JP2000516612A - Intramural delivery of nitric oxide enhancers to suppress lesion development after vascular injury - Google Patents

Abstract

(57) [Summary] Angiogenesis of vascular lesions is intramurally treated with L-arginine. The occurrence of restenosis is substantially reduced, and the occurrence of restenosis due to damage is prevented. An iontophoretic catheter can be used for local delivery of L-arginine. In the catheter, one electrode (28) is disposed in the catheter body (11), and the other electrode (31) is disposed in the body surface or body of the subject. Thereafter, the catheter balloon (26) is inflated and the drug enters the balloon interior (27) through the lumen (23). Activation of the power supply (30) causes the drug to cross the balloon wall (26) and contact the surrounding vessel wall (15) and vascular tissue.

Description

DETAILED DESCRIPTION OF THE INVENTION   Intramural delivery of nitric oxide enhancers to suppress lesion development after vascular injury                                   background   The long-term benefits of coronary balloon angioplasty and atherectomy may be Very high incidence of symptomatic restenosis (40-50%) in 3-6 months (Holmes et al., Am. J. Cardiol. (1984) 53: 77C-81C). Again Stenosis is due, in part, to hyperplasia of the myointimal and the vascular lumen (vessel). sel lumen) and is characterized by migration and proliferation of vascular smooth muscle cells. (Forrester et al., J. Am. Coll. Cardiiol. (1991) 17:75). 8-769). Medications to prevent restenosis remain unsuccessful . Intravascular stents have been successfully used to achieve optimal lumen gain and , Significant remodeling is prevented. However, intimal thickening However, it plays an important role in stent restenosis.   Vascular architecture maintains response to changes in paracrine factor balance. Or rebuilt. One of the substances involved in vascular homeostasis is endothelial induction. Nitric oxide (NO). NO is synthesized from the amino acid L-arginine by NO synthase. Is done. NO relaxes vascular smooth muscle and suppresses its proliferation. Also, NO suppresses the interaction between circulating blood elements and the vascular wall. NO activity is high It is reduced in cholesterol and after vascular injury. NO precursor (L-A Luginin), hypercholesterolemia, atherosclerosis or Vascular NO activity in animals and humans with endothelial vasodilator dysfunction due to restenosis Indicates recovery. Long-term enhancement of NO activity (by oral administration of L-arginine ) Have an effect on intimal hyperplasia due to hypercholesterolemia and / or vascular injury. Associated with a significant reduction. Observations with oral administration are limited to those with systemic effects. Cooke J Clin Invest 1992, 90: 1168-72; McNamara et al., Biochem Biophys Res Comm. 1993, 193: 291-6; Taguchi et al., Life Sciences 1993, 53: PL387-92; Tarry and Makh. oul et al., Arterioscler Thromb 1994, 14: 938-43; Hamon et al., Circulation 1994, 90: 1357-62; Wang et al., J Am Coll Cardiol 1994, 23: 452-8.   However, oral administration of L-arginine has potential systemic side effects. These side effects include increased hormone and insulin release during growth. This allows potentially diabetic patients (balloons for coronary or peripheral artery disease) Hyperglycemia can be exacerbated in most patients where angiogenesis is required). In addition, (30 g daily), oral L-arginine increases the growth of human breast cancer tumor cells It is clear that it can be enhanced. Therefore, selective NO activity in the vessel wall The development of an approach that allows for enhancement would be beneficial, and this effect would reduce systemic side effects. Requested without accompanying. Using arginine to enhance NO activity in the vessel wall, Reduce the incidence of restenosis caused by angiogenesis and atherectomy, but An approach was developed in which potential systemic side effects were avoided.Brief description of related literature   By intravenous oral administration of L-arginine, Animal or human with hypercholesterolemia and / or atherosclerosis Endothelial-derived nitric oxide release from blood vessels can be enhanced (1-8). Also, L-argini Long-term oral administration of atherosclerosis in atherosclerotic animals The development of arteriosclerosis is suppressed (9-10). In addition, oral administration of L-arginine Apply L-arginine to the outer surface of blood vessels using pluronic gel And restenosis after balloon injury, as in oral L-arginine (14) It is controlled (11-13). However, oral or intravenous administration of L-arginine is systemic. Has sexual side effects. Oral or intravenous L-arginine is used for growth hormone and insulin. It is known to induce phosphorus release; this leads to hyperglycemia in diabetic patients Can be exacerbated. In addition, some studies have shown that high doses of oral arginine It has been shown that the growth of tumor cells in breast cancer can be enhanced.   