No abstract available.
Rabbits*

No abstract available.
Rabbits*

No abstract available.
Rabbits*

No abstract available.
Rabbits*

No abstract available.
Rabbits*

Roles of the nonclipped kidney in the development and maintenance of the high blood pressure in two- kidney, one clip hypertension remain to be defined. It has been known that the pathophysiology of hypertension is different by the presence or absence of the contralateral kidney in renal hypertension. The present study was undertaken to evaluate the effects of intrarenal norepinephrine in the nonclipped kidney exposed to the high blood pressure. Experiments were performed in 7-day two-kidney, one clip Goldblatt hypertensive and sham-operated normotensive rabbits. The basal levels of renal plasma flow and urine flow, and urinary excretion of electrolytes were higher in the nonclipped kidney of two-kidney, one clip Goldblatt hypertensive than in the corresponding kidney of sham-operated normotensive rabbits. Intrarenal infusion of norepinephrine increased renal perfusion resistance, and decreased renal hemodynamics and renal excretory function in a dose-dependent manner in both hypertensive and normotensive rabbits. The renal hemodynamics and excretory responses to intrarenal norepinephrine infusion were attenuated in two-kidney, one clip Goldblatt hypertensive rabbits. The changes by norepinephrine infusion of the renal excretory function were closely correlated with those in glomerular filtration rate or renal plasma flow. These results suggest that the impaired vascular reactivity in the nonclipped kidney is one of the early changes appeared in the course of multifactorial derangements in renal hypertension and that the impairment may be an adaptive response of the kidney to high blood pressure.
Rabbits ; Animals

Renin-angiotensin system is associated with development of diabetic nephropathy. Hyperglycemia is known as a primary etiologic factor about it. Thus, we investigated the effect of high glucose on angiotensin II(ANG II) binding in the primary cultured rabbit renal proximal tubule cells(PTCs). 25 mM glucose(48 hr incubation) induces inhibition of ANG II binding. The high glucose-induced inhibition of ANG II binding was recovered by the removal of glucose, suggesting the role of glucose specificity. High glucose-induced inhibition of ANG II binding was blocked by mepacrine and AACOCF3, phospholipase A2(PLA2) inhibitors. Indomethacin, a cyclooxygenase inhibitor, significantly prevented high glucose-induced inhibition of ANG II binding. However, nordihydroguaiareic acid(NDGA), a lipoxygenase inhibitor, and econazole, a cytochrome P450 epoxygenase inhibitor, did not block the effect of high glucose. This result suggest that cyclooxygenase metabolites of arachidonic acid(AA) released by high glucose are involved in the high glucose-induced inhibition of ANG II binding. Next, we examined the involvement of PKC in the effect of high glucose. Staurosporine, bisindolylmaleimide I, protein kinase C(PKC) inhibitors, and PD 98059, a p44/42 mitogen activated protein kinase(MAPK) inhibitor, significantly blocked high glucose- induced increase of [3H]-AA release and inhibition of ANG II binding. Indeed, 25 mM glucose increased PKC activity from cytosolic to particulate fraction and phosphorylation of p44/42 MAPK. In addition, high glucose increased phosphorylation of p44/42 MAPK and its activation was significantly blocked by PKC inhibitor. In conclusion, high glucose partially inhibits ANG II binding via PKC-MAPK-PLA2 signal pathway in the PTCs.
Rabbits ; Animals

Apraclonidine is a potent alpha-adrenergic agonist that, like clonidine, is relatively selective for alpha-2 receptors. Apraclonidine has been shown to lower intraocular pressure by diminishing aqueous humor formation. The purpose of this study is to know the morphological changes in the ciliary epithelium by apraclonidine against aqueous formation. In group I, two drops of 1% apraclonidine hydrochloride were instilled on the right eye of the pigmented rabbits and the eyes were enucleated on 1,2.6 and 24 hours after instillation to find out the duration of action of the drug and the tissue response. In group II, one drop was instilled twice daily for seven days on the right eye and the eyes were enucleated on 1, 2 and 5 days after cessation of the instillation observing the cumulative effect of the drug and the tissue response. These eyes were studied with electron mIcroscopIc examiation. As a result, widening of cell membranes(basal infoldings) of the non-pigmented epithelium(NPE) were observed. This change was recovered with time, and seems to be the principal morphological changes of apraclonidine against aqueous formation in the ciliary body. In group II, the cellular changes were minimal except for well developed rough endoplasmic reticulum representing resumed secretary function of the cell.
Rabbits ; Animals

Under the postulation that double Ruiz procedure could increase the effect of radial keratotomy(RK), RK combined with horizontal and vertical Ruiz procedure was performed in three groups of 22 rabbit eyes. In the group A of six eyes, RK with vertical Ruiz procedure was performed, and eight weeks later the horizontal Ruiz procedure was added. In the group B of eight eyes, RK with horizontal Ruiz procedure was performed, and four weeks later the vertical Ruiz procedure was added. In the group C of eight eyes, RK with horizontal and vertical Ruiz procedure were performed simultaneously. As a control, in the group D of eight eyes, RK without Ruiz procedure was performed. Changes in keratometry for four weeks and eight weeks postoperatively were analyzed. The results were as follows: 1. At eight weeks postoperatively, mean changes in keratometry were 6.434D, 3.663D, 4.030D and 1.585D in groups A,B,C and D, respectively. 2. Mean changes in keratometry of groups A,B and C were significantly higher than that of group D. 3. Mean change in keratometry of 6.434D in group A was significantly the highest of the three groups in which the double Ruiz procedure was performed. From the above results, it was concluded that the double Ruiz procedure increased the effect of RK and that the procedure was more effective when secondary Ruiz procedure was added eight weeks later.
Rabbits ; Animals

No abstract available.
Ephedrine* ; Rabbits*