Experimental chronic hypertension in the rabbit

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AMER](]AN }~E:IRT JOURNAL

Mood pressure was essentially the same (29=2 per ee'nt) as ~ Ihe 1 year oid greup, The systoUc ble(~d p r e s s u r e for 2 year Md vitami~ E deflcie;~t ~ats and m ~ m M c~m 1:7ol fats was 6].7 ram. a n d 87.'; ram., respe..:iively. A loweri~/g of the bh/ed pressure i.u the second .year of l i f e is reflected 4~qtm,lly in both experime~ltai and eoni;ro~ groups. This r e d u c t i o n is t h e r e f o r ( d~a i;) ~iu a g i n g effect ai~d i fret a m ~ n i f e s t a t i m l <)f a d i e t a r y deficiency. An ]dstologi<: exa ~dn:~tkm of ihe !+arts a n d iarg.q vessels of v i t a m i n E deficient rats failed to d~!mns~raW~ a n y co~:asient w~s~m[a~ [esio'ns ~hat m i g h t c o n t r i b u t e to a redaed{m (if iJood pressure. ~,.a~iations JR the o o ~ temperal.ure, age a n d sex oJ" the anim~l, ~md m e t h o d s use< n determinir~g blood p r e s s u r e are variables l h a t influence the hi(rod pressm'e ?end:rags in nornml ~nd e x p e r i m e n t a l rats. Ai 'I'HORS

Quinby, W. C., Dexter, L , Sandmeyer, jo A., and Hayne% F . W . : The Renal Humoral Pressor Mechanism in Man. II+ The Effect of Transitory Complet~ Constriction of the Human Renal A r t e r y on Blood Pressure and on the Concentration of Renin, Hypertensinogen, and Hypertensinase of Renal ArteriaI and Venous Blood, With Animal Observations. J. C]in. I ~ v e s t i g a t i o n 24: 69, 1945. Complete constriction of the, renal artery b. :five p a t i e n t s ~i,~ h~ s~x dogs, f o r a period of twelve minutes, produced no r~se in blood pressure a f t e r release of fl~e c l a m p b u t did liberate small a m o u n t s of renin into the renM venous blood of the two p a t i e n t s in w h o m it was e s t i m a t e d and i~ ~wo of six dogs° I n p a t i e n t s , t h e c o n c e n t r a t i o n of h y p e r t e n s i n o g e n w a s ~he same in the renal a r t e r i a l a n d venous blood, before and a f i e r coustrietion of the renal artery, with one exception; h y p e r t e n s i n a s G determined at ~ p H of 7.3 an:{ i=5j was ]ikewise ihe sa llle,

These observations d e l n o n s t r a t e tha.t b 3 (.,onstrietion of t h e +'enal a r t e r y m man, the renal h u m o r a l pressor m e c h a n i s m is s t i m u l a t e d to activity as in animals~ AUTHORS=

Haynes, 1~. W., and Dexter, :15.: The Renal Humoral Pressor Mechanism in Man. III. The Hypertensinase Content of Plasma, of Control Subjects and of Patients With Hypertension and Other Diseases. J. Clim ]~vestigation 24: 75~ 1!)45~ The h y p e r t e n s i u a s e c o n t e n t of n j u s t i f i c a t i o n ~or c o n s i d e r i n g t h a t the blood p r e s s u r e is high in h u m a n hyper~enston because of a deficiency of h y p e r t e n s i n a s e in plasma. A UTH{mS. Grollman, A.: Experimental Chronic Hypertension in the t~abbit. 142: 666, ]944.

Am. J. PhysioL

T h e blood i)ressure o1' a d u l t r a b b i t s was followed for three m o n t h s or more f o b lowing various operative procedures on the kidneys. The averaKe rise in blood pressure following u n i l a t e r a l conlpression of lhe kidney did not oxt:eed tlH~t whi(~b fo~ h>wed u n i l a t e r a l nephrectomy= Removal of lhe compressed kidney iu a hvpertensiv,, a n i n m l did not result in lowering of the blood pressure. Ral->bi~s m a y exhibit hypeitension even in the absence of all renal t i s s u e The implications of t h e observed results on ti~e a u t h o r ' s ~