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C Garutti

Publications and source records attributed to C Garutti.

At least 19 recordsLinked to original sources

Interactions between the renin-angiotensin system and prostanoids in modulating renal function in potassium-depleted healthy women.

Plasma renin activity (PRA) and urinary aldosterone excretion were determined in healthy women with normal potassium balance (N, n = 20) or experimental potassium depletion (KD). KD was induced by natriuretic treatment--associated with replacement of net NaCl and water losses--and low dietary potassium intake (< or = 10 mmol/d). By using different depletion patterns, three groups were obtained with cumulative potassium deficits (mean +/- SEM) of 160 +/- 43 (KD1, n = 8), 198 +/- 22 (KD2, n = 6) and 215 +/- 54 mmol (KD3, n = 6). The renal function by the clearance (cl.) method and urinary concentrations of prostaglandin E2 (PGE2), 6-keto-PGF1 alpha (6KPGF), and thromboxane B2 (TXB2) by the RIA method were estimated during hypotonic polyuria (oral water load) and subsequent moderate antidiuresis induced by low-dose infusion of lysine-8-vasopressin (LVP). 1. In all KD groups the depletion treatment significantly reduced both potassium plasma concentration (PK) and urinary potassium excretion while it increased basal PRA; the basal urinary aldosterone excretion was not significantly different from normokalemic controls. In the KD3 vs KD1 group the P kappa value was significantly lower. 2. In both KD2 and KD3 groups as compared to the N group, several hypokalemic-like renal dysfunctions--absent in the KD1 group--occurred. Particularly, in the KD2 + KD3 vs N group the renal ability in both urine diluting (water load) and concentrating (LVP infusion) was significantly impaired.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha

Experience with psoriasis in a psychosomatic dermatology clinic.

We studied 179 psoriatic patients by semistructured colloquia and psychometric tests and determined their cutaneous psycho-neurophysiological profiles by biofeedback methods. The Paykel scale for stressful events showed that 72% of psoriatics had experienced significant stressful events about one month before the appearance of the psoriasis. The Zung test for anxiety and depression showed a high level of anxiety in the psoriatic patients. 64% of the patients who were treated by BFBtraining had a decrease in their PASI index for severity and the extent of the disease and also fewer recurrences at the one-year follow-up. The results of the World Experience Inventory indicated difficulties related to body image and to relationships with others. Psoriasis influenced the sexuality of the patients. It is always difficult when one is afflicted by ill health to enjoy life and the general scores of SWL (Satisfaction with Life), were significantly lower than those of a control group.

Adult

Studies on renal function in healthy women with different degrees of induced potassium depletion. 2). Patterns of hypokalemic renal dysfunction.

In order to investigate the renal functional effects of potassium depletion (KD) we have submitted 20 healthy women to different potassium depletive treatments by dietary and pharmacological means. By changing these treatments we have obtained three KD groups with cumulative potassium deficit of 160 +/- 43 (KD1, n = 8), 198 +/- 22 (KD2, n = 6) and 214 +/- 54 mmol (KD3, n = 6). Another 20 subjects were also studied as controls in normal potassium balance (N group). In all subjects the renal function has been evaluated by clearance (cl.) technique both during induced hypotonic polyuria and subsequent moderate antidiuresis induced by low dose infusion of lysine-8-vasopressin (LVP). A renal dysfunction occurred in differences between these two groups, they have been pooled in a single KD2 + KD3 group. In this group as compared to N the following renal dysfunctions were observed during hypotonic polyuria: a) reduction in creatinine cl. (in absence of significant differences in mean arterial pressure); b) inhibition of the fractional reabsorption of chloride by diluting segments; c) depression of the diuretic response to water load. Moreover in KD the LVP was less effective in reducing the creatinine cl. while it became effective in reducing the fractional excretions of NaCl. These findings indicate that the degree of KD reached in the KD2 + KD3 group was adequate to induce a renal dysfunction similar to that occurring in conditions of chronic hypokalemia. It is probable that hypokalemia by itself along with changes of both prostaglandin and angiotensin renal systems are involved in this renal dysfunction.

