Kiinische Wochenschrift
Klin. Wschr. 56, 135-138 (1978)
© Springer-Verlag 1978
Non-Interaction of Spironolactone Medication and Cortisol Metabolism in Man* U. Abshagen**, S. Sp6rl and M. L'age Department of Internal Medicine and Department of Clinical Pharmacology, Klinikum Steglitz, Freie Universit~t Berlin
Normales Plasmacortisol unter Spironolaktonbehandlung Zusammenfassung. Bei 5 gesunden Probanden und bei 5 Patienten mit dekompensierten Lebererkrankungen wurden die Konzentrationen von Cortisol und yon Canrenon und Canrenoat-K im Plasma nach jeweils einer Einzeldosis von 7 mg Spironolakton/kg mit und ohne 12t/igiger Vorbehandlung mit Spironolakton tiberjeweils 4 Tage verfolgt. Die Bestimmung der Spironolaktonmetabolite erfolgte fluorimetrisch. Das Cortisol im Plasma wurde mit einem hochspezifischen Radioimmunoassay mit vorgeschalteter chromatographischer Trennung bestimmt. Als Ergebnis zeigte sich keinerlei Beeinflussung der Cortisolplasmaspiegel und der circadianen Rhythmik durch hochdosierte oder 1/ingerfristige Spironolaktonmedikation bei Gesunden und Leberkranken. SchliisselwiJrter: S p i r o n o l a k t o n - Canrenon - Canrenoat-K - Plasmacortisol - Normalprobanden Leberkranke.
Summary. In 5 healthy subjects and in 5 patients with decompensated liver diseases, the concentrations of cortisoL canrenone and canrenoate-K were determined after single doses and after a long-term treatment with spironolactone. The concentrations of the metabolites of spironolactone were determined fluorimetrically, those of cortisol by a highly specific radioimmunoassay with previous chromatographic separation. As a result, non-interaction between spironolactone medication and cortisol metabolism, even at high * The study was supported by grants of the Deutsche Forschungsgemeinschaft to Dr. Abshagen (Ab 28/3) and Dr. L'age. ** Offprint requests to: Priv. Doz. Dr. U. Abshagen (address see page 138)
dose and long-term treatment conditions, was established neither in normal test subjects nor in patients with liver failure.
Key words: Canrenone - Cenrenoate-potassium Spironolactone - Normals - Liver failure - Cortisol plasma levels.
Introduction The possible influence of spironolactone medication on plasma levels of cortisol is not definitely ascertained up to now. In 1970 in several reports different authors (Lurie; Wood et al.) reported under spironolactone medication increased plasma levels of cortisol. The latter were determined using the Mattingly (1962) technique. This increase, however, was due to crossinterference of spironolactone metabolites in the fluorimetric assay ofcortisol as was demonstrated already by these authors and later also by Dumlao et al. (1973). Inhibition of hydroxylation steps during the synthesis of cortisol on the other hand, were described by several authors in vitro. In rat adrenal slices Erbler (1973) demonstrated a decreased formation of corticosterone during incubation with the spironolactone metabolite canrenone and postulated a competitive inhibition of 1lfl-hydroxylases. Greiner et al. (1976) observed a diminished cortisol production in adrenal slices of guinea pigs pretreated with spironolactone. Cheng et al. (1976) also demonstrated a specific binding of spironolactone, canrenone and canrenoate potassium to cytochrome P450 of bovine and human adrenal microsomes with subsequent decrease of 11 flhydroxylase activity. Furthermore, in cortisol producing species-dog and guinea p i g - M e n a r d et al. (1974) reported a reduction of 17e-hydroxylase-activ-
136
U. Abshagen et al. : Spironolactone and Plasma Cortisol
Table
1. Cross-reactions of the cortisol antibody (Vecsei et al., 1972) with spironolactone, canrenone, canrenoate-potassium and 7~-thiomethylspirolactone. Calculation according to Abraham (1969) Substrate
Cross reactions (%)
Cortisol Spironolactone Canrenone Canrenoate-K 7~-thiOmethyl-spirolactone
100.000 0.016 0.097 0.006 0.051
and repetitive doses of spironolactone, under simultaneous monitoring of their plasma levels of cortisol, canrenone and canrenoate-potassium.
