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1.
Interv Neuroradiol ; 19(1): 78-82, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23472728

ABSTRACT

We describe a rare case with a cavernous sinus (CS) dural arteriovenous fistula (DAVF) in which the clinical symptoms disappeared after the patient underwent reopening of an occluded inferior petrosal sinus (IPS). A 66-year-old woman presented with increased intraocular pressure, chemosis, and proptosis on the left side. Angiography demonstrated a left CS DAVF supplied by the dural branches of bilateral internal carotid arteries. The shunt flow was directed to the superior and inferior ophthalmic veins, while the bilateral IPSs were not opacified. Accordingly, a transvenous embolization of the fistula was attempted. Although the microcatheter was navigated to the cavernous sinus through the occluded left IPS, obliteration of the fistula was unsuccessful because of the failure of superselective catheterization at the fistulous point. However, the final image demonstrated the development of an antegrade shunt flow through the left IPS to the internal jugular vein and disappearance of the retrograde reflux to the superior and inferior ophthalmic veins. The patient's clinical symptoms immediately resolved after the operation, and the symptoms have not recurred during a one-year follow-up period. Inappropriate transvenous embolization of CS DAVFs can result in vascular complications arising from the unintentional redistribution of shunt flow. The present case illustrates that the disappearance of retrograde shunt flow to the ophthalmic veins after reopening of the occluded IPS may be sufficient if a superselective approach fails or is anticipated to result only in an incomplete embolization of the fistulous point.


Subject(s)
Cavernous Sinus/diagnostic imaging , Central Nervous System Vascular Malformations/diagnostic imaging , Central Nervous System Vascular Malformations/therapy , Embolization, Therapeutic , Aged , Cerebral Angiography , Female , Humans , Treatment Outcome
2.
Acta Neurochir (Wien) ; 150(7): 637-45, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18548192

ABSTRACT

BACKGROUND: Petroclival meningiomas are vaguely defined as tumours arising from the antero-medial zone to the internal auditory meatus. This report subclassifies petroclival meningiomas based on their origin determined by using radiological and intra-operative findings. METHOD: Ninety-one patients with petroclival meningioma underwent surgery via the anterior transpetrosal approach. The Meckel's cave was routinely opened. Tumour origin was classified into four subtypes according to the main attachment and trigeminal nerve deviation into, upper clivus (UC), cavernous sinus (CS), tentorium (TE), and petrous apex (PA). Their characteristic clinical symptoms and anatomical features were investigated. FINDINGS: The characteristic symptom was ataxia in the UC type (37.5%), abducens nerve palsy in the CS type (64.3%) and trigeminal neuropathy, mainly neuralgia in the PA type (80.0%) with a higher statistical difference from other subtypes. The rate of tumour invasion into Meckel's cave reached 70.3% in average, with the lowest rate in the PA type (25.0%). The rate of middle fossa extension was the highest in the TE type (59.5%). The middle fossa approach was considered to be ideal for UC and TE types because of easier access to the Meckel's cave. Radical dissection without complications was difficult in the CS type. Both the anterior transpetrosal approach and the lateral suboccipital approach could be indicated in the PA type due to the rare invasion of Meckel's cave and middle fossa, and frequent extension into the internal auditory meatus. CONCLUSIONS: This classification is useful to predict the relation between the tumour and the cranial nerves based on symptoms and images. The anterior transpetrosal approach could be used for all four subtypes and with an absolute indication in the UC and TE types showing middle fossa extension.


Subject(s)
Meningeal Neoplasms/classification , Meningeal Neoplasms/surgery , Meningioma/classification , Meningioma/surgery , Neurosurgical Procedures/methods , Abducens Nerve Diseases/etiology , Adult , Aged , Ataxia/etiology , Cavernous Sinus/pathology , Cranial Fossa, Middle , Cranial Fossa, Posterior , Dura Mater/pathology , Female , Humans , Magnetic Resonance Imaging , Male , Meningeal Neoplasms/complications , Meningeal Neoplasms/diagnosis , Meningioma/complications , Meningioma/diagnosis , Middle Aged , Neoplasm Invasiveness , Petrous Bone , Trigeminal Neuralgia/etiology
3.
Acta Neurochir (Wien) ; 150(3): 257-63; discussion 263, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18213442