Blood Pressure

Studies on renal function in healthy women with different degrees of induced potassium depletion. 3) Effective roles of prostanoids and angiotensin II in hypokalemic renal dysfunction.

By using two similar dietary and pharmacological patterns of potassium depletive treatment, two experimental groups--KD2 (n = 6) and KD3 (n = 6)--with cumulative potassium deficit not significantly different, were obtained. The basal values of plasma potassium concentration and PRA, as well as the expression of renal hypokalemic dysfunction were not significantly different. Paired studies in the absence and presence of indomethacin (KD2 group) or enalapril (KD3 group) were performed. The aim of the research was evaluation of the effective roles of prostanoid and angiotensin (AT) II systems in renal hypokalemic dysfunction. The results show that: 1) AT II and cortical vasodilating prostanoids exerted opposite effects on the preglomerular arteriolar tone; 2) medullary prostanoids antagonized the vasopressin effects. Therefore, in potassium depletion the decreased synthesis of cortical and medullary prostanoids, in the face of the increased generation of AT II, contributed to reducing the glomerular filtration rate and facilitate the expression of vasopressin action. These components of the renal hypokalemic dysfunction probably exert a protective role with regard to the urinary chloride and potassium losses.

Angiotensin II

Effects of experimental potassium depletion on renal function and urinary prostanoid excretion in normal women during hypotonic polyuria.

During hypotonic polyuria renal function studies by the clearance (cl.) method, and urinary PGE2, 6-keto-PGF1 alpha and TxB2 determinations were performed on 14 healthy women in normal potassium balance (N) and 14 healthy women in sustained potassium depletion (KD) induced by low dietary potassium intake (less than or equal to 10 mmol day-1) and natriuretic treatment. By using different depletive patterns, two groups with estimated cumulative potassium deficits of 160 +/- 43 mmol (KD1, n = 8) and 198 +/- 22 mmol (KD2, n = 6), respectively, were obtained. (1) In both the KD1 and KD2 groups as compared to normal potassium balance (N), plasma potassium concentration and urinary potassium excretion were significantly lower; plasma renin activity was significantly higher. (2) Only in KD2 did significant changes appear in renal function and urinary prostanoid excretions. Besides a decrease in creatinine cl. and the urinary flow rate, an increase in fractional chloride excretion and a reduction in distal fractional chloride reabsorption were manifest. The plasma chloride concentration was reduced too. Urinary prostanoid excretions were significantly (6-keto-PGF1 alpha, TxB2) or tendentially (PGE2) lower. (3) Indomethacin treatment resulted in changes in mean arterial pressure (increase) and creatinine cl. (decrease) which were not significantly different in normal potassium balance and KD groups. Only in KD2 did the drug significantly reduce the fractional salt and water excretions and the fractional sodium and chloride deliveries to the diluting segments. However, indomethacin was unable to correct the inhibition of distal fractional chloride reabsorption. Therefore, the potassium depletion attained in the KD2 group was efficacious in depressing renal prostanoid synthesis. This fact, in the presence of high levels of angiotensin II, induced a reduction of the glomerular filtration rate thus contributing to renal ability to retain chloride and potassium.

Adult

[Selective inhibitory effects of experimental potassium depletion on urinary excretion of prostanoids and their possible functional significance].