For intravenous administration of a plasmid construct containing a gene encoding nitric oxide synthase Thus, NO production is locally increased in the blood vessel wall, and Restenosis has been shown to be suppressed (15). However, with this approach Direct exposure of blood vessels and surgical arteriotomy, and the use of solutions containing NOS genes A long-term installation is required. This approach is coronal Movement It is impractical to prevent restenosis of the pulse. Other references include nitric oxide Inhibition of restenosis after angioplasty by administration of drugs consisting of or releasing nitric oxide It is shown that this can be done. Prolonged inhalation of nitric oxide can cause Restenosis after renal induced vascular injury is suppressed (16). NO donor (releases nitric oxide Oral administration of a drug that has vascular damage induced by balloon angiogenesis And restenosis in pig and pig models can be suppressed (17 and 18). However, oxidation Oral or inhaled administration of nitrogen or nitric oxide donors has systemic effects (hypotension, head Pain) and susceptibility to drug resistance (loss of drug action after long-term administration). Change In addition, some evidence in animal models indicates that NO donors are probably Atherosclerosis by suppressing endogenous NO activity in the vessel wall May be promoted (19 and 20). Summary of the Invention   Controls diseases associated with vascular injury, especially during angiogenesis and atherectomy Methods and devices are provided. NO precursors, especially L-arginine, Injured blood near the lesion in an amount that inhibits the disease associated with vascular injury, such as restenosis Introduced internally into the tube wall. Various conventional delivery loaded with NO precursor -The device can be used for in-wall delivery of NO precursors.                             BRIEF DESCRIPTION OF THE FIGURES   1A and 1B show the results of an acute study (FIG. 1A) and a long-term study (FIG. 1B). It is a circuit diagram explaining a processing and an experimental protocol.   FIG. 2A shows endothelium-dependent vasomotion before and after local delivery of L-arginine. You. The Y axis shows the percentage of contraction and expansion, and the X axis shows the course of the experiment. L-arginine administration Previously, there were only minor changes in diameter in both iliac arteries. L-Al After topical delivery of ginine, the treated segments showed significant expansion. Control The rule segment shrank. * = P <0.001. FIG. 2B shows the delivery site. In distant vascular segments, slight changes in vascular diameter relative to acetylcholine Graph showing that only L-arginine delivery had occurred and was not affected by L-arginine delivery It is.   FIG. 3 is a representative aortic photograph of a rabbit with hypercholesterolemia. . Before Ach injection (left panel 10^-FiveM), the iliac artery has the same vessel diameter. Local After drug delivery (right panel), the right iliac artery was identical after receiving L-arginine. Expanded with Ach dose.   FIG. 4 shows the maximal nitric oxide production 1 hour and 1 week after drug delivery It is a graph. Blood vessels (striped bars) after L-arginine treatment are treated with vehicle Shows significantly higher nitric oxide production compared to isolated blood vessels (black bars) (^*p <0.04,^** p <0.01). The absolute value one week after the delivery is L-arginine delivery Significantly higher than that obtained one hour later.   FIG. 5 shows the intima / vehicle ratio bar graph 2 and 4 weeks after topical drug delivery. It is rough. The intima / vehicle ratio is 2 and 4 weeks later compared to vehicle treated vessels L-arginine-treated group was significantly lower (^*p <0.04,^**p <0.01 ).   FIG. 6 shows high catheters 4 weeks after balloon catheter injury and topical drug delivery. 1 shows a low power electron micrograph of the iliac artery of a cholesterolemia rabbit. Intimal thickening Is a vascular segment treated with L-arginine compared to that treated with vehicle (left). Ment (right figure).   FIG. 7 is a bar graph showing the percentage of intimal lesions caused by macrophages. In vascular segments (striped bars) treated with L-arginine, macrophages Accumulation did not exceed 20% of the intimal area. In contrast, vehicle processing In the physical segment, macrophages, in some cases, Up to 70% occurred.   