Hypertensive stroke-prone rat

Hernandez N. E., MacDonald J. S., Stier C. T., Belmonte A., Fernandez R., and Karpiak S. E. (1994). GM ganglioside treatment of spontaneously hypertensive stroke prone rats. Exp. Neurol. 126 95-100. 

The first indication that butylphthalide (30) and its two enantiomers 31 (3R-) and 32 (35-) have anti-stroke properties was based on their abilities to delay stroke occurrence and to prolong post-stroke life span in spontaneous hypertensive stroke-prone rats [310], Adopting the middle cerebral artery occlusion (MCAO)-induced focal ischemia rat model, Feng et al. demonstrated that 30, 31 and 32 decreased infarct size [311, 312], This finding may be related to their abilities to increase regional cerebral blood flow [313-315] and arteriole diameter [315]. Phthalides 30, 31 and 32 lessened MCAO-induced inflammation [316], and reduced cerebral edema [317, 318] and blood-brain barrier permeability [318]. In addition, these three phthalides caused a beneficial post-MCAO learning improvement in an active avoidance test [319], The protective activities of 30, 31 and 32 on cerebral injuries are summarized in Table 4. 

Male Sprague Dawley or spontaneously hypertensive stroke prone Wistar or Lewis rats with adjuvant induced arthritis weighing 150-300 g or New Zealand rabbits with arteriosclerosis induced by cholesterol feeding for 3 months are used. The animals receive the test compound by oral, intravenous, intraperitoneal, or subcutaneous administration. Control animals are treated with vehicle alone. Prior to thrombus induction, the animals are pretreated by s.c. injection of... 

UCHIDA S, OZAKI M, KASHI T, YAMASHITA K, NIWA M and TANIYAMA K (1995) Effects of (-)-epigallocatechin-3-O-gallate (green tea tannin) on the life span of stroke-prone spontaneously hypertensive rats , Clin Exp Pharmacol, 11 (Suppl 1), S302-303. 

Kirsch T, Wellner M, Luft FC, Haller H, Li ppoldt A. Altered gene expression in cerebral capillaries of stroke-prone spontaneously hypertensive rats. Brain Res 2001 910 106-115. 

Napoli et al. [286] found that the nifedipine treatment of stroke-prone spontaneously hypertensive rats (SPSHR) suppressed the plasma and LDL oxidation and the formation of oxidation-specific epitopes and increased the survival of rats independently of blood pressure modification. Their results suggest that the protective effects of calcium blockers of dihydro-pyridine-type on cerebral ischemia and stroke may, at least in part, depend on their antioxidant activity. In vivo antioxidant effect of nilvadipine on LDL oxidation has been studied in hypertensive patients with high risk of atherosclerosis [287], It was found that there was a significant decrease in the level of LDL cholesterol oxidation in patients after nilvadipine treatment. 

Sunderland T, Tariot PN, Newhouse PA. (1988). Differential responsivity of mood, behavior, and cognition to cholinergic agents in elderly neuropsychiatric populations. Brain Res. 472 4y. 371-89. Tachikawa E, Kudo K, Flarada K, Kashimoto T, Miyate Y, Kakizaki A, Takahashi E. (1999). Effects of ginseng saponins on responses induced by various receptor stimuli. EurJ Pharmacol 369(1) 23-32. Tagami M, Ikeda K, Yamagata K, Nara Y, Fujino FI, Kubota A, Numano F, Yamori Y. (1999). Vitamin E prevents apoptosis in hippocampal neurons caused by cerebral ischemia and reperfusion in stroke-prone spontaneously hypertensive rats. Lab Invest. 79(5) 609-15. 

Otani, L., Ninomiya, T., Murakami, M., Osajima, K., Kato, H., and Murakami, T. (2009). Sardine peptide with angiotensin I-converting enzyme inhibitory activity improves glucose tolerance in stroke-prone spontaneously hypertensive rats. Biosci. Biotechnol. Biochem. 73, 2203-2209. 

Xu JW, Ikeda K, Yamori Y. 2004. Genistein inhibits expressions of NADPH oxidase p22phox and angiotensin II type 1 receptor in aortic endothelial cells from stroke-prone spontaneously hypertensive rats. Hypertens Res 27 675-83. 