The urinary concentrations of prostaglandins(PG) E2, 6-keto-PGF1 alpha (6KPGF) and thromboxane (Tx) B2 were measured by RIA method during both hypotonic polyuria (oral water load) and subsequent antidiuresis (low-dose infusion of lysine-8-vasopressin). The study was performed on healthy women either in normal potassium balance (N, n = 14) or sustained potassium depletion (D3, n = 6). Potassium depletion (KD) was induced by low potassium dietary intake (less than or equal to 10 mmol/d) and natriuretic treatment over a period of 8 days; the net losses of NaCl and H2O were replaced; the cumulative potassium deficit was 198 +/- 22 mmol. Further studies were performed after indomethacin treatment in both experimental conditions. 1) As compared to normal potassium balance in KD group the urinary prostanoid excretions were reduced even in absence of significant differences in urinary flow rate. The urinary excretion of 6KPGF was more impaired than that of TxB2 in both polyuria and antidiuresis. 2) Indomethacin inhibited the urinary prostanoid excretions in normal potassium balance and KD groups. The urinary excretion of PGE2 was more impaired than that of both 6KPGF and TxB2.

Adult

Antagonistic effects of sulpiride--racemic and enantiomers--on renal response to low-dose dopamine infusion in normal women.

In healthy women during moderate hydrosaline retention we have evaluated the antagonistic effects of sulpiride--enantiomers and racemic--on the renal action of a low-dose dopamine (DA) infusion (0.1 microgram/kg/min). The studies were performed, in hypotonic polyuria, by the clearance (C1) method in (1) hydrosaline retention (n = 23), (2) retention + dl-sulpiride (n = 8), (3) retention + d-sulpiride and (4) retention + l-sulpiride (in the latter two cases n = 7 subjects submitted to paired studies). Hydrosaline retention was induced by deoxycorticosterone acetate treatment. A common pattern of sulpiride treatment was applied. The DA renal hyperemia is abolished by l-sulpiride while it is transitorily attenuated by d-sulpiride. In both conditions 3 and 4 the increase in glomerular filtration rate, the inhibition of fractional isosmotic sodium reabsorption and the increase in urinary sodium excretion--induced by DA in condition 1--are suppressed. On the contrary, DA inhibition of fractional anisosmotic sodium reabsorption is not affected by sulpiride. The data indicate that DA renal hyperemia results from the action of DA on DA2 receptors; the DA inhibition of sodium transport by the diluting segments does not appear to be mediated by typical DA receptors.

Adult

[Renal function in experimental potassium depletion. I. Effects of lysine-8-vasopressin in hypotonic polyuria].

Renal function has been studied by the clearance (cl.) method during hypotonic polyuria--four 15-min cl. periods--and successive antidiuresis--two 60-min cl. periods (A1, A2)--induced by lysine-8-vasopressin (LVP), 5 mU in bolus followed by infusion at a rate of 0.04 mU/min. The endogenous creatinine cl. (Cc) and the osmotic cls. (Cosm, CH2O) were determined by the usual methods as well as the absolute and fractional urinary excretions of water, sodium, chloride and potassium. The urinary concentrations of PGE2, 6-keto-PGF1 alpha and TxB2 were determined by the RIA method. This study protocol has been applied to 28 healthy women either in normal potassium balance (N, n = 14) or after potassium depletion (KD) induced by low potassium dietary intake (less than or equal to 10 meq/d) plus natriuretic treatment according to two different time patterns: two KD groups were obtained with potassium cumulative deficit of 160 +/- 43 (D2, n = 8) and 198 +/- 22 meq (D3, n = 6). The early % effects of LVP, i.e. (A1-P)% of P (mean polyuria), were significantly different only in D3 as compared to N. Precisely, the LVP-effect to reduce Cc was blunted; moreover a LVP-effect to reduce renal sodium and chloride fractional excretions and a tendentiously enhanced LVP-effect to reduce water fractional excretion were observed. These tubular effects are likely related to the inhibited renal synthesis of prostanoids in the D3 group.

6-Ketoprostaglandin F1 alpha

[Renal function in experimental potassium depletion. II. Indomethacin and effects of lysine-8-vasopressin in hypotonic polyuria].

