, infrarenal aortic cross-clamping increases SCBF, thus preventing paraplegia. Intrathecal application of papaverine proved to be even more effective in increasing SCBF and also completely prevented paraplegia. As this is a safer procedure than the insertion of shunts, this is the method of choice for the prevention of paraplegia associated with thoracic aortic cross-clamping. The preliminary trial using intrathecal papaverine in human beings has thus far shown no adverse side effects from the drug, and no paraplegia has occurred.

Nifedipine and flunarizine block amphetamine-induced behavioral stimulation in mice

Sixteen calcium channel inhibitors (CCI's) were tested in a model utilizing amphetamine-induced behavioral stimulation in mice. Nifedipine, flunarizine and possibly PY 108-068 were effective in blocking amphetamine-induced locomotor stimulation. Verapamil, diltiazem and many other CCI's were ineffective in this experimental paradigm.

Parkinsonism, tardive dyskinesia, akathisia, and depression induced by flunarizine

12 subjects, 8 women and 4 men, presented with extrapyramidal motor signs and psychic depression after treatment with flunarizine for between 3 weeks and 15 months. One woman presented with severe symptoms and 20 months after stopping flunarizine she still had dyskinesia and akathisia. The other patients showed partial or complete improvement after withdrawal of the drug.

Measurement of ischemic changes in cerebral blood flow by the hydrogen clearance technique and brain cortical temperature. Influence of flunarizine

In dogs global cerebral ischemia was produced by clamping reversibly the left subclavian and brachiocephalic arteries, supplying the head. The intercostal arteries were ligated permanently. Cerebral blood flow (CBF) was measured discontinuously using a hydrogen saturation-desaturation technique. Clamping of the former two vessels caused an increase in systemic blood pressure. When this increase was not blunted by previous splenectomy and blood withdrawal a still important CBF remained during the clamp. However, if this rise in blood pressure was impaired, CBF decreased to 9 +/- 8% (mean +/- S.D., n = 14) of the pre-ischemic value. Flunarizine is known to have anti-hypoxic/ischemic properties. The influence of this drug (0.1 mg/kg i.v.), injected 10 min after the beginning of a 30-min ischemia period, on the post-ischemic CBF was investigated. Two-three hour after ischemia CBF was significantly lower in the solvent-treated animals than in the flunarizine-treated group, in which CBF approached the preischemic values. Changes in CBF were also followed continuously by measurement of the variations of brain versus aortic temperature. It was analyzed what information this can provide on CBF.

Calcium channel antagonists. Omega-conotoxin defines a new high affinity site

The omega-conotoxins, a class of Ca2+ channel antagonists from fish-hunting marine snails, have recently been described (Olivera, B. M., McIntosh, J. M., Zeikus, R., Gray, W. R., Varga, J., Rivier, J., de Santos, V., and Cruz, L. J. (1985) Science, 230, 1338-1343). One of these peptide neurotoxins, omega-conotoxin GVIA, was radiolabeled with iodine, and the 125I-labeled toxin was shown to bind specifically to high affinity sites on chick brain synaptosomes. The toxin-receptor complex was extremely stable; addition of an excess of unlabeled toxin did not cause significant displacement of the labeled toxin after 2 h. Binding competition data suggest that omega-conotoxin defines a new high affinity receptor site affecting voltage-activated Ca2+ channels, distinct from both the verapamil and dihydropyridine target sites.

Effects of verapamil and alcohol on blood flow, melphalan uptake and cytotoxicity, in murine fibrosarcomas and human melanoma xenografts

Verapamil had previously been shown to increase cellular melphalan uptake and cytotoxicity in fibrosarcomas, and increased the area under the blood concentration versus time curve (AUC) for melphalan in CBA mice. Verapamil (10 mg kg-1 i.p.) had no effect on the fractional distribution of cardiac output (FDCO), measured with 86Rb-rubidium chloride, to subcutaneous fibrosarcomas. 14C-Melphalan uptake by FS13 fibrosarcomas was increased 60 min after verapamil (10 mg kg-1 i.p.), but not after lower doses which did not affect the AUC. Flunarizine (5 mg kg-1 i.p.) also had no effect on FDCO to FS13 fibrosarcomas, and tended to increase 14C-melphalan content of blood and the fibrosarcomas and to promote growth delay by melphalan. Alcohol increased FDCO to FS13 fibrosarcomas, maximally at a 1:20 dilution in saline, but had no effect on 14C-melphalan uptake or growth delay. Thus, melphalan cytotoxicity correlated with tumour melphalan uptake, and both followed changes in the AUC for melphalan but not changes in FDCO. In these murine fibrosarcomas melphalan uptake and cytotoxicity were not limited by blood flow. In subcutaneous human melanoma HX46 xenografts, verapamil had no effect on the FDCO, nor on 14C-melphalan uptake, and did not affect blood 14C-melphalan levels, suggesting absence of effects on the AUC and on cellular uptake. Alcohol did not increase the FDCO to HX46 xenografts, providing evidence for a different vascular supply.

