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1.
Surg Radiol Anat ; 45(5): 611-622, 2023 May.
Article in English | MEDLINE | ID: mdl-36912942

ABSTRACT

PURPOSE: The tarsal tunnel (TT) is a fibro-osseous anatomical space coursing from the medial ankle to the medial midfoot. This tunnel acts as a passage for both tendinous and neurovascular structures, including the neurovascular bundle containing the posterior tibial artery (PTA), posterior tibial veins (PTVs) and tibial nerve (TN). Tarsal tunnel syndrome (TTS) is the entrapment neuropathy that describes the compression and irritation of the TN within this space. Iatrogenic injury to the PTA plays a significant role in both the onset and exacerbation of TTS symptoms. The current study aims to produce a method to allow clinicians and surgeons to easily and accurately predict the bifurcation of the PTA, to avoid iatrogenic injury during treatment of TTS. METHODS: Fifteen embalmed cadaveric lower limbs were dissected at the medial ankle region to expose the TT. Various measurements regarding the location of the PTA within the TT were recorded and multiple linear regression analysis performed using RStudio. RESULTS: Analysis provided a clear correlation (p < 0.05) between the length of the foot (MH), length of hind-foot (MC) and location of bifurcation of the PTA (MB). Using these measurements, this study developed an equation (MB = 0.3*MH + 0.37*MC - 28.24 mm) to predict the location of bifurcation of the PTA within a 23° arc inferior to the medial malleolus. CONCLUSIONS: This study successfully developed a method whereby clinicians and surgeons can easily and accurately predict the bifurcation of the PTA, to avoid iatrogenic injury that would previously lead to an exacerbation of TTS symptoms.


Subject(s)
Tarsal Tunnel Syndrome , Tibial Arteries , Humans , Tarsal Tunnel Syndrome/etiology , Tarsal Tunnel Syndrome/surgery , Tibial Nerve , Ankle , Iatrogenic Disease/prevention & control
2.
Ir Med J ; 111(7): 788, 2018 08 13.
Article in English | MEDLINE | ID: mdl-30520615

ABSTRACT

Hospital overcrowding is evidenced by Emergency Department (ED) overcrowding. The Full Capacity Protocol (FCP) is activated to move patients to temporary extra beds placed in the inpatient wards. This research aims to establish patient preferences when waiting for a ward bed in an Irish Hospital. The FCP in Beaumont Hospital was updated in the context of national guidelines. Patients' attitudes towards boarding in the ED as opposed to being in extra beds on the wards were assessed using a questionnaire based structured interview. Ninety nine patients took part in the study. Eighty three patients (83.83%) preferred being an additional patient on the ward, 12 (12.12%) had no preference and four (4.04%) preferred being boarded in the ED. Moving patients from the ED into extra beds on the wards creates space, facilitating safer care delivery. The vast majority of patients who have experienced both, prefer being boarded in the ward rather than in the ED.

3.
J Musculoskelet Neuronal Interact ; 14(4): 454-63, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25524971

ABSTRACT

OBJECTIVES: SHARPIN is a subunit of LUBAC and regulates activation of NF-κB, a pivotal transcription factor in skeletal homeostasis. Mutated SHARPIN gene (cpdm) mice develop chronic proliferative dermatitis and systemic inflammation. Cpdm mice have an osteopaenic phenotype characterised by decreased cortical and trabecular bone volume, but whether this is a consequence of the hyper-inflammatory phenotype is unknown. The inflammatory phenotype of cpdm mice is prevented by Tnf deficiency so we examined cpdm.Tnf (-/-) mice to examine the role of SHARPIN in skeletal development. METHODS: This research determined the extent to which SHARPIN and TNF interact within the skeleton through analyses of gene expression, µCT and biomechanical properties of bones of control (CTRL), cpdm, Tnf (-/-) (TNF KO) and cpdm.Tnf (-/-) (cpdm/TNF KO) mice. RESULTS: Gene expression of IL-1ß, TNF and caspase-3 increased in cpdm mice but was comparable to control values in cpdm/TNF KO mice. Decreased cortical and trabecular bone in cpdm mice translated to a loss in bone strength (ultimate stress and peak force). Cpdm/TNF KO mice developed bones similar to, or stronger than, control bones. CONCLUSIONS: Our results suggest that SHARPIN plays a significant role in skeletal homeostasis and that this role is strongly regulated through TNF pathways.