Methods and Materials Procedure
ity in adrenal microsomes of spironolactone pretreated animals and discussed a possible decreased formation also in vivo of all steroids which were hydroxylated in 17e-position such as cortisol. Since spironolactone is a potent enzyme inducer in rats and mice, an enhanced degradation of cortisol, for example by increased 6/~-hydroxylation, also seems to be possible. Thus the question arises whether spironolactone medication influences the cortisot metabolism under therapeutical conditions in man. Study was so undertaken in normal subjects and in patients with decompensated liver diseases who were administered single
pg/I 700
200
Analytics The determinations of canrenone and canrenoate-potassium were done using a fluorescence assay according to Sadbe et al. (1972). The calculations were based upon own standard curves. The determination of cortisol in plasma was performed according to a modified method of Vecsei et al. (1972), using the antibody of these authors. Only minimal cross-reactions with spironolactone
plasma
%°
soo ~1~2b-'~ ! ~o,,,. 400
5 healthy young males and 5 male patients each with decompensated liver diseases (i. e. formation ofascites) received 7 mg slNronolactone/kg as a single close at 8 a.m, Venous blood was drawn before and 0.25, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48, 60, 72, 84, 96 h after administration for determination of cortisol levers in plasma and of concentrations of canrenone and canrenoatepotassium. After this time 7 mg spironolactone/kg were given to the subjects daily in three divided doses for 12 days and then the procedure as described was performed for a second time. Clinical data of the patients and details about spironolactone disposition in these cases are published elsewhere (Abshagen et al., t977b).
normals patients e~e canrenone &~A
,d'i ~".,,
......
canrenoate~K = .....
N;:-"'.::..,.,., ~'"~"
a . , . t=~,~e,
~,,,~....;2
8 1'2
2~4
36
° . . . . =.,~,= . . . . . . . . . . . . . . . .
48
60
72
84
~6 h
Fig. 1. Concentrations of canrenone and canrenoate-potassium in plasma of normal subjects and of patients with decompensated liver diseases after the first single dose of 7 mg spironolactone/kg p. o, ; mean values (n = 5) - t o p - . Concentrations of cortisol in plasma of normal subjects • - - - • and patients with decompensated liver disease • • after the first single dose of 7 mg spironolactone/kg p.o. 5c+ s~ (n = 5). Dashed area: range of normal values (8 a. m.). - b o t t o m -
cortisol -concentration ~g/l p l a s m a
8 12
24
36
48
60
72
84
96
U. Abshagen et al. : Spironolactone and Plasma Cortisol or its metabolites canrenone, canrenoate-potassium and 7c~-thiomethylspirolactone could be established (Table 1). Since, the concentrations of these metabolites in plasma were however by far higher than those of cortisol (Fig. 1), an extraction of the plasma° firstly with CC1, and secondly by means of CH~Cla with subsequent purification and separation by paper chromatography (mobile phase: 80 v/v benzene: 20 v/v hexane=4:l; stationary phase: 80v/v methanol: 20v/v H20=4:1) was furthermore introduced nto the assay before the radioimmunological procedure was undertaken. By this means a complete separation of cortisol from endogenous steroids as well as from spironolactone and its metabolites was achieved. The assay was thus highly specific in measuring cortisot.
