Protective effect of a fish egg homogenate marine compound on arterial ultrastructure in spontaneous hypertensive rats.

We assessed the effect of a sturgeon eggs-based nutraceutical (LD-1227) versus eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) on the ultrastructure of spontaneously hypertensive rat (SHR) aortas. Sixty SHR were randomly divided into three groups that were fed (1) rat chow, (2) rat chow plus 10 mg of EPA/DHA, or (3) rat chow plus 10 mg of LD-1227, for 18 weeks. Afterward, aortas of these rats were used for blind measurements of the thickened intima area and examination by electron microscopy. Control SHR showed an expanded subendothelial space and leukocyte infiltration of the intima that were reduced in LD-1227-fed rats (p<0.05) and less in EPA/DHA group. Transmission electron microscopy showed endothelial alteration with severe subcellular injury and, unlike the EPA/DHA-group, LD-1227-treated rats displayed a significant reduction in endothelial alteration with severe subcellular injury (p<0.05). These data suggest that LD-1227 has stronger arterial protective properties and deserves further investigation in view of a preventive medicine strategy.

[Vascular morphological and microdensity changes of corneal neovascularization induced by topical bevacizumab and sunitinib in an animal model]. / Cambios en la morfología y la microdensidad neovascular corneal inducidos tras la administración tópica de bevacizumab y sunitinib en un modelo animal.

OBJECTIVE: To evaluate the effects of topical bevacizumab and topical sunitinib on vascular microdensity and morphology of corneal neovascularization (NV). METHODS: A total of 33 rabbits were distributed into 3 groups: group 1 (control; n=11): saline; group 2 (n=11): bevacizumab 5mg/ml; and group 3 (n=11): sunitinib 0.5mg/ml. A corneal NV model was used, based on sutures in the right eye of each rabbit. Each treatment was administered topically 3 times daily for 14 days. Corneas were then processed for the study of vascular microdensity (6 eyes) and vascular morphology analysis (5 eyes) using enzymatic staining histological techniques RESULTS: The vascular response in group 3 was limited to small-sized tree formations with various vascular axes compared with the extensive, lush and directional corneal NV of group 1 and 2. In the histological sections near the limb, there were no differences in vascular microdensity studies between the three groups. However, the mean sectional area of vessels (MSAV) in group 3 was 41.88% lower than in group 1 and 19.19% lower than in group 2. In distal sections, there were no differences between groups 1 and 2. However, group 3 was characterized by absence of vessels. CONCLUSIONS: Bevacizumab produced no changes in the morphology of the vessels or the vascular microdensity. Sunitinib reduced the size of the new vessels and induced changes in the vascular tree.

[Effects of Astragalus polysaccharides and Cordyceps sinensis mycelium mixture on the transforming growth factor-beta1 expression in chronic rejection of artery transplantation: experiment with rats].

OBJECTIVE: To explore the effect of Astragalus polysaccharides (APS) and Cordyceps sinensis (CP) mycelium mixture on the chronic rejection of artery transplantation. METHODS: The abdominal arteries of 180 Wistar rats were isolated and transplanted to 180 SD rats whose with their abdominal arteries resected. The 180 recipient SD rats were randomly divided into blank control group (n = 20), APS group (n = 40, receiving gastric perfusion of APS 1 mg/kg bid), APS + low-dose CP group (n = 40, receiving APS and CP mycelium powder 1.25 g/d), APS + medium-dose CP group (n = 40, receiving APS and CP mycelium powder 2.5 g/d), and APS + high-dose CP group (n = 40, receiving APS and CP mycelium powder 5 g/d). Thirty days later the SD rats were killed with the transplanted abdominal arteries taken out to undergo microscopy. The expression of transforming growth factor (TGF)-beta(1) in the transplanted artery was examined by immunohistochemistry. RESULTS: In the control group, overexpression of TGF-beta(1) was observed in the intimal smooth muscle cells, monocytes, arterial endothelial cells, and arteriole, venule, and blood capillary endothelial cells in extima. However, the expression levels of TGF-beta(1) in the APS group and the 3 mixture administration groups were all significantly lower, especially in the medium- and high-dose groups (all P < 0.01). Severe edema of arterial endothelial cells and proliferation of monocytes were observed microscopically in the control group. Under electron microscope, rough endoplasmic reticulum and Golgi body were abundant in the control group. While in the mixture administration groups these changes were either weakened or absent. CONCLUSION: Astragalus polysaccharides and Cordyceps sinensis mycelium polysaccharides mixture can decrease the expression of TGF-beta(1) and inhibit the synthesis of collagen in the transplanted arteries.