Impaired expression of Trx-1 in spontaneously hypertensive (SHR) and stroke-prone SHR (SHRSP) rat hearts have been documented (Tanito et al. 2004). Induction of thioredoxin was further reduced upon angiotensin II treatment of peripheral blood mononuclear cells isolated from those animals as compared to control Wistar Kyoto rats. Reduced expression of thioredoxin during hypoxia and reoxygenation of cortical neurons isolated from stroke-prone spontaneously hypertensive rats has also been reported (Yamagata et al. 2000). In another related study, serum Trx concentration in the hypertensive patients were found to be significantly higher than that of normal patients (Miwa et al. 2005). 

Yamagata, K., Tagami, M., Ikeda, K., Yamori, Y., and Nara, Y. 2000. Altered gene expressions during hypoxia and reoxygenation in cortical neurons isolated from stroke-prone spontaneously hypertensive rats. Neurosci. Lett. 284 131-134. 

Mizutani, K., Ikeda, K., Kawai, Y., and Yamoii, Y. 1999b. Extract of wine phenolics improves aortic biomechanical properties in stroke-prone spontaneously hypertensive rats (SHRSP). J Nutr Sci Vitaminol (Tokyo) 45 95-106. 

Sato, A., Huang, M. Z., Watanabe, S., Okuyama, H., Nakamoto, H., et al., Protein carbonyl content roughly reflects the unsaturation of lipids in muscle but not in other tissues of stroke-prone spontaneously hypertensive strain (SHRSP) rats fed different fats and oils. Biol. Pharm. Bull. 21, 1271-1276 (1998). 

Minami M, Kimura S, Endo T, Hamaue N, Hirafuji M, To-gashi H, Yoshioka M, Saito H, Watanabe S, Kobayashi T, Okuyama H. Dietary docosahexaenoic acid increases cerebral acetylcholine levels and improves passive avoidance performance in stroke-prone spontaneously hypertensive rats. Pharmacol. Biochem. Behav. 1997 58 1123-1129. 

Sesamin, the most abundant lignan present in sesame seed and sesame oil, was demonstrated to suppress the development of hypertension in rats induced by deoxycorticosterone acetate (DOCA) and salt (127). Dietary sesamin was also reported to effectively prevent the elevation of blood pressure and cardiac hypertrophy in two-kidney, one-clip (2k, Ic) renal hypertensive rats (128). In the stroke-prone spontaneously hypertensive rats (SHRSP), sesamin feeding was much more effective as an anti-hypertensive regimen in salt-loaded SHRSP (with 1% salt in drinking water) than in unloaded SHRSP (129). 

Kawasliima S, Yamasliita T, Miwa Y, OzaM M, Nanriki M, Hirase T, Inoue N, Hirata K, Yokoyama M (2003) HMG-CoA reductase inliibitor has protecdve effects against stroke events in stroke-prone spontaneously hypertensive rats. Stroke 34 157—163. 

C in platelets from Wistar Kyoto rat and stroke-prone spontaneously hypertensive rat Thromb. Res. 82,417-427,1996. 

Spontaneously hypertensive rats can be used to screen compounds for antihypertensive effects and for effects on heart rate. The animals are dosed for one or a few days. Blood pressure and heart rate are measured by means of an inflatable cuff around the tail. Most classes of antihypertensives will be detected. Agents such as beta-adrenergic antagonists will be detected by decreased heart rate. Other rat models include deoxycorticosterone acetate (DOCA)-induced hypertensive, renal hypertensive (one or both renal arteries clamped), and stroke-prone spontaneously hypertensive rats. Hypertensive dogs produced by clamping one or both renal arteries may also be used to test or verify antihypertensive activity in a second species. 

Napoli C, Salomone S, Godfraind T, Palinski W, Capuzzi DM, et al. 1999. 1,4-Dihydropyridine calci um-channel blockers inhibit plasma and LDL oxidation, formation of oxidation-specific epitopes in the arterial wall and prolong survival in stroke-prone spontaneously hypertensive rats. Stroke 30 1907-15... 

With regard to neurotransmitters, we found no significant difference in the levels of norepinephrine, 3,4-dihydrophenylacetic acid, dopamine, 5-hydroxyindoleacetic acid, homovanilinic acid, and serotonin in the frontal cortex, the hippocampus, and the striatum between conventional rats fed the safflower-oil diet and those fed the perilla-oil diet. The acetylcholine (Ach) level was very high in the striatum, but these diets had no effect on the Ach levels in brain regions (Fig. 6). In stroke-prone spontaneously hypertensive rats, DHA supplementation increased Ach levels in the frontal cortex and the hippocampus compared with those fed the safflower-oil diet (Minami, 1997a,b). 

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