A trial of flunarizine in the treatment of Duchenne muscular dystrophy

Twenty-seven boys with Duchenne muscular dystrophy (DMD) entered a double-blind controlled trial of treatment with the calcium antagonist flunarizine. They were matched for age and disability. At monthly intervals, muscle power, functional ability, locomotor score, contractures, and forced vital capacity were measured by a team not involved in clinical care. Over a period of 1 year, flunarizine in a dose of up to 0.25 mg/kg/day had no effect on the clinical course of the disease.

Flunarizine limits hypoxia-ischemia induced morphologic injury in immature rat brain

We examined the impact of pre-treatment with the calcium antagonist flunarizine on the development of hypoxic-ischemic brain injury in the immature rat. Unilateral carotid artery ligation and subsequent exposure to 2 hours of 8% oxygen in 7-day-old rats was used as a model for perinatal hypoxic-ischemic encephalopathy. This procedure leads to atrophy in the cerebral hemisphere ipsilateral to carotid occlusion, with prominent foci of neuronal infarction in the caudate-putamen (striatum). The morphologic injury develops after 1 1/2 hours of hypoxia; and there is an equivalent time threshold for duration of hypoxic exposure needed to acutely stimulate dopamine release in the ipsilateral striatum. Parenteral administration of 30 mg/kg of flunarizine before hypoxic exposure limited both the release of dopamine acutely and the extent of morphologic damage observed two weeks after the insult. Oral administration of 30 mg/kg of flunarizine in a different vehicle prevented morphologic damage but had no effect on stimulated dopamine release. The drug vehicle for the parenteral preparation also prevented tissue injury, but to a lesser degree than flunarizine. However the parenteral vehicle was equipotent with parenteral flunarizine in limiting acute stimulation of dopamine release. The results demonstrate that flunarizine has potent neuroprotective properties against morphologic brain injury from hypoxia-ischemia, acting by a mechanism which is independent of effects on dopamine release.

Isolated rat cardiac myocytes as an experimental model to study calcium overload: the effect of calcium-entry blockers

Calcium overload and the effect of a series of calcium-entry blockers were studied in isolated adult cardiac myocytes from the rat challenged with veratrine. The isolation procedure resulted in a high yield of individual rod shaped, calcium tolerant myocytes. After incubation with veratrine, an alkaloid which induces both sodium and calcium influx, 93% of the myocytes became calcium intolerant: the quiescent rod shaped cells vigorously contracted after 30 sec of contact with veratrine and contracture (round cells) ensued within 1 min. Exposure for 30 min to various doses of calcium-entry blockers prior to veratrine addition resulted in the prevention of contracture, the degree of protection depending on the type and the concentration of calcium-entry blocker. Among the different calcium-entry blockers tested, the diarylalkylpiperazines lidoflazine, cinnarizine and flunarizine were protective from the 10(-7) M concentration onwards. Nicardipine was protective at the 10(-6) M and 10(-5) M concentrations, verapamil at 10(-5)M only while other blockers of the "slow channel" type (diltiazem and nifedipine) were not protective in the concentration range tested. This study shows that isolated myocytes represent a valid model for pharmacological investigations. The results with the calcium-entry blockers stress the heterogeneity of the different series of calcium-entry blockers.

Neurotensin effect on dopamine release and calcium transport in rat striatum: interactions with diphenylalkylamine calcium antagonists

The release of dopamine was investigated in rat striatal slices exposed in vitro to neurotensin. This peptide increased basal and K+-evoked dopamine release. Moreover neurotensin antagonized the flunarizine-induced inhibition of K+-stimulated dopamine release. The K+-evoked 45Ca2+ accumulation was also inhibited by flunarizine. This effect was antagonized by neurotensin. The results suggest that dopamine release in rat striatum is regulated by different molecular events also of peptidergic nature having as possible mechanism of action an influence on calcium ion movements.