FIG. 8 shows a dilatation balloon in an inflated state and containing a solution of NO precursor In a part of a drug delivery device for use in the present invention located at FIG.   FIG. 9 embodies iontophoresis means for transporting drugs across the balloon surface, FIG. 2 is a fragmentary view of a portion of a NO precursor drug delivery device located within a tube.                          Description of specific embodiments   Treatment of diseases associated with vascular injury, especially associated with angiogenesis and atherectomy And a device for the same. Of particular importance are the blood vessels of vascular smooth muscle cells. Restenosis caused by intimal migration and proliferation and increased atherosclerosis Damage.   A method is provided for introducing NO precursors into the vessel wall at the site of injury, whereby NO production in the cells at the site is enhanced. Infused into the vessel wall and N Various delivery systems that produce NO-forming agents that can be utilized by O-producing cells are used. Can be used. Devices that can be used include drug delivery balloons (eg, (Porous, sonophoretic and iontophoretic balloons) And examples given by the devices shown in WO92 / 11895, WO95 / 05866 and WO96 / 08286 Certified, and also a Dispatch® (Scimed) commercial device is there. Also, Santoian et al., Cath. Cardiov. Diag. (1993) 30: 348-354; Muller J. et al. Am. Coll. Cardiol. (1992) 20: 460-466; and Circulation of Ortiz et al. (199 4) See 89: 1518-1522. NO precursor drug for delivery by catheter Is introduced into the injury site in the delivery balloon. Then the balloon, medicine The agent may be inflated under pressure to be delivered from the balloon to the surrounding vessel wall. use The amount of drug depends on the nature of the drug, the area being treated, and the loss of drug from that area. Can fluctuate. Drug infusion involves cell and extracellular matrix in the area of injury. Exposed to the drug to ensure that these cells enhance NO production. Hold for a time sufficient to be   The medicament may have a single active ingredient or a combination of active ingredients. Is also good. Of particular importance, alone or in combination, as a mixture or as an oligopeptide Amino acids, L-arginine and L-lysine as tides, or biologically equivalent compounds (Eg, a low molecular oligopeptide having about 2 to 10, usually 2 to 6 amino acids) Or acetylated amino acids and oligopeptides).   Use other drugs to enhance nitric oxide production (eg, to enhance absorption). The amount of nitric oxide can be directly enhanced and / or Can enhance the activity of O synthase or protect NO from degradation Can be. Generally, the dosage range will be about 0.2-0.05, the amount being It is administered every time. These compounds include vitamin B₆(5-25mg ), Folate (0.04-1mg), vitamin B₁₂(0.05-0.1 mg), cysteine or N-acetyl Lucysteine (20-100 mg), Vitamin C (25-200 mg), Coenzyme Q (2.5-9 mg ), Glutathione (5 to 25 mg), vitamin E (20 to 100 I.U.), β-carotene (1 to 2500 I. U.), or other physiologically acceptable antioxidants, tocopherols, phenols Compounds, thiols and ubiquinones. These additional additives are Generally, they are present in the formulation in relatively small amounts and generally have about 10% of the nitric oxide precursor. Less than about 5% by weight, more specifically less than about 5% by weight, or even less than about 1% by weight, At least about 0.01% by weight.   It may be deionized water, saline or phosphate buffered saline, etc., usually water A physiologically acceptable medium that is an sexual medium will be used. Active NO precursor The amount of body drug will vary depending on the particular drug used and other additives present. Would. Generally, at least about 50 mg is present, as exemplified by L-arginine Less than about 5 g, usually at least about 100 mg and less than about 2 g, most often At least about 500 mg. Concentrations are generally about 20-500, more usually about 50-500 Can vary widely in the range of 250 g / l.   Processing times are usually at least about 2 minutes, up to about 30 minutes, and generally 5 to 15 minutes. The rate of introduction is generally about 0.05, depending on all other factors. Will be in the range of ５5 ml / min.   The method of the present invention has vascular damage caused by angiogenesis and atherectomy Used for host. The administration time of the NO precursor drug can vary widely, Relatedly, a single dose or a multiple dose in a relatively short time is provided. In general, The treatment can be done before, at the same time as or after the damage, but before Is usually done within about 2 weeks of injury, and not more than about 8 weeks, usually about 6 weeks. Do not exceed, preferably within the range of 0 to 6 weeks (0 is simultaneous with pretreatment or immediately thereafter) , Within 6 hours).   