Subject(s)
Bone and Bones/metabolism , Carrier Proteins/metabolism , Homeostasis/physiology , Tumor Necrosis Factor-alpha/metabolism , Animals , Biomechanical Phenomena , Intracellular Signaling Peptides and Proteins , Male , Mice , Mice, Knockout , Reverse Transcriptase Polymerase Chain Reaction , Tensile Strength , X-Ray Microtomography
4.
J Musculoskelet Neuronal Interact ; 14(2): 162-72, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24879020

ABSTRACT

OBJECTIVES: Previous studies have shown galanin (GAL) injections onto mouse calvaria increased bone thickness and osteoblast number. This study investigated the effects of the GAL receptor agonist galnon on bone loss using the ovariectomised (OVX) rat model. METHODS: OVX rats were treated with either vehicle or galnon for 6 weeks via mini-osmotic pumps. Plasma osteocalcin concentrations, osseous cell gene expression, morphological and biomechanical properties of the skeleton were compared between the two groups. RESULTS: Treatment with galnon increased RANKL:OPG gene ratio (p<0.001) plus expression of TNF-α (p<0.05) and cathepsin K (p<0.05). µCT analyses revealed galnon-treated OVX animals had reduced trabecular and cortical morphology compared to control animals. Biomechanically, galnon OVX animals required similar peak force to failure to that of control OVX animals although galnon treatment did enhance the mechanical properties of Young's modulus and ultimate tensile stress. CONCLUSIONS: Our research suggests that galnon, a GAL receptor agonist, may enhance osteoclastic bone resorption in OVX rats. Although galnon reduced bone volume, biomechanical testing revealed that bone of galnon-treated animals was mechanically superior per unit area. Taken together, galnon simultaneously improves the intrinsic quality of cortical bone whilst stimulating osteoclastic activity in the OVX rat model.


Subject(s)
Bone Density Conservation Agents/pharmacology , Bone and Bones/drug effects , Coumarins/pharmacology , Osteoporosis, Postmenopausal , Animals , Biomechanical Phenomena , Disease Models, Animal , Female , Humans , Ovariectomy , Rats , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Receptors, Galanin/agonists , X-Ray Microtomography
5.
Br J Ophthalmol ; 93(9): 1172-6, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19414441

ABSTRACT

AIMS: To report the treatment outcomes and complication rates of stereotactic radiotherapy in the management of patients with juxtapapillary choroidal melanoma. METHODS: A retrospective review of 64 consecutive patients with juxtapapillary choroidal melanoma, located within 2 mm of the optic disc, treated with stereotactic radiotherapy at Princess Margaret Hospital between October 1998 and January 2006. RESULTS: The median age was 63 years. The median tumour height was 4.2 mm, and median largest basal diameter was 9.8 mm. The prescribed radiation dose was 70 Gy in five fractions over 10 days, and the median follow-up was 37 months. Post-treatment, the actuarial rates of local tumour control, metastases and survival at 37 months were 94%, 15% and 90%, respectively. Actuarial rates of radiation-induced complications at 37 months were neovascular glaucoma 42%, cataract 53%, retinopathy 81% and optic neuropathy 64%. Secondary enucleation was necessary for 10 patients (16%), in four patients for tumour recurrence and in six for painful neovascular glaucoma. CONCLUSIONS: Stereotactic radiotherapy offers a non-invasive alternative to enucleation and brachytherapy in the management of juxtapapillary choroidal melanoma with a high tumour control rate, however, at the expense of a significant rate of long-term ocular complications.


Subject(s)
Choroid Neoplasms/surgery , Melanoma/surgery , Neoplasm Recurrence, Local/surgery , Radiosurgery/methods , Choroid Neoplasms/pathology , Dose Fractionation, Radiation , Female , Follow-Up Studies , Humans , Male , Melanoma/pathology , Middle Aged , Neoplasm Recurrence, Local/pathology , Radiosurgery/adverse effects , Retrospective Studies , Treatment Outcome , Visual Acuity/physiology
6.
Eye (Lond) ; 17(3): 364-8, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12724700

ABSTRACT

This paper describes three cases of vasoproliferative tumours of the retina including histopathology in one. The clinical presentation, differential diagnosis and treatment modalities are discussed with a brief review of the literature.