Results and Discussion O n top of figure 1 the concentrations o f canrenone and canrenoate-potassium in plasma are shown during four days after the first single administration of 7 m g spironolactone/kg. Plasma levels o f canrenone and cancenoate-potassium peaked approximately 2 and 8 h after administration, respectively, with subsequent m o n o e x p o n e n t i a l decline. The half lives for canreno~e were 1.49_+0.15 and 1.59_+0.13, those of canrenoate potassium 1.36±0.13 and 1.90-t_-0.20 in normals and patients, respectively. After 12 days treatment with spironolactone, the mean m a x i m u m concentrations following the second single dose of spironolactone a m o u n t e d to 1.01_+0.28 lag/ml and 1.04 + 0.21 gg/ml for canrenone and 0.56+_ 0.06 I,tg/ml and 0.97+_0.29 gg/ml for canrenoate-potassium in normals and patients, respectively. The concentrations d r o p p e d d o w n with half lives which were only insignificantly different as c o m p a r e d to the first part of the study. These long half lives gave rise to cumulation o f the spironolactone metabolites in man. Since in rats, the half tiles of the metabolites were in the range o f 2-3 h only (Sadie et al., 1974), the concentrations attained in the course of the 12 days treatment in m a n were even higher than those determined in rats after the usual pretreatment procedure with by far higher doses o f spironolactone (100 m g / k g b. i.d. for 3 days) (Abshagen, 1977a). Thus, the experimental conditions with respect to the effective concentrations o f spironolactone metabolites at the site of the adrenals o f m a n are c o m p a r a b l e under in vivo conditions to those of experimental animals in spite of considerable differences in dosage. Regarding the cortisol levels in plasma at the beginning of the investigation just before administration of the drug, the respective concentrations in patients were distiflctly higher as c o m p a r e d with n o r m a l subjects, for n o obvious reason, Later on the cortisol levels in healthy subjects were n o longer different f r o m those o f patients with d e c o m p e n s a t e d liver dis-
137 eases. F u r t h e r m o r e , no influence at all o f the drug on the actual cortisol levels nor on the circadian r h y t h m could be denaonstrated. In addition, the cortisol levels in plasma and their circadian kinetics were unaltered after 12 days' treatment with 7 m g spironolactone daily. It can thus be concluded that b o t h in patients with n o r m a l and with pathological liver function, the cortisol metabolism is not impaired even by high dose and long-term treatment with spironolactone. Other conditions m a y be true for the synthesis chain leading to aldosterone where increased levels of 11-deoxycorticosterone and corticosterone were observed which were a c c o m p a n i e d by a decrease o f aldosterone concentrations in plasma o f short duration (Abshagen et al., 1976b, 1977c). lit might be assumed therefore that spironolactone acts in a different m a n n e r u p o n the hydroxylases of the z o n a glomerulosa as c o m pared to those o f the z o n a fasciculata o f h u m a n adrenals in vivo. Spironolactone, canrenone and canrenoate-potassium, cryst., purriss. were a generous gift of Boehringer, Mannheim (Germany). 7¢~-thiomethyl-spirolactone cryst., purriss, was provided by Searle & Co. (Chicago)
References 1. Abraham, G.E.: Solid-phase radioimmunoassay of estradiol17/~. J. Clin. Endocrinol. Metab. 29, 866 (1969) 2. Abshagen, U., Rennekamp, H., Luszpinski, G.: Pharmacokinetics of spironolactone in man. Naunyn Schmiedeberg's Arch. Pharamcol. 296, 37~45 (1976a) 3. Abshagen, U., Sp6rl, S., Sch6nesh6fer, M., L'age, M., Rennekamp, H., Oelkers, W. : Influence of spironolactone endogenous steroid metabolism in man, Clin. Sci. Mol. Med. 51, 307s- 310s (1976b) 4. Abshagen, U, :/?-methyldigoxin disposition during spironolactone treatment. In: International Symposium on Cardiac Glycosides, Bodem, G., Dengler, H.J. (Ed.), Springer-Verlag, Berlin Heidelberg New York 1977a in press 5. Abshagen, U., Rennekamp, H., Luszpinski, G.: Disposition kinetics of spironolactone in hepatic failure after single doses and prolonged treatment. Europ. J. Clin. Pharmacol. 