Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Single intraperitoneal (ip) injections of angiotension II (ANG II) stimulated water intake for 60 min in a dose-related manner in the goldfish, Carassius auratus. Single ip injections of captopril (SQ14225), an angiotension I-converting enzyme (ACE) inhibitor, at lower doses (0.4 and 4.0 micrograms/fish), stimulated water intake for 60 min. This stimulation cannot be ascribed to an increase in levels of plasma ANG I, since ANG I (2.2 micrograms/fish) did not stimulate drinking in the presence of SQ14225 (two injections of 9.9 micrograms/fish). It is suggested that the elevated plasma ANG I concentration achieved after blockade of ACE was converted into ANG II approximately 50 min after SQ14225 injections (4.0 g/fish), when the injected SQ14225 was effectively metabolized. Thus, the newly elevated level of ANG II may have been responsible for the vigorous drinking. Higher doses of SQ14225 (40 and 200 microgram/fish) did not affect the water intake for 60 min, indicating that the rate of basal water intake is independent of the renin-angiotensin system in the goldfish.
Gen Comp Endocrinol 1988 Jan
PMID:Enhancement of water intake by captopril (SQ14225), an angiotensin I-converting enzyme inhibitor, in the goldfish, Carassius auratus. 328 72

Adult Rana temporaria, acclimated to tap water or hyperosmotic (0.9% NaCl saline) media, were injected with Acetazolamide, Frusemide, or Captopril, or were nephrectomized and injected with captopril. Saline-injected animals served as controls. Total water flux and drinking rates were determined by body weight changes and by the rate of accumulation of an environmental marker (phenol red) in the gut, respectively. Changes in plasma corticosteroids and ion concentrations were also assessed. Acetazolamide and frusemide produced hyponatraemia in tap water-acclimated animals, but induced increased aldosterone levels in frogs in both environments. Captopril reduced body weight and aldosterone levels of tap water frogs, but had no effect on plasma ion composition. Animals treated with captopril on immersion in saline had plasma hypoosmotic to their environment. Saline-acclimated frogs drank less environmental water than did those in tap water. Captopril, acetazolamide, and frusemide all stimulated drinking rates of saline-acclimated frogs; captopril, however, had no effect on the drinking rates of nephrectomized animals, indicating that the dipsogenic actions of this drug are probably reflected by inhibition of the renin-angiotensin system. In tap water animals, acetazolamide stimulated drinking, while frusemide stimulated integumental water uptake. No correlation was apparent between plasma aldosterone and corticosterone concentrations, or between changes in body weight and drinking rates. This suggests that there are independent mechanisms controlling aldosterone and corticosterone secretion, as well as integumentary and buccal uptake of water in R. temporaria.
Gen Comp Endocrinol 1987 Aug
PMID:Water uptake by Rana temporaria: effects of diuretics and the renin--angiotensin system, and nephrectomy. 330 52

1. Lasilactone, a new combination diuretic (furosemide 20 mg and spironolactone 50 mg) was evaluated in 30 patients with mild-to-moderate essential hypertension. Each patient received one capsule of lasilactone daily. 2. Significant changes in BP were observed 1 week after initiation of therapy and were sustained during the observation period of 1 year. 3. Supine and standing BP fell from 148.6 +/- 2.6/102.1 +/- 1.9 to 120.8 +/- 1.4/91.7 +/- 1.2 and from 154.4 +/- 2.1/106.1 +/- 1.6 to 125.7 +/- 2.2/90.7 +/- 1.5 mm Hg respectively. 4. There were no changes in the concentrations of plasma glucose, lipids, uric acid and potassium. On the other hand, levels of plasma renin activity rose from 0.69 +/- 0.06 to 3.95 +/- 0.47 ng/ml/hr and urinary aldosterone excretory rate increased from 9.6 +/- 1.6 to 42.8 +/- 4.2 micrograms/day. 5. This study suggests that addition of spironolactone to furosemide improves the hypotensive potency and minimizes the metabolic and electrolyte alterations of the latter.
Gen Pharmacol 1987
PMID:Efficacy and safety of lasilactone, a new combination diuretic, in essential hypertension. 331 70

Seasonal changes in heart rate, blood pressure, plasma and renal renin concentrations, plasma electrolyte concentrations, and osmolality were studied in freshwater turtles (Amyda japonica) exposed to the natural environment. Seasonal changes in heart rate and blood pressure showed a marked increase in summer and a decrease in winter, which correlated directly with that of an environmental temperature. Two peaks in plasma renin concentration were observed in November and May and correlated with the preparation for hibernation and arousal periods. Renal renin content exhibited a marked seasonal variation characterized mainly by an increase in summer, fall, and winter and a decrease in spring. Plasma sodium concentration and osmolality were the highest in summer, the lowest in winter, and intermediate during spring and fall. A change in plasma osmolality correlated closely with that of temperature. However, no marked seasonal variations in the concentrations of plasma potassium, chloride, and calcium were observed. On the basis of these data, we suggest that a circannual rhythm of renin concentration may be related to hibernation. We also suggest that seasonal changes in sodium concentration and osmolality relate closely to environmental temperature, although the mechanisms are not clear.
Gen Comp Endocrinol 1987 Sep
PMID:Circannual changes in renin concentration, plasma electrolytes, and osmolality in the freshwater turtle. 331 74