ABSTRACT

We reviewed 36 patients with endodermal cysts occurring at the craniocervical junction. They were aged between 3 and 66 years. Headache, motor weakness, and neck pain were commonly observed symptoms. Radiographically, T1-weighted magnetic resonance imaging of the tumours demonstrated a hypointense, isointense, or hyperintense signal according to the cystic content. In most cases, the cyst walls did not enhance after gadolinium administration. Histologically, the cysts were found to be lined by a single layer of epithelium. Histochemical and immunohistochemical studies showed that almost all were reactive to periodic acid schiff stain, epithelial membrane antigen, and carcino-embryonic antigen, but negative to glial fibrillary acidic protein. Mainly, the suboccipital approach with or without a laminectomy, or the trans-oral approach were selected for surgical excision of these tumours. In 17 of the 36 patients, total or gross total resections were performed, and subtotal resections were achieved in sixteen. Three patients developed recurrences.


Subject(s)
Central Nervous System Cysts/pathology , Neurosurgical Procedures/methods , Skull Base Neoplasms/pathology , Spinal Neoplasms/pathology , Adult , Aged , Axis, Cervical Vertebra/pathology , Axis, Cervical Vertebra/surgery , Central Nervous System Cysts/physiopathology , Central Nervous System Cysts/surgery , Cervical Atlas/pathology , Cervical Atlas/surgery , Child, Preschool , Cranial Fossa, Posterior/pathology , Cranial Fossa, Posterior/surgery , Decompression, Surgical/methods , Endoderm/pathology , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Neurosurgical Procedures/standards , Occipital Bone/pathology , Occipital Bone/surgery , Skull Base Neoplasms/physiopathology , Skull Base Neoplasms/surgery , Spinal Canal/pathology , Spinal Canal/surgery , Spinal Cord Compression/etiology , Spinal Cord Compression/pathology , Spinal Cord Compression/physiopathology , Spinal Neoplasms/physiopathology , Spinal Neoplasms/surgery , Treatment Outcome
4.
Nuklearmedizin ; 46(3): 101-6, 2007.
Article in English | MEDLINE | ID: mdl-17549321

ABSTRACT

UNLABELLED: The AIM of this study was to evaluate the effect of scatter and attenuation correction in region of interest (ROI) analysis of brain perfusion single-photon emission tomography (SPECT), and to assess the influence of selecting the reference area on the calculation of lesion-to-reference count ratios. PATIENTS, METHODS: Data were collected from a brain phantom and ten patients with unilateral internal carotid artery stenosis. A simultaneous emission and transmission scan was performed after injecting 123I-iodoamphetamine. We reconstructed three SPECT images from common projection data: with scatter correction and nonuniform attenuation correction, with scatter correction and uniform attenuation correction, and with uniform attenuation correction applied to data without scatter correction. Regional count ratios were calculated by using four different reference areas (contralateral intact side, ipsilateral cerebellum, whole brain and hemisphere). RESULTS: Scatter correction improved the accuracy of measuring the count ratios in the phantom experiment. It also yielded marked difference in the count ratio in the clinical study when using the cerebellum, whole brain or hemisphere as the reference. Difference between nonuniform and uniform attenuation correction was not significant in the phantom and clinical studies except when the cerebellar reference was used. Calculation of the lesion-to-normal count ratios referring the same site in the contralateral hemisphere was not dependent on the use of scatter correction or transmission scan-based attenuation correction. CONCLUSION: Scatter correction was indispensable for accurate measurement in most of the ROI analyses. Nonuniform attenuation correction is not necessary when using the reference area other than the cerebellum.


Subject(s)
Brain/anatomy & histology , Brain/diagnostic imaging , Cerebrovascular Circulation , Cerebrovascular Disorders/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Aged , Cerebellum/anatomy & histology , Cerebellum/diagnostic imaging , Female , Functional Laterality , Humans , Male , Middle Aged , Phantoms, Imaging
5.
Interv Neuroradiol ; 7(2): 127-30, 2001 Jun 30.
Article in English | MEDLINE | ID: mdl-20663338

ABSTRACT

SUMMARY: Anticoagulant therapy is usually used after endovascular operations like coil embolization of aneurysms, or for thromboembolic diseases such as myocardial infarction. Few data exist regarding hemorrhage from benign brain tumors during systemic heparinization with the exception of pituitary adenomas (1,2). We experienced two cases of hemorrhage from benign brain tumors during systemic heparinization. The first patient had an unruptured aneurysm in her suprasellar tumor. She underwent coil embolization to prevent hemorrhage during the subsequent tumorectomy. During and after the endovascular operation, she was heparinized and she suffered a hemorrhage from the tumor on the first postoperative day. The second patient had a suprasellar tumor and was heparinized prophylactically for myocardial infarction. He had an intratumoral hemorrhage on the fifth day after the start of the heparinization. This small series suggests that systemic heparinization with brain tumors, even when they are benign, is very dangerous, and further studies with a larger patient base are warranted.