Subject(s)
Hemangioma/diagnosis , Retinal Neoplasms/diagnosis , Aged , Diagnosis, Differential , Female , Hemangioma/pathology , Hemangioma/therapy , Humans , Male , Melanoma/diagnosis , Middle Aged , Retinal Neoplasms/pathology , Retinal Neoplasms/therapy
7.
Br J Fam Plann ; 26(3): 131-5, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10920287

ABSTRACT

This paper describes the development and pilot evaluation of a peer-produced video, produced for use as part of North Staffordshire's Personal and Social Education school programme. A number of studies carried out in the area, including a recent audit into post-coital contraception in the under 20s, have shown that young people need to know how to access contraceptive services. Background surveys also suggest that young people need to be aware of the wider issues implicit in contraception. The impetus for the video came from the Advice Centres for the under Twenties (ACT) Working Party, who produced the video together with Staffordshire University's Media Studies Department and a local high school drama group. The video was intended for use in schools, and was designed to be complimentary to an updated and standardised teaching pack, which was already in preparation. The pilot study showed the video to be beneficial as a stand-alone intervention, principally to promote active discussion on topics that might otherwise be difficult to approach. A comparison of responses before and after the educational session demonstrated an improvement in knowledge in most areas. Further objective evaluation of the combined video and teaching pack is now necessary.


Subject(s)
Contraception/methods , Pregnancy in Adolescence/prevention & control , Sex Education/methods , Adolescent , Contraception/classification , Contraceptive Agents , Female , Humans , Male , Pilot Projects , Pregnancy , Program Evaluation , Surveys and Questionnaires , Video Recording
9.
Am J Ophthalmol ; 123(4): 506-14, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9124247

ABSTRACT

PURPOSE: To correlate ultrasound biomicroscopic features of the anterior aspect of peripheral choroidal melanoma with respect to histopathology. METHODS: We examined 17 eyes of 17 patients who had clinically diagnosed peripheral choroidal melanomas that approached the ora serrata or extended into the ciliary body and who had been assessed with ultrasound biomicroscopy before enucleation. Comparisons were made between anterior tumor margins imaged by ultrasound biomicroscopy and histopathologic specimens. Anatomic features noted on ultrasound biomicroscopy before enucleation were correlated with enucleation specimens, including supraciliary effusion, rotation of the ciliary body, angle involvement, and internal reflectivity patterns. Anterior tumor margin position was determined with reference to the scleral spur. RESULTS: Mean distances from the anterior tumor margin to the scleral spur were 1.47 mm on ultrasound biomicroscopy and 1.65 mm on pathologic examination. This difference was not statistically significant (P = .325). Tumor features evident on ultrasound biomicroscopy were also seen on pathologic examination: supraciliary choroidal effusions in seven of seven, ciliary body rotation in seven of eight, and angle involvement in seven of eight. All tumors were mixed-cell melanomas, and 12 of 17 (70%) demonstrated homogeneous ultrasound biomicroscopic internal reflectivity. Irregular internal reflectivity was seen in five of 17 tumors (29%) and was related to prominent internal vascularity on pathology in three of five. CONCLUSIONS: Ultrasound biomicroscopy is an accurate imaging technique for the in vivo assessment of anterior tumor margins of peripheral choroidal melanomas and can provide detailed imaging of the tumor's interface with the ciliary body.


Subject(s)
Anterior Eye Segment/diagnostic imaging , Choroid Neoplasms/diagnostic imaging , Melanoma/diagnostic imaging , Choroid Neoplasms/pathology , Ciliary Body/diagnostic imaging , Female , Humans , Male , Melanoma/pathology , Microscopy , Middle Aged , Neoplasm Staging , Ultrasonography
10.
Leuk Lymphoma ; 20(1-2): 161-3, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8750639

ABSTRACT

A 56-year-old woman presented with CML in lymphoid blast crisis. Complete remission with no suggestion of CML was achieved with chemotherapy. Twenty-six months later, an isolated ocular anterior chamber relapse of acute leukemia presenting as uveitis (ocular masquerade syndrome) was diagnosed and treated with radiotherapy. Ten months later, a second ocular relapse in the same location was diagnosed and treated with radiotherapy. Two months later, a systemic relapse into second chronic phase was diagnosed and is currently being treated with alpha interferon. Only one previous case of leukemic hypopyon in CML has been reported. This is also the first case of isolated ocular blast crisis relapse in CML to be described.