Effect of selenium compounds on the damage induced by oxysterol on rat arterial walls.

Wistar rats were fed Se-deficient (0.017 +/- 0.002 mg Se/kg) and Seadequate (0.32 +/- 0.045 Se mg/kg) diets for 12 mo and then were given 5 mg/kg of cholestane-3beta,5alpha,6beta-triol (3-triol), intravenously. Se compounds (Na(2)SeO(3) and ebselen) were supplemented in different doses and times to the Se-deficient rats. Twenty-four hours after 3-triol infusion, the changes in ultrastructures of rat aorta were examined by scanning electron micrography (SEM) and transmission electron micrography (TEM). SEM examinations showed that 3-triol induced diffused injuries on arterial endothelial urfaces of long-term Se-deficient rat, and a large number of holes or craterlike defects were observed. TEM examinations further showed that 3-triol induced swelling, necrosis, and shedding of endothelial cells, which resulted in the destruction of endothelial integrity. Meanwhile, smooth muscle cells proliferated and migrated toward intimae; the breakage of internal elastic lamina benefited the migration of smooth muscle cells. Supplemented with Na(2)SeO(3) (40 microg/kg, 10 d per continuum) and ebselen (20 mg/kg), respectively, exhibited significant protection from damages induced by 3-triol. It seems that protecting mechanisms were different between Na(2)SeO(3) and ebselen. The present investigation gave visual evidence that both injuries induced by cholesterol oxides and the Se nutritional status contributed to the development of atherosclerosis.

Comparison of angiotensin II-induced blood pressure and structural changes in Fischer 344 and Wistar Kyoto rats.

1. The purpose of the present study was to evaluate the blood pressure (BP) response, the BP and heart rate (HR) components of the startle reaction and the structure of the carotid artery and the aorta during chronic infusion of angiotensin (Ang) II in Fischer 344 (F344) compared with Wistar Kyoto (WKY) rats, two in-bred normotensive contrasted strains. 2. Osmotic mini-pumps filled with saline vehicle or AngII (120 ng/kg per min) were implanted subcutaneously in 8-week-old normotensive rats and infused for 4 weeks in F344 rats (saline, n = 10; AngII, n = 10) and WKY rats (saline, n = 10; AngII, n = 9). Basal BP, HR and the responses to an acoustic startle stimulus (duration 0.7 s, 115 dB) were recorded in conscious rats. The structure of the carotid artery and aorta was determined in 4% formaldehyde-fixed arteries. 3. Compared with WKY rats, vehicle-treated F344 rats had lower bodyweight (BW; 266 +/- 7 vs 299 +/- 9 g; P < 0.05) and heart weight (0.80 +/- 0.02 vs 0.98 +/- 0.04 g; P < 0.05) and higher aortic systolic BP (SBP; 131 +/- 1 vs 123 +/- 5 mmHg; P < 0.001) and diastolic BP (98 +/- 3 vs 89 +/- 2 mmHg; P < 0.001). In F344 rats, compared with the WKY rats, the wall thickness/BW ratio was increased in the carotid artery (156 +/- 9 vs 131 +/- 6 nm/g; P < 0.05) and abdominal aorta (264 +/- 13 vs 217 +/- 12 nm/g; P < 0.05) and decreased in the thoracic aorta (246 +/- 13 vs 275 +/- 8 nm/g; P < 0.05). There was no difference in elastin and collagen density. Angiotensin II differentially enhanced BP in both strains: (SBP: 163 +/- 5 and 132 +/- 4 mmHg in F344 and WKY rats, respectively; P(strain x treatment) < 0.05). Circumferential wall stress was increased in the aorta of F344 rats compared with WKY rats (1176 +/- 39 vs 956 +/- 12 kPa (P < 0.001) and 1107 +/- 42 vs 813 +/- 12 kPa (P < 0.001) in thoracic and abdominal aortas, respectively). The startle response was amplified in F344 rats, with enhanced increases in SBP and pulse pressure (PP) and bradycardia compared with responses of WKY rats (+44 +/- 9 mmHg, +10 +/- 2 mmHg and -40 +/- 17 b.p.m., respectively, in F344 rats vs+28 +/- 4 mmHg, + 4 +/- 2 mmHg and -19 +/- 10 b.p.m. in WKY rats, respectively; P(strain) < 0.05 for BP and PP). The startle response was not affected by AngII. 4. These results indicate a higher BP producing an increase in wall thickness in F344 rats compared with WKY rats. We propose that an increase in sympathetic nervous activity causes these haemodynamic differences, as suggested by the excessive increase in BP during an acoustic startle stimulus. Angiotensin II increased BP in F344 rats, but did not exaggerate the increase in BP during the startle reaction.