6.
Neuropathology ; 20(1): 56-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10935438

ABSTRACT

The first case of a ventricular meningioma that was encapsulated by the dura-like membrane is reported. Magnetic resonance imaging (MRI) showed a heterogeneous mass with a low intensity rim in the trigone of the right lateral ventricle of a 63-year-old male. Histological examination revealed that the tumor was a transitional meningioma encapsulated by a thick dura-like membrane. Moreover, abundant clusters of the dura-like connective tissue existed in the tumor, indicating that both the dura-like capsule and the dura-like clusters in the tumor were created by the tumor cells.


Subject(s)
Dura Mater/pathology , Lateral Ventricles/pathology , Meningeal Neoplasms/pathology , Meningioma/pathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged
7.
Clin Neurol Neurosurg ; 102(2): 65-71, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10817891

ABSTRACT

Long-term outcome of 17 patients who harbored a large or giant aneurysm of posterior fossa was summarized. The anatomical distribution of aneurysms included eight cases of basilar artery (BA) bifurcation aneurysms, three cases of BA trunk aneurysms, and six cases of vertebral artery (VA) aneurysms. Eight patients received surgical or endovascular treatment for their lesion. The clinical outcome was good recovery in six, moderate disability in one, and vegetative state in one case, respectively. The other nine patients were followed conservatively. Four of them had fatal aneurysmal rupture, and another two patients suffered from aggravation of pre-existing symptoms related to their aneurysm. Only three patients remain intact. Comparison of the radiographic parameters between those who bled and those who did not bleed revealed that those with subsequent rupture had significantly higher rate of aneurysmal thrombus and had a trend for larger diameter of the aneurysm. Although more aggressive and multidisciplinary measure should be taken to these patients to improve their long-term outcome, our results showed the limitation of treatment for these patients in the present era at the same time. The patients with broad neck BA bifurcation aneurysm in which efferent vessels were incorporated into aneurysmal dome, and those with fusiform, giant BA trunk aneurysm with thrombus were the least amenable to treatment in our series.


Subject(s)
Intracranial Aneurysm/surgery , Vertebral Artery/surgery , Adult , Aged , Cerebral Angiography , Cranial Fossa, Posterior , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnosis , Intracranial Aneurysm/mortality , Magnetic Resonance Imaging , Male , Middle Aged , Retrospective Studies , Survival Rate , Vertebral Artery/diagnostic imaging , Vertebral Artery/pathology
8.
Skull Base Surg ; 10(2): 101-5, 2000.
Article in English | MEDLINE | ID: mdl-17171110

ABSTRACT

What is believed to be the first case of a glomus jugulare tumor presenting with intracerebellar hemorrhage is described. A 25-year-old normotensive man suddenly suffered from severe headache, nausea, vomiting, vertigo, and ataxia due to an intracerebellar hemorrhage. Magnetic resonance imaging and angiography revealed a highly vascular jugulare foramen tumor extending into the intracranial space adjacent to the hematoma. Total removal of the tumor was performed successfully via the combined pre- and retrosigmoid approach, and the histologic diagnosis was a glomus jugulare tumor. We concluded that one of the numerous draining veins on the surface of intracranial tumor, which were observed during the operation, was the origin of the intracerebellar hemorrhage.

9.
No To Shinkei ; 51(3): 253-7, 1999 Mar.
Article in Japanese | MEDLINE | ID: mdl-10226290

ABSTRACT

A case of enlarged infundibular dilatation diagnosed by vertebral angiograms with carotid compression was reported. A 57-year-old woman suffered from headache. She underwent MRA which revealed left internal carotid artery aneurysm. Left common carotid angiograms suggested a left saccular internal carotid artery aneurysm (4 mm x 6 mm) without a posterior communicating artery. However, it was confirmed to be an enlarged infundibular dilatation on left vertebral angiograms with carotid compression. It was confirmed at operation microscopically and neuroendoscopically, and the dilatation was treated by coating. When carotid angiograms reveal no posterior communicating artery, it is difficult to differentiate the origin of posterior communicating artery from internal carotid artery-posterior communicating artery junction aneurysms. Vertebral angiograms with carotid compression is useful for the differentiation for the exact diagnosis.