In many cases, patients have narrowed blood vessels, especially hypercholesterolemia, diabetes, He is afflicted with smoking and various conditions related to hypertension. Therefore, usually Handle blood vessels that have been narrowed to varying degrees by platelet deposition on the vessel wall.   The treatment of the NO precursor drug at the same time or almost simultaneously with the damage, before or immediately after the damage, Enhanced vascular NO production and reduced intimal thickening (substantially reducing the potential for restenosis) (Which would reduce it) can be observed.   As shown, various delivery devices are used for activator delivery can do. FIG. 8 shows the inside of an arterial vessel in which the vessel wall is denoted by reference numeral 15. 1 shows a drug delivery device provided with a balloon 12 in an inflated state. Percutaneous transluminal coronary artery dilatation During the tensioning ("PCTA") procedure, the guidewire 10 is inserted at the point after the stenotic lesion. First inserted into the selected artery. Includes catheter body 11 and balloon 12 With a dilatation catheter, then along the guide wire, the balloon site 12 Proceed to the desired location in the arterial system that traverses or crosses the deformity afterwards The balloon 12 passes the NO precursor solution through the balloon lumen 14 to It is expanded by introducing it into the chamber 13. During inflation, the outer surface of balloon 12 Pressure is applied outwardly on the inner surface of the vessel wall 15 to reduce blood vessels in the area of the stenotic lesion. Widens or dilates, so that angiogenesis is performed in this manner and the NO precursor blood Intra-wall introduction into the tube wall is provided.   Porous balloons are made from any of the conventional materials used for that purpose. Can be built. These include acetylcellulose, polyvinyl chloride Nyl, polysulfone, polyacrylonitrile, polyurethane, natural and synthetic elastomers Examples include stomers, polyolefins, polyesters, fluoropolymers, and the like. Normal The thickness of the film is in the range of about 10 ° to 1 μm, and the pore size is about 0.05 to 1 μm. μ.   Alternatively, the drug is delivered to the vessel wall by channels on the outer surface of the balloon. May be used. The balloon is Placed in a diseased vessel segment. The balloon is then replaced by normal means (normal Inflate with a saline solution containing a contrast agent) The flannel (on the surface of the balloon) is brought into contact with the vessel wall. Thereafter, the NO precursor solution is Infuse the channel under pressure. Perforations in the channels cause the solution to Under force, it is ejected into the blood vessel wall, jetted into the wall, Can be strengthened.   Alternatively, an iontophoretic approach may be used. FIG. 9 shows activated NO precursors. Helps guide the body across the balloon wall 26 and into contact with the vessel wall 15 1 shows an iontophoretic structure for performing the above. One electrode 28 and the catheter electrode The other electrode 31, the body surface electrode, is placed on or within the Located on or within the body. The current of the iontophoresis method is controlled by an electric lead (electri cal lead) between electrodes 28 and 31 by external electrode 30 through 29 and 33 respectively. Let it live. DC may be used, but other waveforms may be used (e.g., 100 Hz or A series of short waveforms, producing higher frequencies).   During operation of the iontophoresis device, the balloon 26 is first deployed across the stenotic lesion. Place. The balloon interior 27 was then inflated with the drug in the lumen 23. Ba As the runes expanded, the arteries widened. After this, the power supply is activated Thereby passing a current through the balloon wall 26 between the electrodes 28 and 31. Spawned. This current induces the NO precursor through the wall into chamber 27 And brought into contact with the surrounding vascular wall 15 and vascular tissue.   The following examples are illustrative, not limiting.                                  