Effects of probucol on endothelial damage by 5-fluorouracil.

Cardiotoxicity is a serious side effect of cancer treatment with the commonly used drug 5-fluorouracil (5-FU). The pathophysiology of this is unclear. Experimental studies show a thrombogenic effect of 5-FU, secondary to a direct toxic effect on the endothelium, possibly mediated by radical generation. Probucol is a lipid-lowering drug with strong antioxidant properties. The aim of this study was to evaluate the possibility of using probucol treatment to protect against the toxicity of 5-FU on vascular endothelium of the central artery in the ears of rabbits. Five groups of rabbits were treated with 1) 5-FU, 2) saline, 3) probucol high-dose and saline, 4) probucol high-dose and 5-FU, 5) probucol low-dose and 5-FU. Damage to the arterial endothelium was evaluated by scanning electron microscopy. Damage to the endothelium in 5-FU + probucol-treated animals was minimal and comparable to that of the control group. Intima disruption or thrombus formation was seen with 5-FU only. The results of the study indicate that treatment with probucol prevents 5-FU-induced endothelial injury.

Beneficial effects of L-arginine supplementation in experimental hyperlipemia-hyperglycemia in the hamster.

The objective of this study was to evaluate whether administration of L-arginine, the substrate for nitric oxide synthesis, was able to ameliorate the endothelial dysfunction and the morphological changes induced by the combined insult of hyperlipemia and hyperglycemia. To this purpose, golden Syrian hamsters were rendered simultaneously hyperlipemic and diabetic (HD group) for 24 weeks, and then orally treated with 622.14 mg/kg per day L-arginine, for 12 weeks (HD + L-arg group). The following assays were carried out: (1) spectrophotometric: concentrations of circulating glucose, cholesterol, and creatinine, the activity of angiotensin-converting enzyme (ACE), and the osmotic fragility of erythrocyte plasmalemma; (2) myographic: the endothelium-dependent and -independent relaxation of the resistance arteries (i.d. 210-250 microm) to 10(-8) to 10(-4) M acetylcholine (ACh) or sodium nitroprusside (SNP); and (3) electron-microscopic: the ultrastructure of the resistance arteries, myocardium, and kidney glomeruli, which are main targets of hypertensive complications. The results showed that oral supplementation with L-arginine in simultaneous hyperlipemia-hyperglycemia induced in hamsters had favorable effects on: (1) homeostasis, i.e., diminished the concentration of circulating glucose (by ~63%) and cholesterol (by approximately 10%), reduced the ACE activity (by approximately 45%), and lowered the osmotic fragility of erythrocyte plasmalemma (as marker for the oxidative stress in plasma); (2) mesenteric resistance arteries, which showed (in 10(-4) M ACh) an improved endothelium-dependent relaxation (72.40+/-4.6% in the HD + L-arg group vs 61.90+/-1.45% in the HD group) and a reduced thickness (approximately 1.32-fold) of the smooth muscle cells' extracellular matrix; and (3) the heart, which displayed approximately 16% diminishing of the thickness of the left ventricular wall, and an apparently normal structure of the myocardium; the restoration of the thickness of the pericapillary extracellular matrix to almost normal dimensions was also observed. Administration of L-arginine did not modify the high level of plasma creatinine determined for the HD group (approximately 48% increased vs control group) and had no effect on the thickened, nodular basal lamina of the kidney capillaries. The results indicate that endothelial dysfunction established in combined hyperlipemia-diabetes is distinctive for each vascular bed (mesenteric arterioles, heart capillaries, kidney glomerular capillaries), and there is a reversible stage of the dysfunction in which L-arginine oral supplementation induced beneficial effects.