11, 169 176 (1977b) 6. Abshagen, U., Sp6rl, S., SchSnesh6fer, M., Oelkers, W.: Increased plasma ll-deoxycorticosterone during spironolactone medication. J. Endocrin. Metab. 44, 1190-1193 (1977c) 7. Cheng, S.C., Suzuki, K., SadSe, W., Harding, B.: Effects of spironolactone, canrenone and canrenoate-K on cytochrome P 450, and 11/3- and 18-hydroxylation in bovine and human adrenal cortical mitochondria. Endocrinology 99, 1097-1t06 (1976) 8. Dunlao, J.S., Kannan, Ch., Krauss, Th., Brooks, M.H. : Spironolactone and plasma cortisoL Clin. PharmacoL Ther. 14, 992-994 (1973) 9. Erbler, H.C.: On the mechanism of the inhibitory action of the spironolactone SC 9376 (aldadiene) on the production of corticosteroids in rat adrenals in vitro. Naunyn-Schmiedeberg's Arch. Pharmacol. 277, 139-149 (1973) 10. Greiner, J.W., Kramer, R.E., Jarrell, J., Colby, tt.D. : Mechanism of action of spironolactone on adrenocorticai function in guinea pigs. J. Pharmacoh exp. Ther. 198, 709-715 (1976)
138 11. Lurie, A.O. : Spironolactone and steroid assay. Lancet, August 9, 326 (1969) 12. Mattingly, D. : A simple fluorimetric method for the estimation of f?ee ll-hydroxycorticosteroids in human plasma. J. Clin. Path. 15, 374-379 (1962) 13. Menard, R.H., Martin, H.F., Stripp~ B., Gilette, J.R. : Spironolactone and cytochrome P 450 : impairment of steroid hydroxylation in the adrenal cortex. Life Sci. 15, 1639-1648 (1974) 14. Sad6e, W., Abshagen, U., Finn, C., Rietbrock, N. : Conversion of spironolactone to canrenone and canrenoate potassium in rats. Naunyn-Schmiedeberg's Arch. Pharmacol. 283, 303-318 (1974) 15. Sad6e, W., Dagcioglu, M., Riegelman, S.: Fluorimetric microassay for spironotactone and its metabolites in biological fluids. J. pharm. Sci. 61, 1 t26-1129 (1972)
U. Abshagen et al. : Spironotactone and Plasma Cortisot t6. Vecsei, P., Penke, B., Katzy, R., Back, L. : Radioimmunological determination of plasma cortisot. Experientia 28, (9), 1104-1105 (1972) 17. Wood, L.C., Richards, R., Ingbar, S.H.: Interference in the measurement of plasma ll-hydroxycorticosteroids caused by spironolactone administration. N. Engl. J. Med. March 19, 650-652 (1970)
Priv. Doz. Dr. U. Abshagen Department of Clinical Pharmacology Boehringer Mannheim Sandhoferstr. 116 D-6800 Mannheim 31 Federal Republic of Germany
Klin. Wschr. 56, 135-138 (1978)
© Springer-Verlag 1978
Non-Interaction of Spironolactone Medication and Cortisol Metabolism in Man* U. Abshagen**, S. Sp6rl and M. L'age Department of Internal Medicine and Department of Clinical Pharmacology, Klinikum Steglitz, Freie Universit~t Berlin
Normales Plasmacortisol unter Spironolaktonbehandlung Zusammenfassung. Bei 5 gesunden Probanden und bei 5 Patienten mit dekompensierten Lebererkrankungen wurden die Konzentrationen von Cortisol und yon Canrenon und Canrenoat-K im Plasma nach jeweils einer Einzeldosis von 7 mg Spironolakton/kg mit und ohne 12t/igiger Vorbehandlung mit Spironolakton tiberjeweils 4 Tage verfolgt. Die Bestimmung der Spironolaktonmetabolite erfolgte fluorimetrisch. Das Cortisol im Plasma wurde mit einem hochspezifischen Radioimmunoassay mit vorgeschalteter chromatographischer Trennung bestimmt. Als Ergebnis zeigte sich keinerlei Beeinflussung der Cortisolplasmaspiegel und der circadianen Rhythmik durch hochdosierte oder 1/ingerfristige Spironolaktonmedikation bei Gesunden und Leberkranken. SchliisselwiJrter: S p i r o n o l a k t o n - Canrenon - Canrenoat-K - Plasmacortisol - Normalprobanden Leberkranke.
Summary. In 5 healthy subjects and in 5 patients with decompensated liver diseases, the concentrations of cortisoL canrenone and canrenoate-K were determined after single doses and after a long-term treatment with spironolactone. The concentrations of the metabolites of spironolactone were determined fluorimetrically, those of cortisol by a highly specific radioimmunoassay with previous chromatographic separation. As a result, non-interaction between spironolactone medication and cortisol metabolism, even at high * The study was supported by grants of the Deutsche Forschungsgemeinschaft to Dr. Abshagen (Ab 28/3) and Dr. L'age. ** Offprint requests to: Priv. Doz. Dr. U. Abshagen (address see page 138)
dose and long-term treatment conditions, was established neither in normal test subjects nor in patients with liver failure.
