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The APS Journal Legacy Content is the corpus of 100 years of historical scientific research from the American Physiological Society research journals. This package goes back to the first issue of each of the APS journals including the American Journal of Physiology, first published in 1898. The full text scanned images of the printed pages are easily searchable. Downloads quickly in PDF format.

1. The effect of sodium pentobarbital and Inactin anaesthesia on renal haemodynamics in the rat was evaluated with radioactive microspheres 15 micrometer in diameter. 2. Both anaesthetic agents caused substantial decrements in total renal blood flow (sodium pentobarbital, -34%; Inactin, -24%) compared with unanaesthetized animals. 3. Measurements of renal function obtained in rats anaesthetized with either of these anaesthetic agents should be interpreted with caution.

SUMMARY Effects of gestation on volume homeostasis and renal function were studied in awake spontaneously hypertensive rats (SHR). Systolic blood pressure was similar to that of virgin littermates during most of SHR pregnancy but decreased near term (p < 0.005). Plasma renin activity was lower in SHR than in age-matched Wistar-Kyoto (WKY) rats (p < 0.001), but values were similar in gravid and nonpregnant animals from each strain. Renal renin content and lipid volume fractions of papillary interstitial granules were significantly greater in pregnant animals of each strain and those of the gravid WKY were also greater than both pregnant and virgin SHR. Saralasin had no effect on mean arterial pressure in gravid and virgin rats from either group. Plasma volume increased significantly near term in animals of both strains. Kidney weight, glomerular filtration rate (GFR), and renal blood flow were lower in SHR compared to WKY, and the hypertensive rats failed to demonstrate an increase in GFR during gestation, unlike the WKY. All SHR and pregnant WKY excreted infused sodium better than the virgin WKY. Also, regular Wistar animals excreted a salt load better than the virgin WKY. Finally, uterine blood flow, pup number and conceptus weight were similar in SHR and WKY. We conclude that pregnancy induces a decrease in blood pressure in SHR, and that angiotensin II does not seem to play an important role in maintaining blood pressure during gestation in either SHR or WKY. Despite a lower GFR and its failure to increase during pregnancy, renal sodium handling is not impaired in the SHR. The virgin WKY has a decreased ability to excrete sodium which is ameliorated during gestation. (Hypertension 5: 498-506, 1983) KEY WORDS • glomerular filtration rate • renal plasma flow • renal blood flow • renin-angiotensin system • plasma volume • sodium excretion • papillary interstitial cells R ESEARCH on hypertension during pregnancy has been hindered by the lack of suitable animal models. Okamoto and Aoki 1 have described a strain of rats (SHR) that develop hypertension spontaneously. The disease in these animals is said to resemble high blood pressure in humans in that they develop atherosclerosis and cardiovascular complications.2 Females of this strain of rats have a propensity to die of brain hemorrhage, which is of interest to us since intracranial bleeding is a major cause of death in pregnancy-associated hypertension in humans. The present study focuses on renal hemodynamics and volume homeostasis and compares the characteristics of hypertension in pregnant SHR to certain features of hypertensive disorders of human gestation.From the

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