[Intervention treatment of hepatocellular carcinoma with 125I-lipiodol plus chemotherapeutic drugs and self body hairs: a report of 56 cases].

OBJECTIVE: To study the therapeutic effects on primary hepatic cancer of intervention treatment with a preparation consisting of 125I-iodinated lipiodol ultrafluid (LUF) plus self body hairs and cell-cycle nonspecific chemotherapeutic agents. METHODS: The treatment was given to 56 patients with primary hepatic cancer. CT, US, DSA, serum AFP determination, and urine radioactivity were carried out before and after treatment. RESULTS: The preparation was found to be held up in the end arteries supplying the tumor for a considerable length of time without passing through blood capillaries into the general circulation. It helped keep the chemotherapeutic drugs and internal radiation staying at the tumor site. The side effects of this treatment were tolerable. No rejection reaction was observed. In thirty six of the 56 patients (64.3%), the tumor reduced by 50%-70% in diameter, and in the remaining 20 patients(35.7%) the reduction in tumor diameter was less than 50% or not at all. The clinical manifestations, liver functions and serum AFP level improved in all cases. The survival rate in 6, 12, 24 and 36 months was 100%, 82.1%, 63.1% and 55.6%, respectively. CONCLUSION: The new intervention treatment for primary liver cancer herein described is easy to perform and can significantly improve survival and quality of life.

Dietary fish oil reduces microthrombi over atherosclerotic lesions in hyperlipidemic swine even in the absence of plasma cholesterol reduction.

We have investigated in swine the effect of fish oil additives to a butter-cholesterol hyperlipidemic diet (BT) on atherogenesis and thrombogenesis when average plasma cholesterol levels were kept similar in fish oil-treated and untreated BT groups. The studies included evaluation of lesion sizes and cell numbers, counts of adherent monocytes over lesions, and counts of platelet clumps (microthrombi) over lesions either attached directly to endothelium or to adherent monocytes. Anatomic sites studied for lesion development were the left anterior descending coronary artery (LAD), the distal 1/5 of the abdominal aorta, and a proximal portion of the thoracic aorta. Counts of attached monocytes and platelet clumps were made by scanning electron microscopy only for the LAD and expressed per mm2 of surface. The most striking new result was in regard to the platelet clumps. These were reduced by the fish oil from 996 +/- 295/mm2 in the untreated BT group to 313 +/- 59 and 364 +/- 105 in BT+cod liver oil and BT+menhaden oil groups, respectively. Most of the platelet clumps were adherent to attached monocytes in all groups and the number of attached monocytes were greatly reduced by the fish oil additive. Thus there were close relationships among platelet clumps, monocytes, and lesion endothelium. Numbers of attachments over nonlesion endothelium were much less than those over lesions in all dietary groups. The most surprising result was the lack of retardation of lesion growth by the fish oil additives in spite of the reduction in attached monocytes and platelet clumps. In previous studies where the high plasma cholesterol levels in the BT swine had been modestly reduced (about 25%) there had been a marked retardation of lesion growth. The current result suggests that plasma cholesterol is the major factor controlling lesion growth in this model through under milder conditions and longer observation periods other factors might become apparent.