Subject(s)
Aneurysm/diagnosis , Carotid Artery Diseases/diagnosis , Nerve Compression Syndromes/diagnosis , Vertebral Artery/diagnostic imaging , Arcuate Nucleus of Hypothalamus/pathology , Carotid Artery, Internal , Diagnosis, Differential , Dilatation, Pathologic/diagnosis , Endoscopy , Female , Humans , Middle Aged , Radiography
10.
Neurol Med Chir (Tokyo) ; 37(11): 852-5, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9414930

ABSTRACT

A 69-year-old female presented with a meningioma of the pineal region manifesting as gait disturbance and mental dysfunction. Magnetic resonance imaging revealed a homogeneously well-enhanced circumscribed round mass of about 5 cm in diameter in the pineal region. Angiography demonstrated that the tumor was fed mainly by the bilateral middle meningeal arteries (MMAs), and preoperative intravascular embolization was performed through the bilateral MMAs using estrogen-alcohol and polyvinyl acetate. The tumor was very soft and easily totally resected via the right occipital transtentorial approach. Preoperative embolization is a very useful technique to facilitate removal of deep-seated tumors.


Subject(s)
Brain Neoplasms/therapy , Embolization, Therapeutic , Meningioma/therapy , Pineal Gland , Aged , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Female , Humans , Meningioma/diagnostic imaging , Meningioma/surgery , Polyvinyls/therapeutic use , Radiography
11.
Rinsho Shinkeigaku ; 36(11): 1234-9, 1996 Nov.
Article in Japanese | MEDLINE | ID: mdl-9046855

ABSTRACT

A 45-year-old man was admitted to our hospital because of generalized seizure. He had epilepsy and mental retardation since age of two. On admission temperature was 37.9 degrees C but, nuchal rigidity and Kernig's sign were not present. There were no other abnormal findings on physical examination. Neurological examination revealed consciousness disturbance, generalized seizure and mental retardation. Right hemiparesis gradually developed after generalized seizure. Laboratory data did not show any abnormalites to induce cerebral venous thrombosis. A brain MRI revealed hyperintensity on T2-weighted images and slightly enhanced on T1-weighted images in the left frontal lobe, using Gd-DTPA. An increased signal was also noted in the superior sagittal sinus on T1-weighted images. The superior sagittal sinus was patent but the cortical vein in the left frontal lobe was not demonstrated on cerebral angiography. A diagnosis of an isolated cortical vein thrombosis was made by exploratory craniotomy. Anticoagulation with heparin was started. Although the cortical vein thrombosis usually co-exsists with dural sinus thrombosis, an isolated cortical vein thrombosis like this case was rather rare. A case with cerebral venous thrombosis localized only in the left frontal cortical vein is reported, but definitive etiology is not known.


Subject(s)
Cerebral Cortex/blood supply , Cerebral Veins , Intracranial Embolism and Thrombosis/diagnosis , Humans , Male , Middle Aged
12.
No Shinkei Geka ; 20(9): 931-6, 1992 Sep.
Article in Japanese | MEDLINE | ID: mdl-1407357

ABSTRACT

It is generally accepted that the most suitable treatment of AVM is surgical removal which does not cause neurological deficits. But in some cases, it is impossible to treat surgically because of size or location, so the patient is unfortunately discharged with some part of the nidus remaining. In this paper, we report the natural history of residual AVMs in which part of the nidus remained after initial therapy, and try to ascertain whether therapeutic reduction of the nidus is more effective in preventing intracranial hemorrhage than conservative treatment. Of 362 cases, residual AVMs were found in 35 cases, and were followed up for 9.2 years on average. Eighty cases treated with only conservative therapy were also followed up for 10.9 years on average. The annual risk of intracranial hemorrhage for residual AVMs was 2.9% and that for conservatively treated AVMs was 3.0%, not a significant difference. There was no difference between the two groups in mortality or ADL. We conclude that therapeutic reduction of the nidus was not effective in preventing intracranial hemorrhage.


