Circadian Variations of Plasma Renin Activity and Plasma Osmolality in Various Physiological and Pathological States

Minai, Koji

doi:10.1620/tjem.114.159

Cited by 6 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such a mechanism may not have any physiological significance in the daily regulation of insulin secretion but it may very well be of physiological importance in regulation of renin release in vivo. The reported inverse relationship between circadian rhythms of plasma osmolality (Minai, 1974) would seem compatible with such a regulatory mechanism, which also might be responsible for the increase in plasma renin seen after anaesthesia and certain diuretics. As was proposed previously (Frederiksen et al 1975) the juxtaglomerular-cell could function as a systemic osmometer while at the same time volumesecretion coupling could underlie both the baroreceptor and chemoreceptor STUDIES ON RENIN RELEASE concepts of renin release and account for a feed-back response via the macula densa.…”

Section: Discussionmentioning

confidence: 71%

Studies on renin release from isolated superfused glomeruli: effects of temperature, urea, ouabain and ethacrynic acid.

Baumbach¹,

Leyssac²,

Skinner³

1976

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. The effects of different energy substrates, of low temperature, of urea, and of ouabain and ethacrynic acid were studied on the rate of renin release from viable juxtaglomerular cells during superfusion of isolated rat glomeruli.2. Neither lactate nor glutamate altered renin release rate from that observed using glucose as the sole energy substrate. Succinate 10 mM elevated release transiently but did not influence the release caused by reductions in osmolality through lowering sucrose concentration.3. Peak renin release was more prolonged and returned more slowly to control following reductions in osmolality in phosphate-Ringer than in bicarbonate-Ringer.4. At 370 C, the peak of renin release induced by hypo-osmolality was smaller and delayed, and returned earlier to control than at 300 C.5. Reduction in temperature from 30 to 40 C resulted in a 32-fold increase in basal release rate. At 40 C a 20 m-osmole/kg reduction in tonicity caused an additional 2*5-fold increase in release rate.6. Increasing superfusate osmolality with urea did not affect basal renin release but 100 mm urea suppressed the releasing effect of a 15 mM reduction in NaCl concentration.7. Ouabain (10-4M) caused a small (33+9 %, P < 0.025) transient increase in renin release. Ethacrynic acid (10-3 M) provoked a progressive increase in release reaching 100 + 15 % above control within 50 min. In the presence of both inhibitors the release provoked by hyposmolality was prolonged.8. It is concluded that renin release in vitro is a function of actively regulated cell volume and it is proposed that a similar mechanism could * Visiting scientist, from the University of Melbourne, Australia.

show abstract

Section: Discussionmentioning

confidence: 71%

Studies on renin release from isolated superfused glomeruli: effects of temperature, urea, ouabain and ethacrynic acid.

Baumbach¹,

Leyssac²,

Skinner³

1976

The Journal of Physiology

View full text Add to dashboard Cite

show abstract

“…Minai (15) has recently demonstrated a statistically significant re ciprocal correlation between the circadian variations of PRA and plasma os molality in normal subjects kept at bed rest. Since vasopressin secretion would tend to reduce plasma osmolality, this would make it possible that plasma AVP would have a similar circadian rhythm to that of renin and angiotensin.…”

Section: Discussionmentioning

confidence: 97%

Plasma Vasopressin Variation and Renin Activity in Normal Active Humans

Katz¹,

Smith²,

Lock³

et al. 1979

Horm Res

View full text Add to dashboard Cite

Plasma concentrations of vasopressin and plasma renin activity were measured every 30 min for 24 h in 5 normal active humans, in 1 normal woman confined to bed (except for brief periods up to the bathroom), in 2 active patients with primary aldosteronism and in 1 patient with low-renin hypertension. Plasma vasopressin varied markedly over the day and night in a pattern suggesting episodic secretion of the hormone in the normal subjects. Assumption of upright posture was accompanied by a rise in plasma levels from undetectable to 20–50 pg/ml. Episodic secretion, however, also occurred during bed rest and sleep. In contrast, patients with primary aldosteronism and low-renin hypertension had plasma vasopressin levels considerably lower than the normals, and their profiles of plasma concentration lacked the peaks seen in normals. In the normals, although vasopressin and renin secretion often coincided, only 2 of 6 studies showed a significant correlation between the plasma levels of the two hormones. This study, therefore, shows that vasopressin is secreted periodically in normal humans, that upright posture is an important modulator of secretory activity and that the renin-angiotensin system may or may not influence the pattern of secretion. In addition, it underlines the necessity of recumbency in establishing the existence of a circadian rhythm of plasma vasopressin levels.

show abstract