Subject(s)
Blast Crisis , Eye Neoplasms/pathology , Eye Neoplasms/secondary , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Uveitis/etiology , Cobalt Radioisotopes/therapeutic use , Eye Neoplasms/radiotherapy , Eye Neoplasms/therapy , Female , Humans , Interferon-alpha/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy , Middle Aged , Recurrence , Syndrome
11.
Ophthalmology ; 99(8): 1220-8, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1513574

ABSTRACT

BACKGROUND: Ultrasound biomicroscopy is a new method of imaging the anterior segment of the eye at microscopic resolution using high frequency ultrasound. METHODS: A prospective study was performed to evaluate the use of ultrasound biomicroscopy in imaging anterior segment tumors. Forty-five patients underwent clinical examination followed by slit-lamp photography, anterior segment B-scan ultrasonography, and ultrasound biomicroscopy according to an established protocol. RESULTS: All lesions were clearly imaged by ultrasound biomicroscopy, while only 17 were detectable by conventional B-scan ultrasound. Ultrasound biomicroscopy allowed precise measurement and visualization of subsurface features in small tumors. Differentiation between solid and cystic lesions was easily achieved. The margins of ciliary body tumors could be more accurately defined. Histopathologic correlation was possible in four cases managed surgically. Ultrasound biomicroscopy images compared favorably with low-power microscopy. No complications were encountered. CONCLUSION: Ultrasound biomicroscopy proved a valuable new noninvasive technique in the evaluation of anterior segment tumors.


Subject(s)
Anterior Eye Segment/diagnostic imaging , Eye Neoplasms/diagnostic imaging , Anterior Eye Segment/pathology , Choroid Neoplasms/pathology , Choroid Neoplasms/ultrastructure , Ciliary Body/diagnostic imaging , Ciliary Body/pathology , Cysts/diagnostic imaging , Cysts/pathology , Eye Neoplasms/pathology , Humans , Iris Neoplasms/pathology , Iris Neoplasms/ultrastructure , Prospective Studies , Ultrasonography , Uveal Neoplasms/pathology , Uveal Neoplasms/ultrastructure
12.
Can J Ophthalmol ; 26(6): 328-33, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1751917

ABSTRACT

A 56-year-old man presented with a left ciliary body mass, anterior vitreous hemorrhage and a subluxed, cataractous lens. The clinical course included rapid enlargement of the mass, anterior uveitis, cataract progression and secondary glaucoma. Investigation included fluorescein angiography, ultrasonography and computed tomography. The eye was enucleated because of progressive enlargement with poor vision and uncontrolled secondary glaucoma. Histopathological examination showed an adenoma of the nonpigmented ciliary epithelium with cystic areas of hyaluronidase-sensitive acid mucopolysaccharide. The mass distorted the iris, occluded the angle structures and produced a complete cataract. The basement membrane of the adjacent ciliary processes was extensively thickened. The authors discuss the clinical association with vitreous hemorrhage and the local damage caused by this benign tumour.


Subject(s)
Adenoma/pathology , Ciliary Body/pathology , Pigment Epithelium of Eye/pathology , Uveal Neoplasms/pathology , Adenoma/diagnostic imaging , Cataract/etiology , Ciliary Body/diagnostic imaging , Eye Enucleation , Humans , Lens Subluxation/etiology , Male , Middle Aged , Pigment Epithelium of Eye/diagnostic imaging , Tomography, X-Ray Computed , Ultrasonography , Uveal Neoplasms/complications , Uveal Neoplasms/diagnostic imaging , Vitreous Hemorrhage/etiology
13.
J Hypertens ; 7(11): 891-4, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2607143