Subject(s)
Intracranial Arteriovenous Malformations/surgery , Adolescent , Adult , Cerebral Hemorrhage/etiology , Cerebral Hemorrhage/prevention & control , Child, Preschool , Female , Follow-Up Studies , Humans , Intracranial Arteriovenous Malformations/complications , Intracranial Arteriovenous Malformations/therapy , Ligation , Male , Prognosis
13.
Jpn J Pharmacol ; 55(4): 513-22, 1991 Apr.
Article in English | MEDLINE | ID: mdl-1679464

ABSTRACT

Sensitivity (pD2 value, negative logarithm of the molar concentration producing the half maximum response) and affinity (pKA value, negative logarithm of dissociation constant) of norepinephrine were determined in 6 arteries from rabbits. A positive correlation was found in the pD2 and pKA values of norepinephrine. The slope was not significantly different from 1. The pD2 and pKP (a negative logarithm of dissociation constant of a partial agonist) values of tizanidine, an alpha 1-partial agonist, were also determined. There were positive correlations between the pD2 and pKP values of tizanidine and also between the two pD2 values of norepinephrine and tizanidine. The slopes were not significantly different from 1. These results suggest that the regional differences in pD2 values of norepinephrine and tizanidine in the arteries are partly due to the affinity and suggest that both drugs interact with one recognition site in the alpha 1-adrenoceptors. The dissociation constants, KD values, and the maximum binding sites, Bmax, for [125I]-HEAT were also estimated by Scatchard analysis of the specific binding of [125I]-HEAT to the membrane fractions from rabbit arteries. The KD values for [125I]-HEAT were also identical. However, Bmax varied considerably among rabbit arteries. There was a positive correlation between the logarithm of Bmax and the pD2 values for norepinephrine. The present results suggest that the regional difference in the pD2 values for norepinephrine in rabbit arteries is due to variations in the affinities to the alpha 1-adrenoceptors as well as the receptor densities.


Subject(s)
Adrenergic alpha-Agonists/pharmacology , Muscle, Smooth, Vascular/drug effects , Receptors, Adrenergic, alpha/drug effects , Tetralones , Adrenergic alpha-Antagonists/pharmacology , Animals , Aorta, Thoracic/drug effects , Arteries/drug effects , Binding, Competitive/drug effects , In Vitro Techniques , Iodine Radioisotopes , Kinetics , Male , Muscle Contraction/drug effects , Norepinephrine/pharmacology , Phenethylamines/pharmacology , Rabbits
14.
Gen Pharmacol ; 22(1): 77-82, 1991.
Article in English | MEDLINE | ID: mdl-2050290

ABSTRACT

1. The potency (pD2 value) of phenylephrine increased with age from 3 to 10 weeks, but decreased thereafter from 10 to 80 weeks, while the affinity (pKA value) of phenylephrine to alpha 1-adrenoceptors did not alter with aging. 2. The potency (pD2 value) of serotonin did not alter with aging. 3. There is no significant difference between slopes of regression lines between a cytosolic free Ca2+ level ([Ca2+]i) and tension in the presence of phenylephrine in aorta strips from 10- and 60-week-old rats, suggesting that the sensitivity of contractile system to Ca2+ did not alter with aging. 4. Effect of ryanodine on the transient increase of [Ca2+]i and the followed sustained contraction induced by phenylephrine or serotonin in Ca2+ free solution did not alter with aging.


Subject(s)
Aging/physiology , Muscle, Smooth, Vascular/drug effects , Phenylephrine/pharmacology , Serotonin/pharmacology , Aging/drug effects , Animals , Aorta, Thoracic/drug effects , Caffeine/pharmacology , Calcium/metabolism , Fura-2 , In Vitro Techniques , Isometric Contraction/drug effects , Male , Muscle Contraction/drug effects , Potassium/pharmacology , Rats , Rats, Inbred Strains , Ryanodine/pharmacology
15.
Can J Physiol Pharmacol ; 68(10): 1329-33, 1990 Oct.
Article in English | MEDLINE | ID: mdl-1981855

ABSTRACT

Fura 2 loaded thoracic aorta strips from rabbits were used. Norepinephrine, phenylephrine, clonidine, and tizanidine induced an increase in cytosolic Ca2+ concentration [( Ca2+]i) and muscle tension in a concentration-dependent manner. A positive correlation between [Ca2+]i and tension development owing to the agonists was noted. The slope of regression lines between [Ca2+]i and tension development for clonidine and tizanidine, alpha 1-adrenergic partial agonists, were significantly steeper than those for norepinephrine and phenylphrine, alpha 1-adrenergic full agonists. The intrinsic activities of the partial agonists obtained from tension development were greater than those from changes in [Ca2+]i. These results suggest that the partial agonists cause a greater muscle tension than the full agonists at the same level of [Ca2+]i.