Effects of chronic absorption of dietary supplements of methionine and cystine on arterial morphology in the rat.

Male Wistar rats were fed diets containing supplements of either methionine or cystine from 10 weeks of age and compared to rats fed a control diet or a high protein diet kept under identical conditions. At 11-16 months of age, the aorta and the renal, iliac and caudal arteries of all rats were fixed and examined by light and electron microscopy. Cystine-fed rats showed arterial morphology similar to that of control rats and of those having received a high protein diet. Methionine-fed rats showed marked thickening of the arterial wall which was due, on the one hand, to massive intimal thickening, as a result of accumulation of granular material in the subendothelial region and, on the other hand, to marked thickening of the media as a result of increased extracellular material around smooth muscle cells. Zones of early phases of chondroid metaplasia were also observed in the media. Thus cystine and methionine, despite their interrelated metabolism, have very different effects on the morphology of the arterial wall. However, cystine and methionine both inhibited the spontaneous rupture of the internal elastic lamina in the renal artery. This latter result is discussed in the light of the similarities between spontaneous rupture of the internal elastic lamina and beta-aminopropionitrile-induced aortic aneurysm and rupture.

Effects of long term consumption of fish oil (Maxepa) on serum lipids and arterial ultrastructure in Japanese quail (Coturnix coturnix japonica).

Both random (U.C. Davis) and inbred ("Sea") Japanese quail were fed 8.6% dietary supplements of lard (SF) or fish oil (FO) Maxepa (38% of calories from fat) and 9 months later selected blood vessels were subjected to light and electron microscopy. Serum lipids were measured by means of automatic enzymatic analyses (Beckman Astra and Dupont ACA) following fasting (12-14 h) bleeding times taken at autopsy. VLDL and LDL were determined indirectly. Fatty acid profiles were done on pericardial fat from selected animals. All FO-fed quail averaged 22-48% increase in bleeding time when compared to diet controls or animals fed saturated fat (P less than 0.005). There was a 20% decrease in triacyglycerol (TG) and very low density lipoprotein (VLDL) in the random bred group (P less than 0.01). TG rose in the Sea Quail (NS). Low density lipoprotein (LDL) increased in both random (P less than 0.05) and inbred quail (P less than 0.05), but total cholesterol (TC) significantly increased only in the inbred birds (P less than 0.01). The HDL/LDL ratios in the FO groups were lower than in the controls. SF-fed animals had some fatty streak and/or fatty point formation in their coronary arteries and great vessels. FO-fed birds showed some fat deposits in their coronary arteries and greater accumulation (foam cells) within their great vessels with subendothelial protrusions into the lumen. It is suggested that these latter results may be a response to the relatively higher levels of cholesterol in FO (600 mg/100 g oil) versus SF (95 mg/100 g fat).(ABSTRACT TRUNCATED AT 250 WORDS)

Thalamic arterial pattern: an endocast and scanning electron microscopic study in normotensive male rats.

Rat cerebral vasculature serves as a model for study of the pathophysiology of stroke in humans. Human thalamic arteries show a high incidence of stroke. The objective is to describe the thalamic arterial vascular pattern in normotensive male rats as the initial step for quantitative histochemical studies of enzyme activities in the walls of these vessels. Intracardiac injections of methyl methacrylate monomer provide detailed vascular endocasts. The thalamic vascular bed defined by in situ dissection, serial reconstruction, and light and scanning electron microscopy of endocasts contained four groups of vessel: ventral medial thalamic arteries, thalamic branches from the posterior cerebral artery, and ventral lateral and ventral anterior thalamic arteries. Thalamic vessels are muscular arterioles that, after three to four bipinnate branches, feed into a continuous capillary bed (no loops). The parent vessels and their subsequent branches have been evaluated in terms of their mean internal diameters, mean interbranch intervals, and branch angles. The arterial patterns to rat and human thalami are very similar, with the exception of the anterior choroidal artery which is missing in the rat. The branches supplying the thalamus in both the rat and human are closely associated with the circle of Willis; however, the constituent parts of the circle in rat vary from the pattern in human brain. The rat thalamic arteries show morphological features similar to those seen in the stroke-prone ganglionic arteries in the human basal ganglia.