Key words: Canrenone - Cenrenoate-potassium Spironolactone - Normals - Liver failure - Cortisol plasma levels.
Introduction The possible influence of spironolactone medication on plasma levels of cortisol is not definitely ascertained up to now. In 1970 in several reports different authors (Lurie; Wood et al.) reported under spironolactone medication increased plasma levels of cortisol. The latter were determined using the Mattingly (1962) technique. This increase, however, was due to crossinterference of spironolactone metabolites in the fluorimetric assay ofcortisol as was demonstrated already by these authors and later also by Dumlao et al. (1973). Inhibition of hydroxylation steps during the synthesis of cortisol on the other hand, were described by several authors in vitro. In rat adrenal slices Erbler (1973) demonstrated a decreased formation of corticosterone during incubation with the spironolactone metabolite canrenone and postulated a competitive inhibition of 1lfl-hydroxylases. Greiner et al. (1976) observed a diminished cortisol production in adrenal slices of guinea pigs pretreated with spironolactone. Cheng et al. (1976) also demonstrated a specific binding of spironolactone, canrenone and canrenoate potassium to cytochrome P450 of bovine and human adrenal microsomes with subsequent decrease of 11 flhydroxylase activity. Furthermore, in cortisol producing species-dog and guinea p i g - M e n a r d et al. (1974) reported a reduction of 17e-hydroxylase-activ-
136
U. Abshagen et al. : Spironolactone and Plasma Cortisol
Table
1. Cross-reactions of the cortisol antibody (Vecsei et al., 1972) with spironolactone, canrenone, canrenoate-potassium and 7~-thiomethylspirolactone. Calculation according to Abraham (1969) Substrate
Cross reactions (%)
Cortisol Spironolactone Canrenone Canrenoate-K 7~-thiOmethyl-spirolactone
100.000 0.016 0.097 0.006 0.051
and repetitive doses of spironolactone, under simultaneous monitoring of their plasma levels of cortisol, canrenone and canrenoate-potassium.
Methods and Materials Procedure
ity in adrenal microsomes of spironolactone pretreated animals and discussed a possible decreased formation also in vivo of all steroids which were hydroxylated in 17e-position such as cortisol. Since spironolactone is a potent enzyme inducer in rats and mice, an enhanced degradation of cortisol, for example by increased 6/~-hydroxylation, also seems to be possible. Thus the question arises whether spironolactone medication influences the cortisot metabolism under therapeutical conditions in man. Study was so undertaken in normal subjects and in patients with decompensated liver diseases who were administered single
pg/I 700
200
Analytics The determinations of canrenone and canrenoate-potassium were done using a fluorescence assay according to Sadbe et al. (1972). The calculations were based upon own standard curves. The determination of cortisol in plasma was performed according to a modified method of Vecsei et al. (1972), using the antibody of these authors. Only minimal cross-reactions with spironolactone
plasma
%°
soo ~1~2b-'~ ! ~o,,,. 400
5 healthy young males and 5 male patients each with decompensated liver diseases (i. e. formation ofascites) received 7 mg slNronolactone/kg as a single close at 8 a.m, Venous blood was drawn before and 0.25, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48, 60, 72, 84, 96 h after administration for determination of cortisol levers in plasma and of concentrations of canrenone and canrenoatepotassium. After this time 7 mg spironolactone/kg were given to the subjects daily in three divided doses for 12 days and then the procedure as described was performed for a second time. Clinical data of the patients and details about spironolactone disposition in these cases are published elsewhere (Abshagen et al., t977b).
normals patients e~e canrenone &~A
,d'i ~".,,
......
canrenoate~K = .....
N;:-"'.::..,.,., ~'"~"
a . , . t=~,~e,
~,,,~....;2
8 1'2
2~4
36
° . . . . =.,~,= . . . . . . . . . . . . . . . .