Example Method animal   Twenty-seven male New Zealand white rats (NZW) weighing 3.8 ± 1.5 kg One week for environmental acclimatization at Stanford department housing facilities After that, they were submitted to the study. All animals are examined by a veterinarian prior to research and a technician And monitored daily by the investigator. Experimental protocol, Stanford Approved by the university laboratory animal care administration panel. American Association for Accreditation of Laboratory Animal Care Performed according to the recommendations of   The animals were then treated for 5 weeks with a high cholesterol diet (1%, Dyets, Bethlehem, PA). Two protocols (acute and long-term studies) were performed as follows : (FIGS. 1A & B) Acute study (n = 13: see FIG. 1A for protocol). Do this research Therefore, local NO synthesis can be enhanced by intramural administration of the NO precursor L-arginine Was measured. Anesthesia and surgical preparation   Six days after the start of the high cholesterol diet, rabbits were treated with ketamine (5 mg / kg). ) And rompun (35 mg / kg). Exposed right carotid artery Gently, make an incision, and examine the tygon sheath (5 French diameter) with a fluoroscope. It was inserted under the control into the descending aorta. Angioplasty balloons (ACS, BA Rune diameter 3 mm) into any iliac artery, 30 seconds between each inflation Then, 6 times, it was inflated with 8 ATM in the far part of the deep femoral artery. After that, The same procedure was repeated in the contralateral iliac artery. After another 4 weeks diet Anesthetize the material and cannulate the left carotid artery for catheterization and local drug delivery. Inserted (cannulate). Topical drug delivery   Topical drug delivery balloon (3mm, Dispatch®, Scimed) It was placed in the left carotid artery and placed at the same site as the previous balloon injury. Delivery catheter The proximal end of the fluoroscopy control for a landmark reference. It was located below the internal iliac branch. Balloon to 6 atm Inflate and add L-arginine (800 mg / 5 ml) or saline at 0.2 ml / min for 15 minutes During the injection. Thereafter, the procedure was repeated in the contralateral iliac artery. Arginine The iliac artery to be treated was determined randomly. Kefzol® Intravenous Bo Russ injection was performed to prevent infection. Establishment of endothelium-dependent vasomotion and quantitative angiography   After local administration of arginine or saline, control angiograms were obtained. So After, acetylcholine (10^-Five,Ten^-6M) containing the two injections (3 french diameter) for 3 minutes at a rate of 0.8 ml / min.  bifurcation). Immediately after each injection, angiography of the iliac artery was performed. all Angiography of an electronic caliper system by two researchers system) was measured blindly. The diameter is the drug data at baseline. Three predetermined sites along the area of delivery and local drug delivery Before and after each administration of acetylcholine. In addition, the vessel diameter Locally delivered L-, measured at a reference site distant from the segment The downstream effect of arginine was confirmed. Compared to the baseline The percentage change in diameter was calculated for each dose and expressed as mean ± SEM. Collecting tissue   30-60 minutes after topical delivery of L-arginine, sacrifice animal and watch iliac artery Deeply separated from adjacent tissues. To adapt to each fluoroscopy dissection Care was taken to collect the exact portion of the artery that had more local delivery. To determine the degree of cell damage caused by the local drug delivery balloon, The delivered segments of three rabbits were subjected to electron microscopy. Nitric oxide measurement   The collected iliac artery tubes were placed in cold saline. Open the blood vessels vertically, Calcium ionophore (1 μmol / L, A23187, Sigma, St. Louis, MO) and L-A Lugi Hanks' buffered saline (HBSS) medium containing nin (100 μl / L, Sigma, St. Louis, MO) (Irvine Scientific) 2 ml (37 ° C.).   At the selected elapsed time (0, 30, 60, 120 minutes), a sample of the medium was flushed with nitric oxide (N O_x) Were collected for measurement and replaced with 2 ml of fresh medium. Incubation After the installation, weigh the segment and_xWith commercially available chemilumines The measurement was performed using a sense device (model 2108, Dasibi). Pipette 100 μl of sample It was injected into a reduction chamber containing elevated acid vanadium (III). In the reduction chamber In the NO_TwoAnd NO_ThreeIs reduced to NO, which then reacts with ozone It is later quantified by a chemiluminescence detector. The signal from the detector is Analyzed by a computerized integrator and recorded as the area within the curve You. NO_Two/ NO_ThreeCalibration curve is linear over the range of 50 pmol to 10 nmol. Was. Long-term study (n = 14; see Figure 1B for protocol)   In this study, a single intramural administration of L-arginine resulted in a sustained increase in NO activity. And the hyperplasia of the myointimal membrane and / or macrophage accumulation can be