Kidney hydronephrotic 49

The antioxidant ethoxyquin (94) is conceptually similar to (88) in that it contains a benzene ring with two heteroatoms in a 1,4-relationship, one of which lies in a dihydroaromatic ring. This compound was reported to inhibit the release of LO products from rat ISN, although it was more potent against CO [244]. Orally-dosed ethoxyquin inhibited cell influx in a rabbit hydronephrotic kidney model [245], and was anti-inflammatory in guinea-pig UV erythema [246]. No relationship was drawn between these activities and 5-LO inhibition. 

The hydronephrotic kidney was developed for in vivo visuahzation of the glomerular microcirculation, the vas afferens and the vas efferens [138]. This preparation utihzes postischemic hydronephrosis (PIH) to destroy the renal tubular system while preserving a portion of the cortex. In this preparation, glomeruli and... 

The advantages of the hydronephrotic kidney preparation in examining the renal micro-vasculature are as follows 1) It is possible to determine the real flow direction in both pre- as well as post-glomerular elements of the microvasculature a three-dimensional way 2) the circulatory network is preserved such that the pressure and flow effects of changes in resistances in one vascular segment can be determined in the adjacent upstream and downstream vessels 3) the circulation can be examined without the trauma related to microdissection 4) both outer and inner cortical microvessels can be studied. 

Limitations of the technique include 1) The induction of hydronephrosis may alter vasoreactivity 2) tubular atrophy eliminates tubular influences on the microcirculation such as those observed in the tubu-loglomerular feedback phenomenon and 3) intrinsic vascular resistances are higher and blood flows lower in hydronephrotic compared to normal kidneys. 

Many important observations regarding segmental changes in the renal microcirculation to physiologic, pharmacologic and toxic stimuli have been made with hydronephrotic kidney preparation. 

Table 10. Hydronephrotic kidney Effects of endogenous effectors.

Both the hydronephrotic kidney and the juxtamedullary model have been used primarily for physiological studies, including studies of drug action, whereas the IPRK has been used extensively for the studies of pathophysiology as well. Consequently the main focus of this section will be the intact IPRK, which is both the simplest and the most widely used model. The other two models will be discussed in greater detail in section 4 of this chapter. 

Flayashi K, Epstein M, Eoutzenhiser R Pressure-induced vasoconstriction of renal microvessels in normotensive and hypertensive rats. Studies in the isolated perfused hydronephrotic kidney. Circ.Res. 65 1475-1484,1989... 

Fretschner M, Endlich K, Gulbins E, Eang RE, Schlottmann K, Steinhausen M Effects of endothelin on the renal microcirculation ofthe split hydronephrotic rat kidney. Ren Physiol Biochem. 14 112-127,1991... 

Flayashi K, Fujiwara K,Oka K, NagahamaT, Matsuda FI, SarutaT Effects of insulin on rat renal microvessels studies in the isolated perfused hydronephrotic kidney. Kidney Int 51 1507-1513,1997... 

Flayashi K,WakinoS, Ozawa Y, Flomma K, KandaT,Okubo K, Takamatsu l,TatematsuS, Kumagai El, SarutaT Role of protein kinase C in Ca channel blocker-induced renal arteriolar dilation in spontaneously hypertensive rats-studies in the isolated perfused hydronephrotic kidney. Keio Journal of Medicine 54 102-108,2005... 

Flayashi K, Ozawa Y,Wakino S, KandaT, Flomma K,Takamatsu l,Tatematsu S, SarutaT Cellular mechanism for mibefradil-induced vasodilation of renal microcirculation studies in the isolated perfused hydronephrotic kidney. Journal of Cardiovascular Pharmacology 42 697-702, 2003... 

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