Subject(s)
Adrenergic alpha-Agonists/pharmacology , Aorta, Thoracic/drug effects , Calcium/metabolism , Cytosol/metabolism , Muscle Contraction/drug effects , Muscle, Smooth, Vascular/drug effects , Animals , Aorta, Thoracic/metabolism , Aorta, Thoracic/physiology , Dose-Response Relationship, Drug , Kinetics , Male , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/physiology , Norepinephrine/pharmacology , Phenoxybenzamine/pharmacology , Phenylephrine/pharmacology , Potassium/pharmacology , Rabbits
16.
J Pharmacobiodyn ; 12(12): 781-6, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2635736

ABSTRACT

Fura 2-loaded thoracic aorta strips from rabbits were used. Norepinephrine and clonidine induced an increase in cytosolic Ca2+ concentration ([Ca2+]i) and in muscle tension in a concentration-dependent manner. A positive correlation between [Ca2+]i and tension development due to norepinephrine and clonidine was noted in muscle strips both untreated and treated with phenoxybenzamine (PBZ). As the total receptor population was reduced by the PBZ treatment, norepinephrine acted as a partial agonist in the treated strips. The slope of a regression line for norepinephrine in the untreated muscle strips was significantly smaller than the slopes for the same drug in PBZ-treated strips and for clonidine, suggesting that norepinephrine in the PBZ-treated strips and clonidine induced a greater tension at same [Ca2+]i than did norepinephrine in the untreated strips.


Subject(s)
Calcium/metabolism , Clonidine/pharmacology , Cytosol/metabolism , Norepinephrine/pharmacology , Animals , Dose-Response Relationship, Drug , Male , Muscle Contraction/drug effects , Muscle, Smooth, Vascular/physiology , Rabbits , Receptors, Adrenergic/physiology
17.
Neurol Med Chir (Tokyo) ; 29(7): 606-9, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2477761

ABSTRACT

A nonfamilial case of Turcot syndrome (glioma-polyposis syndrome) is described. A 16-year-old male with no siblings first developed a frontal astrocytoma, and was later found to have colonic polyposis with adenocarcinoma. The family history was negative for the syndrome, but his parents were first cousins.


Subject(s)
Adenocarcinoma/complications , Astrocytoma/complications , Brain Neoplasms/complications , Colonic Neoplasms/complications , Intestinal Polyps/complications , Adenocarcinoma/pathology , Adenocarcinoma/surgery , Adolescent , Astrocytoma/pathology , Astrocytoma/surgery , Brain Neoplasms/pathology , Brain Neoplasms/surgery , Colonic Neoplasms/pathology , Colonic Neoplasms/surgery , Humans , Intestinal Polyps/pathology , Intestinal Polyps/surgery , Male , Syndrome
18.
Arch Int Pharmacodyn Ther ; 294: 175-84, 1988.
Article in English | MEDLINE | ID: mdl-2852929

ABSTRACT

Noradrenaline sensitivity (pD2-value) and agonist dissociation constant (pKA-value) were determined in the following 4 canine arteries: thoracic and abdominal aorta, mesenteric and renal. The experiments were done in the presence of beta- and alpha 2-adrenoceptor blockers, and inhibitors of neuronal and non-neuronal uptake of catecholamine. A positive correlation was found in the pD2- and pKA-values for noradrenaline (r = 0.976, P less than 0.05). The slope (0.92) was not significantly different from 1. The pD2- and pKp (negative log of dissociation constant of partial agonist)-values of clonidine, an alpha 1-adrenergic partial agonist, were also determined. There was a positive correlation between the pD2- and pKp-values (r = 0.974, P less than 0.05). Again, the slope (1.39) was not significantly different from 1. These results indicate that the regional difference in the pD2-values for noradrenaline and clonidine in canine arteries is due to the affinities to alpha 1-adrenoceptors and that there is a qualitative difference between alpha 1-adrenoceptor mechanisms in the arteries and veins. However, no positive correlation between the pD2-values for noradrenaline and clonidine was observed (r = 0.182, P greater than 0.05). Thus, it may be suggested that either the recognition sites for noradrenaline, clonidine and prazosin are different or else their mode of attachment to the same recognition site is not identical.


Subject(s)
Muscle, Smooth, Vascular/drug effects , Receptors, Adrenergic, alpha/drug effects , Animals , Clonidine/pharmacology , Dogs , Female , In Vitro Techniques , Male , Norepinephrine/pharmacology , Phenoxybenzamine/pharmacology , Prazosin/pharmacology
20.
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