suppressed. Was measured. One week after the start of the diet, balloon injury of the iliac artery was I went there. Immediately afterwards, L-arginine is placed in the wall of the right or left iliac artery, The dose was administered by the Livery system. Using the same catheter system for physiological saline Was administered to the contralateral iliac artery. L-arginine doses and infusion rates have been determined in acute studies. It was similar to what was done. 1 week after balloon injury and topical drug delivery At 2, 2, or 4 weeks (n = 4, 4, and 6, respectively), endothelium-dependent vasomotor Contrast-evaluated and / or vascularized by histomorphometry, immunohistochemistry, or chemil Collected for luminescence. Morphometry analysis (intimal media ratio)   The collected vessels were fixed in 10% buffered formalin and then embedded in paraffin. Was. Divide the embedded vessels into thin sections and use hematoxylin for light microscopy and histomorphometry. Stained with phosphorus and eosin. Measurements of the intima and medial cross-sectional area are provided by the treatment group. Made by experienced observers who are blind. The histological cross section is 1x Digitized, using an Image Analyst. Was. The following boundaries were highlighted using a trackball: outer elastic membrane Within Elastic membrane, lumen / intimal interface. Then calculate the cross section of each vessel wall layer and / Media ratio was calculated. The medium is defined as the area between the outer and inner elastic membranes, It was defined as the vascular layer between the intimal elastic membrane and the intimal / lumen interface. Immunohistochemistry   Immunohistochemical analysis was performed by fixing with formaldehyde and paraffin as described above. Performed on embedded tissue. Rabbit macrophage antibody (RAM11, Dako Corp., Carpenteria, CA) to identify macrophages. Sections for primary antibody For 1 hour at room temperature with anti-rabbit IgG (biotin conjugate) for 30 minutes. Incubated for 20 minutes with gimpoperoxidase. Peroxidase then Using a dye source (Zymed Laboratories, Inc., South San Francisco, CA) Visualized. Cross-sections of each of the three should be either L-arginine or saline Were immunostained for each vascular segment treated with. Macrophage staining is light Evaluation was performed by two experienced observers using a scanning microscope. As medium and inner membrane Measure the area of defined vessels and the percentage of vessels stained for macrophages Was. Nitric oxide measurement   NO for 4 rabbits_xFor the measurement of the level, a local L-arginine Tissue was collected one week after livery. Chemiluminescence measurements as described above I went to. Data analysis   Data are expressed as mean ± SEM. Vascular reactivity to acetylcholine (vas oreactivity) as a percentage change in diameter compared to the baseline. did. Mean change in all arteries in each treatment group (L-arginine or saline) Was used for comparison. Perform an unpaired t-test to find L-argi For each dose of acetylcholine before and after treatment with either nin or saline And compared the values between the two treatment groups. In addition, two factors of change were analyzed. Thus, differences within and between treatment groups were confirmed. Significant difference, p ≦ 0.05 And NO_xThe difference between the levels is the same as the one in the Bonferroni correction of multiple comparisons. Confirmation was made using the Student's t-test.result Acute study (Fig. 1A) Vascular reactivity   FIG. 2A shows acetyl before and after topical delivery of L-arginine or saline. 4 shows the response of vascular segments to rucholine. Baseline vessel diameters Identical before and after local drug delivery in the iliac artery. Topical drugs There was little change in vessel diameter prior to delivery. This is probably Acetylcholine-induced endothelium-dependent vasodilation, especially after vascular injury, especially high cholesterol Represents the fact that in the case of bloodemia, it is weakened in the regenerated endothelium. L-Arki After local delivery of nin, endothelium-dependent vasodilation was restored. By contrast, No vasodilation was observed after local delivery of the drug. The effect of L-arginine , Localized to segments attached to in-wall delivery. Usually the change in vessel diameter is It was not found at sites distal to local delivery of L-arginine (FIG. 2B). Obedience Therefore, this method uses the local (rather than systemic) effects of L-arginine Was observed. Nitric oxide level   NO_xVessel segments collected with measurements 30-60 minutes after local drug delivery It went in. Arginine-treated vascular segments were 