Circulating electrolytes (Na+, K+), plasma renin-like activity, testosterone, and testis morphology were investigated in early summer during the spermatogenic progressive phase in Vipera aspis subjected to sodium loading and sodium depletion. After sodium loading, plasma sodium and plasma testosterone levels were significantly elevated compared with those of controls, while plasma renin-like activity was depressed, spermiogenesis was increased, the epithelium lining the epididymis was very thick, and the Leydig cells were hypertrophied. After sodium depletion, plasma sodium and plasma testosterone levels were significantly depressed and plasma renin-like activity was significantly elevated. Spermiogenesis seemed to be slightly regressed: the epithelium lining the epididymis was very thin, and the lumen was devoid of spermatozoa. The Leydig cells were hardly visible. All the data strongly suggest that osmotic stress affects gonadal activity in the snake. V. aspis.
Gen Comp Endocrinol 1987 Dec
PMID:Osmotic stress, plasma renin activity, and spermatogenesis in Vipera aspis. 332 32

Noncompliance to fluid restrictions is remarkably common and difficult to treat in hemodialysis patients. Psychosocial variables have not been convincingly demonstrated to correlate with fluid noncompliance. Fluid overloading tends to begin early in the course of dialysis treatments and remains remarkably stable over time. This maladaptive behavior on the part of so many dialysis patients could be promoted by abnormalities in the renin-aldosterone-angiotensin system or other abnormalities in the homeostatic mechanisms that regulate water metabolism. Hypotheses related to addictive behavior and milieu variables are also discussed. Recommendations include using a nonmoralistic approach, flexibility in dialysis schedules, and psychological intervention at the onset of dialysis.
Gen Hosp Psychiatry 1988 Jul
PMID:Noncompliant hemodialysis patients. A biopsychosocial approach. 341 25

In the pithed Wistar rats Captopril (2 mg/kg) decreased the mean arterial pressure (MAP) 21%. Further injection of a specific antagonist decreased the vasoconstrictor action of vasopressin (aAVP, 10 micrograms/kg) an additional 6%. Reversal in the order of drug administration did not change these percentages. The osmotic stimulus evoked by the infusion of hypertonic saline (ClNa 9%, 0.018 ml/min, 2 hr) significantly increased MAP, this increase being almost totally reversed by the aAVP (10 micrograms/kg). These findings suggest a greater role of the renin-angiotensin system than of the vasopressin (AVP) in the maintenance of MAP in the pithed rat; AVP, moreover, can be released by means of an osmotic stimulus.
Gen Pharmacol 1986
PMID:Blood pressure control in pithed rat. 353 Aug 77

A serum potassium determination is usually recommended for new hypertensive patients as a screening test for primary aldosteronism and as a baseline for drug therapy. Since hypokalemia is not specific for aldosteronism, the authors assessed its use and limitations as a screening test in nine reported studies of 303 patients with aldosterone-producing adenomas (n = 252) or adrenal hyperplasia (n = 51). The optimal potassium cutoff level and the predictive ability of hypokalemia to detect aldosteronism were analyzed in a primary care setting with different diseases, test characteristics, and prevalences. Optimal screening for primary aldosteronism occurred at serum potassium less than 3.2 mEq/l in a primary care, low-prevalence population, and at higher potassium levels in higher-prevalence populations. Other screening tests, such as urinary aldosterone levels and plasma renin activity, showed lower individual test performance characteristics, but when combined were similar in performance to serum potassium measurement.
J Gen Intern Med
PMID:Screening for primary aldosteronism: hypokalemia in hypertensive patients. 354 Feb 35

Three putative pressor systems, the alpha-adrenergic system (AS), the renin angiotensin system (RAS), and the arginine vasotocin system (AVT-S), were studied for their roles in blood pressure regulation and their possible interactions in the rat snake. Ptyas korros. Norepinephrine (NE), angiotensin I (ANG I), and arginine vasotocin (AVT) increased the mean arterial pressure (MAP) of the snake while administration of phentolamine, an alpha-adrenergic antagonist, and captopril, an ANG-converting enzyme inhibitor, but not KBIV24, an AVT antagonist, decreased the MAP. Treatment with any combination of two of these antagonists/inhibitor invariably decreased the MAP. Treatment with the agonist of the remaining third system invariably returned the MAP to normal or above. Phentolamine and KBIV24 attenuated the vasopressor effect of ANG I. Phentolamine and captopril enhanced the vasopressor effect of AVT. The pressor effect of NE was not altered by KBIV24 and captopril. It was concluded that there were at least two pressor systems (AS and RAS) regulating the basal MAP in the snake. There was also interaction among the three systems which could affect the MAP.
Gen Comp Endocrinol 1986 Nov
PMID:Blood pressure homeostasis in the snake, Ptyas korros. 354 36

Effects of physostigmine on heart rate, mean arterial pressure (MAP), plasma renin concentration (PRC) and vasopressin (AVP) release were investigated in spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats. Physostigmine (100 micrograms/kg, i.a.) produced a greater and prolonged hypertensive response in the SHR than in the WKY. Heart rate was increased by physostigmine in SHR rats while it was unchanged in the WKY. PRC was unchanged or even slightly decreased in these animals when MAP was increased by physostigmine. An AVP pressor antagonist did not attenuate the pressor and cardiac effects of physostigmine in these animals. These data indicate that an impaired baroreflex mechanism or a different mode of sympathetic neuronal activation by physostigmine through the central mechanism appears to be contributory, at least in part, to the enhanced pressor responsiveness in the SHR. The renin-angiotensin system and AVP do not appear to be involved in the enhanced pressor responsiveness to physostigmine in SHR rats.
Gen Pharmacol 1987
PMID:Possible involvement of an impaired baroreflex mechanism but not the renin-angiotensin system and vasopressin in the enhanced pressor responsiveness to physostigmine in spontaneously hypertensive rats. 355 64


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