48
60
72
84
~6 h
Fig. 1. Concentrations of canrenone and canrenoate-potassium in plasma of normal subjects and of patients with decompensated liver diseases after the first single dose of 7 mg spironolactone/kg p. o, ; mean values (n = 5) - t o p - . Concentrations of cortisol in plasma of normal subjects • - - - • and patients with decompensated liver disease • • after the first single dose of 7 mg spironolactone/kg p.o. 5c+ s~ (n = 5). Dashed area: range of normal values (8 a. m.). - b o t t o m -
cortisol -concentration ~g/l p l a s m a
8 12
24
36
48
60
72
84
96
U. Abshagen et al. : Spironolactone and Plasma Cortisol or its metabolites canrenone, canrenoate-potassium and 7c~-thiomethylspirolactone could be established (Table 1). Since, the concentrations of these metabolites in plasma were however by far higher than those of cortisol (Fig. 1), an extraction of the plasma° firstly with CC1, and secondly by means of CH~Cla with subsequent purification and separation by paper chromatography (mobile phase: 80 v/v benzene: 20 v/v hexane=4:l; stationary phase: 80v/v methanol: 20v/v H20=4:1) was furthermore introduced nto the assay before the radioimmunological procedure was undertaken. By this means a complete separation of cortisol from endogenous steroids as well as from spironolactone and its metabolites was achieved. The assay was thus highly specific in measuring cortisot.
Results and Discussion O n top of figure 1 the concentrations o f canrenone and canrenoate-potassium in plasma are shown during four days after the first single administration of 7 m g spironolactone/kg. Plasma levels o f canrenone and cancenoate-potassium peaked approximately 2 and 8 h after administration, respectively, with subsequent m o n o e x p o n e n t i a l decline. The half lives for canreno~e were 1.49_+0.15 and 1.59_+0.13, those of canrenoate potassium 1.36±0.13 and 1.90-t_-0.20 in normals and patients, respectively. After 12 days treatment with spironolactone, the mean m a x i m u m concentrations following the second single dose of spironolactone a m o u n t e d to 1.01_+0.28 lag/ml and 1.04 + 0.21 gg/ml for canrenone and 0.56+_ 0.06 I,tg/ml and 0.97+_0.29 gg/ml for canrenoate-potassium in normals and patients, respectively. The concentrations d r o p p e d d o w n with half lives which were only insignificantly different as c o m p a r e d to the first part of the study. These long half lives gave rise to cumulation o f the spironolactone metabolites in man. Since in rats, the half tiles of the metabolites were in the range o f 2-3 h only (Sadie et al., 1974), the concentrations attained in the course of the 12 days treatment in m a n were even higher than those determined in rats after the usual pretreatment procedure with by far higher doses o f spironolactone (100 m g / k g b. i.d. for 3 days) (Abshagen, 1977a). Thus, the experimental conditions with respect to the effective concentrations o f spironolactone metabolites at the site of the adrenals o f m a n are c o m p a r a b l e under in vivo conditions to those of experimental animals in spite of considerable differences in dosage. Regarding the cortisol levels in plasma at the beginning of the investigation just before administration of the drug, the respective concentrations in patients were distiflctly higher as c o m p a r e d with n o r m a l subjects, for n o obvious reason, Later on the cortisol levels in healthy subjects were n o longer different f r o m those o f patients with d e c o m p e n s a t e d liver dis-