ABSTRACT

Reversal of one-kidney, one clip (1-K, 1C) hypertension by removal of the renal artery clip is accompanied by increased renal and vascular prostaglandin (PG) production. It was postulated that PG biosynthesis is stimulated in the unclipped hypertensive kidney. In order to test this hypothesis, we compared urinary excretion of PGE2 and 6-keto-PGF1 alpha (a breakdown product of PGI2) in perfused kidneys isolated from 1-K, 1C hypertensive rats, 1-K, sham-clipped rats and 1-K, 1C rats which had failed to become hypertensive. Urine was collected over 15 min periods at perfusion pressures of 100, 150 and 200 mmHg. At perfusion pressures of 100 and 150 mmHg there was no significant difference in PGE2 excretion between the three groups. In contrast, 6-keto-PGF1 alpha excretion at 150 mmHg was higher in the hypertensive rats compared with the sham-clipped (P less than 0.05) and failed hypertensive (P less than 0.01) rats. At 200 mmHg, both PGE2 and 6-keto-PGF1 alpha were significantly higher in the hypertensive rats than in the control groups. These increases in PG excretion were clearly dissociated from changes in urinary flow rates. The findings support the hypothesis of increased synthesis of renal vasodilatory and natriuretic PGs in 1-K, 1C hypertension which is particularly evident at higher perfusion pressures, such as may be encountered when the hypertensive kidney is unclipped and exposed to high arterial pressure.


Subject(s)
6-Ketoprostaglandin F1 alpha/biosynthesis , Dinoprostone/biosynthesis , Hypertension/metabolism , Kidney/metabolism , 6-Ketoprostaglandin F1 alpha/urine , Animals , Dinoprostone/urine , Male , Rats , Rats, Inbred Strains
14.
Ophthalmology ; 96(4): 538-42, 1989 Apr.
Article in English | MEDLINE | ID: mdl-2726185

ABSTRACT

There is an assumption that radioactive plaques placed at surgery are, and will remain, in proper relationship to the base of the tumor. The plaque dose is calculated based on this assumption. In fact, factors such as loose sutures, improper diameter estimations, pressure from adjacent rectus muscles, and intervening tissue (oblique muscles) can compromise this relationship. Ultrasound provides a practical method of imaging the tumor and plaque simultaneously. The authors have used postoperative ultrasound to monitor the accuracy of iodine-125 plaque placement in nine cases. Detection of eccentrically placed and malpositioned plaques provides valuable insight which can be used to refine surgical technique. Detection of plaque tilting by oblique muscles can serve as a basis for recalculating dosage. The relationship of plaque margins to vital ocular structures such as the optic nerve can also be determined by ultrasound.


Subject(s)
Brachytherapy , Choroid Neoplasms/radiotherapy , Melanoma/radiotherapy , Ultrasonics , Humans , Iodine Radioisotopes
15.
Can J Ophthalmol ; 23(7): 308-10, 1988 Dec.
Article in English | MEDLINE | ID: mdl-3228778

ABSTRACT

Dynamic orbitotonography was done in 17 patients with Graves' disease, 25 patients with orbital tumours and 15 healthy subjects. The mean orbital pressure for both patient groups was significantly different from that for the healthy subjects at each time interval (p less than 0.001). Healthy patients may be differentiated from those with orbital disease with a good degree of reliability with this technique. As well, the technique may provide information about the location of disease within the orbit.


Subject(s)
Eye Diseases/physiopathology , Eye/physiopathology , Adult , Aged , Graves Disease/physiopathology , Humans , Middle Aged , Orbital Neoplasms/physiopathology , Pressure
16.
Am J Physiol ; 255(4 Pt 2): H717-21, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3177664

ABSTRACT

This study examines the effect of dexamethasone (Dex), a phospholipase A2 inhibitor, on the reversal of 1-kidney, 1-clip (1K,1C) hypertension and the synthesis of phospholipase A2-dependent products. Male Sprague-Dawley 1K,1C hypertensive rats [blood pressure (BP) greater than 190 mmHg] were allocated to three groups: two groups were given daily oral doses of Dex (0.142 mg/kg in water) for 72 h, whereas the third group was given water only (controls). One of the Dex-treated groups was then sham unclipped (n = 9), while the other Dex-treated group (n = 8) and the control group (n = 8) were unclipped. Dex attenuated the BP fall in the unclipped (223 +/- 8-148 +/- 9 mmHg) compared with the control unclipped (226 +/- 9-114 +/- 5 mmHg) animals (P less than 0.005). Aortic 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) was reduced in unclipped Dex-treated rats (13.4 +/- 1.2 ng/mg) compared with unclipped control rats (16.3 +/- 1.4 ng/mg; P less than 0.05) but was higher than in the sham-unclipped Dex group (11.5 +/- 1.2 ng/mg; P less than 0.05). Serum thromboxane B2 (TxB2) in the unclipped Dex-treated group was lower than in the unclipped control rats (P less than 0.05) but higher than in sham-unclipped rats (P less than 0.05). Dex significantly increased urinary prostaglandin E2 (PGE2) excretion, whereas urinary 6-keto-PGF1 alpha was unaltered. After unclipping, both urinary PGE2 and 6-keto-PGF1 alpha increased significantly, although there was no obvious difference between Dex-treated and control animals. These findings demonstrate opposite effects of Dex on renal compared with extrarenal prostanoid synthesis and support the hypothesis that attenuation of aortic 6-keto-PGF1 alpha synthesis may be responsible for the smaller fall in BP after unclipping in Dex-treated rats.