Renal function has been studied by the clearance (cl.) method during hypotonic polyuria--four 15-min cl. periods--and successive antidiuresis--two 60-min cl. periods (A1, A2)--induced by lysine-8-vasopressin (LVP), 5 mU in bolus followed by infusion at a rate of 0.04 mU/min. The endogenous creatinine cl. (Cc) and the osmotic cls. (Cosm, CH2O) were determined by the usual methods as well as the absolute and fractional urinary excretions of water, sodium, chloride and potassium. The urinary concentrations of PGE2, 6-keto-PGF1 alpha and TxB2 were determined by the RIA method. This study protocol has been applied to 20 healthy women submitted to paired functional explorations in both the absence and presence of indomethacin (100 mg i.m.); the drug effects have been evaluated in both normal potassium balance (N2, n = 6) and in two groups of potassium depletion (KD) with potassium cumulative deficit of 160 +/- 43 (D2, n = 8) and 198 +/- 22 meq (D3, n = 6), respectively. As regards the early % effects of LVP, i.e. (A1-P)% of P (mean polyuria), the inhibition of prostanoid synthesis with indomethacin produced significant changes: 1) an enhanced reduction in renal chloride excretion in all experimental groups; 2) a reduction in renal sodium and chloride fractional excretions in both KD groups; 3) an enhanced antidiuretic effect in D3 only, i.e. in the experimental condition with inhibition of prostanoid renal synthesis present during the control study.

6-Ketoprostaglandin F1 alpha

[Further research on the role of prostanoids in controlling renal function in humans in normal potassium balance and acute experimental potassium depletion. I: Studies of normal potassium balance. Effects of indomethacin].

The renal function was studied by clearance (cl.) method during hypotonic polyuria (oral water load followed by 5% dextrose solution infusion) and successive relative antidiuresis induced by lysine-8-vasopressin (LVP) administration (5 microU in bolo followed by continuous infusion at a rate of 0.04 microU/min). Four 15 min and two 60 min clearance (cl.) periods were performed during hypotonic polyuria and antidiuresis, respectively. Glomerular filtration rate was estimated by creatinine cl.; the osmotic cl. (Cosm, CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary PGE2, 6-keto-PGF1 alpha and TxB2 concentrations were determined by RIA method. Fourteen healthy women submitted to a normal sodium and potassium daily intake were studied; in 6 of them paired studies in absence and in presence of indomethacin (100 mg, i.m.), respectively, were performed. LVP induced a significant reduction of creatinine cl., urinary flow rate and of prostanoid excretion. In hypotonic polyuria, indomethacin significantly reduced the creatinine cl. and the diuretic response to the water load; moreover the urinary PGE2 and 6-keto-PGF1 alpha excretions were significantly lower (85.6 +/- 1.9% and 37.7 +/- 3.2%) while the reduction of urinary TxB2 excretion was not significant (34.4 +/- 13%). Indomethacin did not affect significantly the LVP renal effects in normal potassium balance.

Dinoprostone

[Further research on the role of prostanoids in controlling renal function in humans in normal potassium balance and acute experimental potassium depletion. II: Studies of potassium depletion].

The renal function was evaluated by clearance (cl.) method during hypotonic polyuria and successive relative antidiuresis induced by lysine-8-vasopressin (LVP) administration. Four 15 min and two 60 min cl. periods were performed during hypotonic polyuria and antidiuresis, respectively. Glomerular filtration rate was estimated by creatinine cl.; the osmotic cl. (Cosm'CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary PGE2, 6-keto-(-)PGF1 alpha and TxB2 concentrations were determined by RIA method. The study protocol was applied on 22 healthy women in acute potassium depletion obtained by natriuretic treatment combined with replacement on quantitative basis of net salt and water urinary losses either in normal potassium diet intake (50 meq/d) or in a low one (less than or equal to 10 meq/d). In Group D3 (n = 6) in the presence of a greater potassium cumulative deficit (198.4 +/- 22.2 meq), as compared to normal potassium balance, a significant reduction of kaliemia and a significant increase of PRA were present. During hypotonic poliuria, besides a marked renal potassium conservation, a significant decrease of creatinine cl., fractional chloride reabsorption (apparently at the diluting segments) and of urinary 6KPGF and TxB2 excretions, were observed. Urinary PGE2 excretion was n.s. reduced.