The rat-tail artery maintained in culture: an experimental model.

The rat-tail artery was maintained in vitro for 2 weeks to investigate its suitability as an experimental model. The criteria were that (a) it should retain the overall histological organization with normal ultrastructural appearance of the smooth-muscle cells; (b) stored neurotransmitter which could be activated by experimental treatment should be absent; and (c) smooth-muscle ion transport mechanisms should fall within normal range. Vessels were maintained in Falcon tissue-culture dishes in Dulbecco's modified Eagle's medium. Either 2% or no serum supplement was found to be more suitable than 10% serum due to the high rate of cell proliferation induced by the latter. Light and electron microscopy of cross sections of the vessels indicated that the overall normal vessel architecture was retained, and the ultrastructural features predicted normal function. There were no discernible differences dependent on the length (up to 8- to 10-cm lengths) of the cultured vessel. Preliminary experiments with fluorescent microscopy showed that stored neurotransmitter in the nerves of the vessel wall was no longer present after 48 hr. Ultrastructural examination revealed that storage vesicles in vitro lost their dense cores, representing noradrenalin, between 41 and 48 hr in culture. Normal ion transport mechanisms were retained in the smooth-muscle cells of the arteries in vitro for up to 2 weeks when tested with ion-specific electrodes. Morphological and physiological evidence support the suitability of the rat-tail artery as a model for experimental testing of vascular tissues.

Can the pituitary secrete directly to the brain? (Affirmative anatomical evidence).

Vascular casts of 10 rhesus monkey pituitary glands and three vascular casts of the rhesus monkey cavernous sinus were examined by scanning electron microscopy. A continuous neurohypophyseal capillary bed was found uniting the infundibulum, infundibular stem, and infundibular process. The neurophypophysis was supplied by three groups of arteries: superior hypophyseal, middle hypophyseal, and inferior hypophyseal. Numerous anastomoses were found between individual arteries, and some hypophyseal arteries formed anastomotic links between different portions of the circle of Willis. Veins located at the caudal pole of the infundibular process, capillaries linking the infundibulum to the hypothalamus, and portal vessels extending from the infundibulum to the adenohypophysis provided efferent vascular pathways from the neurohypophysis. The adenohypophysis received no direct arterial supply; its entire afferent vascular supply was provided by portal vessels. Lateral hypophyseal veins were not found; small adenohypophyseal veins joined larger neurohypophyseal veins to form confluent pituitary veins which extended to the cavernous sinus. The capacity of the venous connections draining the adenohypophysis directly to the cavernous sinus appeared small when compared to that of of the long portal vessels supplying the adenohypophysis. However, many of the short portal vessels interposed between the adenohypophysis and the infundibular stem and process were well arranged to function as alternative efferent routes from the adenohypophysis. The limited potential for venous drainage directly to the cavernous sinus suggests that blood leaves the adenohypophysis by other routes; blood carried via long portal vessels from the infundibulum to the adenohypophysis may return to the neurohypophyseal capillary bed via short portal vessels. This anatomical study suggests that hypothalamic and adenohypophyseal secretions are conveyed to the capillary bed of the neurohypohysis. These secretions may leave the neurohypophysis via any of seven potential routes: one efferent route is directed to the adenohypophysis, another route is directed to the systemic circulation, but five of the potential efferent routes are directed toward the brain.