Flunarizine-pizotifen single-dose double-blind cross-over trial in migraine prophylaxis

The results of a double-blind cross-over clinical trial involving 27 patients with classical or common migraine are described to compare the prophylactic effect of the calcium entry blocker flunarizine with that of pizotifen. Duration of the treatment was two months, with an evening single-dose administration of both drugs. For most parameters, there was no definite difference between flunarizine and pizotifen in migraine prophylaxis. It has been demonstrated previously that pizotifen is an effective drug in migraine prophylaxis, and these results suggest that flunarizine is effective, too. Weight gain as a side effect was less frequent and less severe with flunarizine than with pizotifen; other side effects showed the same incidence with both drugs.

A placebo-controlled, double-blind, cross-over trial of flunarizine in common migraine

After four weeks of medication-free baseline observation, 29 patients with common migraine randomly received flunarizine (10 mg daily) or placebo for a 16-week period. After four weeks wash-out they crossed treatments for another 16 weeks; 27 patients completed the trial. Compared with placebo, flunarizine significantly reduced the frequency of migraine attacks and the derived headache indices, but the duration and severity of single attacks remained unchanged (Mann-Whitney U-test). The effect of flunarizine increased during the 16-week treatment period and during the last four weeks the number of migraine attacks reduced to 50% compared to the wash-out period. The only side-effect of flunarizine was mild daytime sedation in three patients. It is concluded that flunarizine is a valuable new prophylactic agent for common migraine.

Flunarizine, a calcium entry blocker, ameliorates ischemic brain damage in the rat

The effects of flunarizine, a calcium entry blocker, were evaluated in a long-term survival model of ischemia in rats. One group of animals received the drug orally at 24 and 4 h prior to the insult (40 mg X kg-1 X dose-1). Another group was given flunarizine following the insult, intravenously at 5 min (0.1 mg X kg-1), and orally at 8 and 24 h (40 mg X kg-1 X dose-1). A third group received the solvent for the oral suspension on the same schedule as the pretreated group. Six animals from each group were subjected to 9 min ischemia and recovery of 7 days, at which time the brains were harvested for histologic study. In another six animals from each group, cortical metabolites and fatty acids were determined during early recirculation. Local cerebral blood flow was measured at 60 min recirculation in a third set of animals. Flunarizine significantly improved histological outcome (fewer irreversibly damaged cells) in both treatment groups. This amelioration was not related to improvement of cerebral blood flow during the period of delayed hypoperfusion, nor the postischemic levels of high-energy phosphates or free fatty acids.

Calcium antagonists in the prevention of motion sickness

Flunarizine is a calcium antagonist which has proved clinically useful in controlling chronic vertigo. In a double blind crossover trial 10 subjects were used to compare the electronystagmic responses to motion in patients taking flunarizine, prochlorperazine maleate, or placebo. Flunarizine is shown to be a powerful peripherally acting labyrinthine suppressant, with application in the prevention of motion sickness. Flunarizine produces none of the central depressive side effects characteristic of antihistamines and anticholinergics, which are the conventional anti-motion sickness drugs.

Flunarizine treatment in dizzy patients with vestibular hyperreactivity and hyperventilation

Flunarizine (10 mg/day) was given in an open pilot study to 14 patients with the primary complaint of dizziness, who showed vestibular hyperreactivity in the velocity step (VS) test and were proven to have a hyperventilation syndrome (HVS) without any other disease. The VS test was repeated after 4-6 weeks of treatment. Twelve of these HVS patients reported alleviation of dizziness. Objective evaluation of the results of treatment was attempted by defining suitable response parameters and comparing their values to those obtained in a control group of 14 healthy volunteers tested twice with the same interval. A significant decrease in right-left asymmetry in the VS responses of the patients on drug was found.

The value of flunarizine in the treatment of tinnitus

The suppressive effect of flunarizine on tinnitus was assessed in a double-blind trial in 50 patients with tinnitus due to various causes. The duration of the study was 6 weeks. Serum levels of the drug were determined. The patient's subjective assessment of the effect was taken as criterion for the evaluation; objective tests were found to be unsuitable for this purpose. Ten of the patients suffered from dizziness as a secondary complaint. For the group as a whole, there was no difference between flunarizine and the placebo with respect to the effect on tinnitus, but in the 10 patients with dizziness as well there was a significant difference in favor of the drug. Conclusions cannot be drawn as to the reason for this divergence, because the number of patients was too small.