Acute Disease

[Further research on the role of prostanoids in controlling renal function in humans in normal potassium balance and acute experimental potassium depletion. III: Effects of indomethacin in potassium depletion].

The renal function was evaluated by clearance (cl.) method during hypotonic polyuria and successive relative antidiuresis induced by lysine-8-vasopressin administration. Four 15 min and two 60 min cl. periods were performed in hypotonic polyuria and antidiuresis, respectively. Glomerular filtration rate was estimated by creatinine cl., the osmotic cl. (Cosm' CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary PGE2, 6-keto-PGF1 alpha and TxB2 excretions were determined by RIA method. The study protocol was applied on 14 healthy women in acute potassium depletion, treated with indomethacin (100 mg i.m. at the end of the oral water load). In Group D3 (n = 6) in the presence of a greater potassium cumulative deficit (198.4 +/- 22.2 meq), in hypotonic polyuria, indomethacin induces significant effects as an increase of fractional hydro-electrolytic reabsorptions and as a decrease of urinary prostanoid excretion. The indomethacin tubular action in potassium depletion differs significantly from that observed in normal potassium balance.

Acute Disease

[Role of prostanoids in the control of renal function in normal potassium balance and in acute experimental potassium depletion. 4. Relation of extrarenal parameters, renal function parameters and urinary excretion of prostanoids].

The renal function has been evaluated by clearance (cl.) method during hypotonic polyuria and successive moderate antidiuresis induced by a low dose of lysine-8-vasopressin; four 15 min and two 60 min cl. periods were performed, respectively. Glomerular filtration rate was estimated by creatinine cl.; the osmotic cl. (Cosm, CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary concentrations of PGE2, 6-keto-PGF1 alpha (6KPGF) and TxB2 were measured by RIA. The study protocol was applied in normal potassium balance and experimental potassium balance (KD), both in absence and presence of indomethacin. In KD groups with a potassium cumulative deficit of 198.4 +/- 22.2 meq (D3; n = 6) during polyuria significant correlations are consistent with the hypothesis that the lower the plasma potassium concentration is the higher the urinary chloride excretion and the inhibition of distal fractional chloride reabsorption. Moreover, by utilizing the polyuria and antidiuresis data pool, the effects of urine flow rate changes on PGE2 and 6KPGF urinary excretions are blunted as compared to normal potassium balance (n = 14). After indomethacin treatment (D3.I) the following functional relationships are disclosed: a) the lower the kaliemia is the lower the urinary chloride and potassium excretions and the higher the fractional isosmotic reabsorption; b) the lower the urinary potassium excretion is the lower the urinary chloride excretion. In both D3 and D3.I experimental groups the positive correlation between urinary chloride excretion and urinary potassium excretion is significant.

6-Ketoprostaglandin F1 alpha

Effects of extracellular fluid volume changes on renal response to low-dose dopamine infusion in normal women.

Dopamine (DA) i.v. infused in a low dose (0.1 microgram/kg/min) in healthy women during sustained hypotonic polyuria, produced different renal functional effects as variations in extracellular fluid volume occurred. (1) In hydro-saline retention (n = 23), induced by desoxycorticosterone acetate treatment, DA produced typical vasodilator and hydro-natriuretic effects (Goldberg, 1972). (2) In hydro-saline depletion (n = 19), induced by diuretic treatment and low dietary sodium intake, DA lost its vasodilator and natriuretic efficacy, manifesting, on the other hand, renal sodium conserving effects mainly dependent on the increase in distal sodium reabsorption and a trend towards afferent arteriolar vasoconstriction. (3) Treatment with prazosin (n = 9) or propranolol (n = 9) in hydro-saline depletion, was efficacious in partly restoring the typical vasodilator and natriuretic effects of DA. Thus, in hydro-saline depletion, DA produced sympathomimetic effects which were sufficiently intense to outweigh those due to activation of specific DA renal receptors.

Adult