Subject(s)
Blood Pressure/drug effects , Dexamethasone/pharmacology , Hypertension, Renovascular/physiopathology , 6-Ketoprostaglandin F1 alpha/urine , Animals , Creatinine/urine , Dinoprostone/urine , Disease Models, Animal , Male , Phospholipases A/antagonists & inhibitors , Phospholipases A2 , Potassium/urine , Rats , Rats, Inbred Strains , Reference Values , Sodium/urine , Thromboxane B2/blood
17.
Clin Sci (Lond) ; 74(4): 393-6, 1988 Apr.
Article in English | MEDLINE | ID: mdl-3356112

ABSTRACT

1. This study analyses whole blood in acutely unclipped one-kidney, one-clip (1K, 1C) hypertensive rats for the presence of platelet-activating factor (PAF), a potent vasodilator and a putative mediator of the rapid blood pressure (BP) fall seen after unclipping. 2. Hypertensive 1K, 1C rats were anaesthetized and a carotid and jugular cannula were inserted for BP measurement and anaesthetic infusion respectively. After a stable level of anaesthesia was attained, the constrictive clip was removed and BP was recorded for 30 min. 3. Blood was drawn from the aorta directly into ice-cold acetone. The extract was analysed for PAF by a bioassay using 5-hydroxy-[14C]tryptamine-labelled platelets. 4. Rats which showed a BP fall had elevated levels of PAF [55 +/- 6 (SEM) pg/ml] (P less than 0.01). 5. This supports the hypothesis that activation of PAF biosynthesis may be a mechanism contributing to the fall in BP seen after unclipping the 1K, 1C hypertensive rat.


Subject(s)
Hypertension, Renovascular/blood , Platelet Activating Factor/analysis , Animals , Blood Pressure , Hypertension, Renovascular/physiopathology , Male , Rats , Rats, Inbred Strains , Time Factors
18.
Am J Physiol ; 251(6 Pt 2): H1361-4, 1986 Dec.
Article in English | MEDLINE | ID: mdl-3538908

ABSTRACT

Previous studies have implicated vasodilatory prostaglandins (PGs) in the reversal of hypertension following unclipping in the one-kidney, one-clip (1K,1C) hypertensive rat. The capacity of the aorta to synthesize prostacyclin (PGI2) was compared in clipped (group A, n = 9), unclipped (group B, n = 8 and group D, n = 9), and sham-unclipped (group C, n = 9) 1K,1C hypertensive rats. The involvement of platelet-activating factor (PAF), a potent renal antihypertensive phospholipid, in the reversal of renal clip hypertension was also examined. Hypertensive rats [systolic blood pressure (BP) greater than 180 mmHg] were fed a synthetic diet for 4 wk, after which group A was killed immediately, group C was sham-unclipped, and groups B and D unclipped and killed 24 h later. Blood was drawn for the measurement of plasma lyso-PAF (the precursor of PAF) and the aorta removed for determination of 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha, the stable hydrolysis product of PGI2). BP fell substantially in the unclipped rats (groups B and D) but did not change in the sham-unclipped rats (group C). Mean aortic 6-keto-PGF1 alpha was increased in the unclipped groups [group B, 15.4 +/- 2.4 (SE) ng/mg; group D, 10.8 +/- 2 ng/mg] compared with group A (7.7 +/- 1 ng/mg) and group C (7.1 +/- 1 ng/mg) (H = 13.74, P less than 0.01). Plasma lyso-PAF was also significantly increased in the unclipped (group D, 261 +/- 26 ng/ml) vs. the sham-unclipped group (group C, 211 +/- 23 ng/ml, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Aorta/metabolism , Epoprostenol/biosynthesis , Hypertension, Renovascular/metabolism , Platelet Activating Factor/analogs & derivatives , 6-Ketoprostaglandin F1 alpha/biosynthesis , Animals , Blood Pressure , Hypertension, Renovascular/physiopathology , Male , Platelet Activating Factor/blood , Rats , Rats, Inbred Strains
19.
Hypertension ; 7(6 Pt 1): 886-92, 1985.
Article in English | MEDLINE | ID: mdl-3908314

