Features of intracellular calcium distribution in the adipose tissue of spontaneously hypertensive rats (SHR)

The in vitro study of the kinetics of 45Ca efflux from adipose tissue of rats reveals 3 pools of exchangeable calcium. Calcium content in the intracellular pools of adipose tissue of spontaneously hypertensive rats is increased as compared to that in normotensive controls.     

Hypothalamus-adenohypophysis-thyroid axis in spontaneously hypertensive rats (SHR)

Summary Increased basal TSH levels and an enhanced response to cold-exposure were apparent in the SHR accustomed to +30°C, whereas goitres and an increased amount of the anterior pituitary TSH were measured in SHR kept at +20°C.These studies were supported by grants from the Academy of Finland and Orion Pharmaceuticals Company, Helsinki. The technical help of Mrs Anneli v. Behr is greatly acknowleged.     

Structural basis for resetting of baroreceptor regulation in spontaneously hypertensive rats (SHR)

Zusammenfassung Nachweis, dass in Ratten mit genetischem Hochdruck und normalem Herzrhythmus Verdickungen des Endotheliums im Karotissinus und im Aortabogen beobachtet werden. Eine Hypertrophie der Gefässmuskulatur war nachweisbar, was zu einer Abschwächung des Drucksignals zur Stelle der Pressorezeptoren führte. Diese dürften teilweise verantwortlich sein für die Verschiebung der Pressorezeptor-Steuerung bei genetisch hypertensiven Ratten.

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This study is partly supported by I.W.O.N.L.     

Central influence of vasopressin on baroreceptor reflex in normotensive rats and its lack in spontaneously hypertensive rats (SHR)

Summary In normotensive Wistar rats intracerebroventricular (i.c.v.) injection of 30 mU of lysine⁸-vasopressin enhances significantly the cardiovagal reflex bradycardia induced by a blood pressure rise. This effect is absent in spontaneously hypertensive rats (SHR) of the Okamoto strain.     

Dopamine-beta-hydroxylase activity in stroke-prone spontaneously hypertensive rats

Dopamine-beta-hydroxylase (DBH) activity was higher in the serum, the mesenteric artery and the cerebral cortex of 4-week-old stroke-prone spontaneously hypertensive rats (SHRSP), and lower in the nucleus tractus solitarii than it was in spontaneously hypertensive rats (SHR).     

Polyphosphoinositide metabolism in erythrocytes from spontaneously hypertensive rats

Summary Incorporation of³²P into di- and triphosphoinositides of erythrocytes from 1-month-old spontaneously hypertensive rats was lower, and diphosphoinositide content higher, than in controls. During development of hypertension these initial differences decreased and were even reversed.     

Polyphosphoinositide metabolism in erythrocytes from spontaneously hypertensive rats

Incorporation of 32P into di- and triphosphoinositides of erythrocytes from 1-month-old spontaneously hypertensive rats was lower, and diphosphoinositide content higher, than in controls. During development of hypertension these initial differences decreased and were even reversed.     

Serum dopamine-β-hydroxylase in spontaneously hypertensive rats

Zusammenfassung Es wird gezeigt, dass die Dopamin--Hydroxylase-Aktivität im Serum bei spontan hypertonischen Ratten im Vergleich zu normotonen Kontrollen nicht verändert ist.     

Monoamine oxidase activity in tissues of spontaneously hypertensive rats

Summary Monoamine oxidase (MAO) activity was assayed both in central and peripheral blood vessels of spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar Kyoto rats (WKR). The activity of MAO in the brain and peripheral vasculature was essentially the same in both SHR and WKR. It can therefore be concluded that central and peripheral vascular MAO activity is not altered in the genetically hypertensive animals.     

Tissue catecholamines following renal denervation in spontaneously hypertensive rats

Summary The delay in blood pressure increase observed in spontaneously hypertensive rats following bilateral renal denervation appeared to be due to a temporary reduction of the renal catecholamines content.This work was supported by grants from the Institut National de la Santé et de la Recherche Médicale (ATP 32-76-64, and AU 79-35) and from the Fonds National Suisse de la Recherche Scientifique (3.033.76)     

Blood pressure and impairment of endothelium-dependent relaxation in spontaneously hypertensive rats

Summary Correlation between hypertension and impairment of endothelium-dependent relaxation was demonstrated using aortae from certain strains of rats with various levels of spontaneous hypertension. It was also observed that the impairment of endothelium-dependent relaxation is the secondary change due to hypertension, and the level and duration of hypertension is the determinant factor of the impairment.     

Lower limit of cerebral autoregulation in normotensive and spontaneously hypertensive rats

Summary Cerebral autoregulation was examined in NTR and SHR. The lower blood pressure limit of autoregulation being 95 mm Hg in SHR was shifted upwards from 62 mm Hg in NTR.     

Enhanced reactivity towards flunarizine in cerebrovascular bed of spontaneously hypertensive rats

Cerebral blood flow (CBF) was measured and cerebrovascular resistance (CVR) was calculated in anesthetized spontaneously hypertensive rats (SHR) and normotensive rats (NR) following the administration of incremental dosages of i.v. flunarizine or papaverine. CBF and CVR changes following papaverine were the same in both groups of rats irrespective of the dose of the drug. The effect of flunarizine was much more pronounced in SHR than in NR. The results point out the greater dependency of basal cerebrovascular tone in SHR upon Ca2+ influx into vascular smooth muscle cells.     

Quantitative immunofluorescence of tyrosine hydroxylase in the adrenal medulla of spontaneously hypertensive rats

The amount of tyrosine hydroxylase protein in the adrenal medulla, which was estimated by a quantitative immunofluorescence method, was higher in spontaneously hypertensive rats than in normotensive control Wistar-Kyoto rats at 4 and 16 weeks of age before and after the development of hypertension.     

Quantitative immunofluorescence of tyrosine hydroxylase in the adrenal medulla of spontaneously hypertensive rats

Summary The amount of tyrosine hydroxylase protein in the adrenal medulla, which was estimated by a quantitative immunofluorescence method, was higher in spontaneously hypertensive rats than in normotensive control Wistar-Kyoto rats at 4 and 16 weeks of age before and after the development of hypertension.This study was supported by grants from the Ministry of Education, Science and Culture, Japan (No. 59570018). Reprint requests to I.N., Department of Anatomy, School of Medicine, Fujita-Gakuen Health University, Toyoake, Aichi 470-11 (Japan).