Verapamil as an apparent competitive antagonist of the serotonin receptor of rabbit isolated aorta

The actions of four Ca2+-antagonists (verapamil, diltiazem, nifedipine and flunarizine) were tested on serotonin- (5-HT-) induced contraction of rabbit isolated aorta. Verapamil produced a dose-dependent, parallel shift to the right of the concentration-response curve for 5-HT (pA2 approximately equal to 7.13; Schild slope approximately equal to 1.01), indicative of competitive antagonism. The effects of diltiazem, nifedipine and flunarizine were much less pronounced and best characterized as non-competitive interactions. The effect of verapamil, which likely involves its antagonism of smooth muscle 5-HT2-receptors, might be useful in explaining its therapeutic actions and/or its side-effects.

[Flunarizine in drug-resistant epilepsies of childhood and adolescence]

Therapeutic effects of flunarizine have been studied on 26 patients, aged from 9 months to 17 years, suffering for epilepsies resistant to common anticonvulsant treatment, despite proper plasmatic levels of drugs. All the cases were monitored with monthly clinical and EEG controls, neuropsychological evaluations and monitoring antiepileptic drugs plasmatic levels. At first, a study was performed on an intra-patient basis: after a basal observation during two months, an open clinical trial was started, using for three months flunarizine 5 mg a day in patients weighing over 10 kg, and 5 mg every two days in children weighing less than 10 kg. Later on, a simple blind clinical trial has been performed on 16 patients, using flunarizine or placebo for three months. The results, obtained in resistant epilepsy of children and adolescent, showed that flunarizine induced in 47.6% of cases a significant reduction of critical (stroke) frequency and intensity, together with normalization of sleeping-waking rhythm, and amelioration of attention performances (vigilance, reactivity, environmental participation). The only side-effect, noticed in 23.8% of cases, was a light diurnal sleepiness, spontaneously regressing after a few days of treatment.

Flunarizine, the vestibular system and migraine

The vestibular function was extensively investigated in 75 patients suffering from migraine. Pathological findings were present in 62 patients (82.6%). With the exception of position nystagmus, vestibular abnormalities were not related to migraine characteristics. Fifty-six patients were treated with flunarizine 10 mg daily for three months. A favourable effect on headache was obtained in 44 patients (78.5%). Flunarizine therapy influenced significantly gaze nystagmus and position nystagmus. The latter tended to be related to anti-migraine efficacy. Other electronystagmographic parameters were not substantially influenced. The authors assume that the vestibular abnormalities in migraine are side phenomena, the clinical relevance of which, at least during the headache-free phase, is not yet well understood.

[Effect of flunarizine on healing and necrosis of experimental autografts in the rat]

The influence of flunarizine on flap necrosis has been studied in rats by means of an abdominal neurovascular island skin flap model. Four groups of six rats were treated in a pretreatment phase of one week and a medication phase of four weeks with either flunarizine (2.5 mg/kg) or a placebo. Rats with flunarizine treatment over the whole period showed a significantly faster healing and less necrosis than the placebo group. The group without flunarizine pretreatment showed similar results as the control group at the first week after surgery, but from the second week on, the flunarizine effect became manifest. The skin graft model clearly demonstrates the beneficial effects of flunarizine in the prevention of tissue necrosis.

Modulation by endothelium of contractile responses in rat aorta in absence and presence of flunarizine

The possible modulation by endothelium of phenylephrine- and prostaglandin F2 alpha-induced mobilization of calcium for contraction in the rat aorta has been investigated. Contractions elicited by these and other agonists are inhibited in the presence of endothelium. For any single concentration of phenylephrine in the presence of endothelium, the initial phasic components of contractions were significantly greater, the maximal contractions were achieved sooner and were less well maintained as compared to contractions elicited in the absence of endothelium. The kinetic characteristics of contractions stimulated by single concentrations of PGF2 alpha were similar in the presence and absence of endothelium and did not exhibit initial phasic components of contraction. Sub-maximal contractions-elicited by both PGF2 alpha and phenylephrine in the absence of endothelium were inhibited to a greater extent by flunarizine 3 microM than equieffective contractions elicited in the presence of endothelium. Maximal contractions elicited by phenylephrine (1 microM) were inhibited to a similar extent by flunarizine in the presence and absence of endothelium, but maximal contractions elicited by PGF2 alpha (30 microM) were inhibited by flunarizine to a greater extent in the presence than in the absence of endothelium. It is concluded that an endothelium-derived factor, perhaps distinct from endothelium-derived relaxing factor, can modulate the ability of both phenylephrine and PGF2 alpha to mobilize calcium for contraction. This modulatory effect is associated with an enhanced mobilization of intracellular calcium. Thus, submaximal concentrations of both agonists were less dependent on extracellular calcium than on intracellular calcium to elicit contractions in the presence of endothelium, as compared to contractions elicited in the absence of endothelium.