ABSTRACT

This study was designed to examine the effects of diets that alter prostaglandin biosynthesis on the blood pressure in one-kidney, one clip rats with established hypertension and to compare the prostanoid generating capacity of hypertensive animals with those that remained normotensive. Rats attaining blood pressures of at least 180 mm Hg within 8 weeks of nephrectomy and renal artery stenosis were paired by weight and blood pressure and then placed on either a safflower oil or a prostaglandin I2 inhibitory diet (cod liver oil-linseed oil mix) for 4 weeks. Animals with blood pressures of less than 150 mm Hg were also paired for the same two dietary regimens. Comparison between the two blood pressure groups revealed that on both dietary regimens hypertensive rats produced significantly more aortic 6-keto-prostaglandin F1 alpha and serum thromboxane B2. Rats on the cod liver oil-linseed oil diet incorporated eicosapentaenoic acid into tissue stores with a corresponding decrease in arachidonic acid and significantly impaired ability to generate serum thromboxane B2 (36%), aortic 6-keto-prostaglandin F1 alpha (65%), renal homogenate 6-keto-prostaglandin F1 alpha (64%) and prostaglandin E2 (58%), and urinary prostaglandin E2 (70%) and 6-keto-prostaglandin F1 alpha (52%). Despite these differences in prostanoid synthesizing capacity, no differences in blood pressure were observed between the safflower oil-fed rats and rats fed cod liver oil-linseed oil within either the hypertensive or normotensive groups. These results suggest that prostanoids do not play a major role in maintaining blood pressure in established one-kidney, one clip hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Dietary Fats/administration & dosage , Hypertension, Renovascular/metabolism , Prostaglandins/biosynthesis , 6-Ketoprostaglandin F1 alpha/biosynthesis , Animals , Cod Liver Oil/administration & dosage , Dinoprostone , Linseed Oil/administration & dosage , Male , Prostaglandins E/biosynthesis , Rats , Safflower Oil/administration & dosage , Thromboxane B2/biosynthesis
20.
Am J Physiol ; 249(4 Pt 2): F542-5, 1985 Oct.
Article in English | MEDLINE | ID: mdl-3863493

ABSTRACT

The contribution of the renal nerves in maintaining blood pressure and modulating renal prostanoid synthesis was examined in established (less than 8 wk in duration) one-kidney, one-clip (1K,1C) hypertension in the rat. Systolic blood pressure was measured for 7 days after renal denervation, at which time the renal artery clip was removed. Twenty-four-hour urinary excretion of PGE2 and 6-keto-PGF1 alpha (stable degradation product of PGI2) was determined before and after denervation and unclipping. Compared with sham-denervated rats, denervation (n = 15) resulted in a small but significant fall in blood pressure (from 216 +/- 4 to 182 +/- 4 mmHg after 48 h) and an increase in urinary 6-keto-PGF1 alpha (from 31 +/- 4 to 43 +/- 5 ng/24 h after 24 h). There was no change in PGE2 excretion. Seven days after surgery, blood pressures were similar in denervated (202 +/- 4 mmHg) and sham-denervated (211 +/- 5 mmHg) rats and fell to a similar extent 24 h after unclipping (142 +/- 3 and 147 +/- 4 mmHg, respectively). Urinary 6-keto-PGF1 alpha increased from 25 +/- 5 to 74 +/- 11 in denervated and 21 +/- 2 to 72 +/- 9 ng/24 h in sham-denervated rats in the 24 h after unclipping. PGE2 excretion increased approximately twofold over this period. These findings indicate that the renal nerves have only a minor role in established hypertension in the 1K,1C rat and that the reversal of hypertension and stimulation of renal prostanoid synthesis following unclipping is not dependent on neural mechanisms.


Subject(s)
6-Ketoprostaglandin F1 alpha/urine , Hypertension, Renovascular/metabolism , Kidney/innervation , Prostaglandins E/urine , Animals , Blood Pressure , Denervation , Dinoprostone , Kidney/metabolism , Male , Rats , Rats, Inbred Strains , Time Factors
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