30 minutes, 60 minutes and 120 minutes. A significant increase in nitric oxide levels was shown over a one minute incubation period. Long-term study (Fig. 1B) Vascular reactivity   Vasomotor studies were performed 2 weeks or 4 weeks after topical drug delivery. By vehicle Treated iliac arteries tended to contract blood vessels in response to acetylcholine, Those treated with L-arginine tend to vasodilate, where it was observed The difference did not reach statistical signance (Ach 10^-1M; 2.2 ± 1.3% vs. -4.2 ± 3.8%, L-arginine vs. vehicle, Ach 10^-Five; 7.2 ± 1.0 vs -4.0 ± 7.5) . Inner membrane ratio   FIG. 5 shows the results obtained at 2 and 4 weeks after topical drug delivery. L-Al Guinine significantly increased intimal lesions compared to vehicle controls Was suppressed. This phenomenon is even more evident 4 weeks after topical drug delivery . Immunohistochemistry   FIG. 7 shows the percentage of intimal lesion surface area clearly stained for macrophages. Show. 0% to 10% of intimal area clearly in L-arginine treated segment Infiltrate stained cells, but treated with vehicle In addition, the intima area involved in macrophages was significantly higher in In men- tation, it exceeds 50% of the intimal area. Nitric oxide level   NO was measured on vascular segments from four rabbits. Ex vivo Production of L-arginine one week after delivery of L-arginine It was significantly higher than that of Also, these levels will be 1 hour after delivery It was higher than achieved (FIG. 4).   From the above results, it can be seen that the method and device of the present invention can cause restenosis after vascular injury. It is clear that an alternative treatment is provided which substantially reduces the rawness. The method is Simple, can be done with the means of causing vascular injury, and effective I know that Importantly, this approach allows for L-argini Systemic side effects associated with oral or intravenous administration of Provided. Thus, as a result of the reduced occurrence of restenosis, An extended application has been found for this measure.   All documents and patent applications mentioned in this specification are the respective documents or patent applications. Is included in this specification, as is indicated to be included as a reference. Shall be.   Having fully described the present invention, those skilled in the art will recognize many modifications and variations. It should be apparent that modifications and improvements can be made without departing from the spirit or scope of the invention. There will be.

────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Schwarzcher Sverin             United States California             94025 Menlo Park Cleland             Place 8 (72) Inventor Rim Thai Tea             Singapore Singapore Number             16-43 Gilman Heights Block 1             E (72) Inventor Yeung Allensee             United States California             94010 Hillsborough Sugar Hill             Drive 85

Claims (1)

[Claims] 1. The potential for restenosis from damage caused by angiogenesis or atherectomy   A method of reducing the amount of a nitric oxide precursor in the vicinity of the damaged site.   That the amount of nitric oxide formation in the cells is introduced intramurally in a time and amount that is increased.   The method of comprising, thereby reducing the occurrence of restenosis. 2. The nitric oxide precursor is L-arginine, L-lysine, or L-arginine and L-   Claims: At least one of the oligopeptides comprising at least one of lysine.   The method of claim 1. 3. 2. The method of claim 1, wherein the time is at the time of the injury and within four weeks thereafter.   Method. 4. The method of claim 1, wherein said NO precursor is in an aqueous medium. 5. 2. The method of claim 1, wherein the introduction is via a local delivery catheter.   Method. 6. The potential for restenosis from damage caused by angiogenesis or atherectomy   A method of reducing the amount of L-arginine at the site of injury at or after the injury.   Within 2 weeks, an amount of 20-500 g of increasing amount of nitric oxide formation of cells at the site of injury   / introducing as an aqueous solution at a concentration in the range of / l   The method of reducing the occurrence of restenosis. 7. 7. The method of claim 6, wherein the introduction is via a local delivery catheter.   Law. 8. Porous balloon catheter including balloon having a solution of NO precursor in lumen   Le. 9. 9. The catheter according to claim 8, which is iontophoretic. Ten. External channels or connectors for local delivery of solutions containing NO precursors   9. The catheter of claim 8, including a balloon having a compartment.