137 eases. F u r t h e r m o r e , no influence at all o f the drug on the actual cortisol levels nor on the circadian r h y t h m could be denaonstrated. In addition, the cortisol levels in plasma and their circadian kinetics were unaltered after 12 days' treatment with 7 m g spironolactone daily. It can thus be concluded that b o t h in patients with n o r m a l and with pathological liver function, the cortisol metabolism is not impaired even by high dose and long-term treatment with spironolactone. Other conditions m a y be true for the synthesis chain leading to aldosterone where increased levels of 11-deoxycorticosterone and corticosterone were observed which were a c c o m p a n i e d by a decrease o f aldosterone concentrations in plasma o f short duration (Abshagen et al., 1976b, 1977c). lit might be assumed therefore that spironolactone acts in a different m a n n e r u p o n the hydroxylases of the z o n a glomerulosa as c o m pared to those o f the z o n a fasciculata o f h u m a n adrenals in vivo. Spironolactone, canrenone and canrenoate-potassium, cryst., purriss. were a generous gift of Boehringer, Mannheim (Germany). 7¢~-thiomethyl-spirolactone cryst., purriss, was provided by Searle & Co. (Chicago)
References 1. Abraham, G.E.: Solid-phase radioimmunoassay of estradiol17/~. J. Clin. Endocrinol. Metab. 29, 866 (1969) 2. Abshagen, U., Rennekamp, H., Luszpinski, G.: Pharmacokinetics of spironolactone in man. Naunyn Schmiedeberg's Arch. Pharamcol. 296, 37~45 (1976a) 3. Abshagen, U., Sp6rl, S., Sch6nesh6fer, M., L'age, M., Rennekamp, H., Oelkers, W. : Influence of spironolactone endogenous steroid metabolism in man, Clin. Sci. Mol. Med. 51, 307s- 310s (1976b) 4. Abshagen, U, :/?-methyldigoxin disposition during spironolactone treatment. In: International Symposium on Cardiac Glycosides, Bodem, G., Dengler, H.J. (Ed.), Springer-Verlag, Berlin Heidelberg New York 1977a in press 5. Abshagen, U., Rennekamp, H., Luszpinski, G.: Disposition kinetics of spironolactone in hepatic failure after single doses and prolonged treatment. Europ. J. Clin. Pharmacol. 11, 169 176 (1977b) 6. Abshagen, U., Sp6rl, S., SchSnesh6fer, M., Oelkers, W.: Increased plasma ll-deoxycorticosterone during spironolactone medication. J. Endocrin. Metab. 44, 1190-1193 (1977c) 7. Cheng, S.C., Suzuki, K., SadSe, W., Harding, B.: Effects of spironolactone, canrenone and canrenoate-K on cytochrome P 450, and 11/3- and 18-hydroxylation in bovine and human adrenal cortical mitochondria. Endocrinology 99, 1097-1t06 (1976) 8. Dunlao, J.S., Kannan, Ch., Krauss, Th., Brooks, M.H. : Spironolactone and plasma cortisoL Clin. PharmacoL Ther. 14, 992-994 (1973) 9. Erbler, H.C.: On the mechanism of the inhibitory action of the spironolactone SC 9376 (aldadiene) on the production of corticosteroids in rat adrenals in vitro. Naunyn-Schmiedeberg's Arch. Pharmacol. 277, 139-149 (1973) 10. Greiner, J.W., Kramer, R.E., Jarrell, J., Colby, tt.D. : Mechanism of action of spironolactone on adrenocorticai function in guinea pigs. J. Pharmacoh exp. Ther. 198, 709-715 (1976)
138 11. Lurie, A.O. : Spironolactone and steroid assay. Lancet, August 9, 326 (1969) 12. Mattingly, D. : A simple fluorimetric method for the estimation of f?ee ll-hydroxycorticosteroids in human plasma. J. Clin. Path. 15, 374-379 (1962) 13. Menard, R.H., Martin, H.F., Stripp~ B., Gilette, J.R. : Spironolactone and cytochrome P 450 : impairment of steroid hydroxylation in the adrenal cortex. Life Sci. 15, 1639-1648 (1974) 14. Sad6e, W., Abshagen, U., Finn, C., Rietbrock, N. : Conversion of spironolactone to canrenone and canrenoate potassium in rats. Naunyn-Schmiedeberg's Arch. Pharmacol. 283, 303-318 (1974) 15. Sad6e, W., Dagcioglu, M., Riegelman, S.: Fluorimetric microassay for spironotactone and its metabolites in biological fluids. J. pharm. Sci. 61, 1 t26-1129 (1972)
U. Abshagen et al. : Spironotactone and Plasma Cortisot t6. Vecsei, P., Penke, B., Katzy, R., Back, L. : Radioimmunological determination of plasma cortisot. Experientia 28, (9), 1104-1105 (1972) 17. Wood, L.C., Richards, R., Ingbar, S.H.: Interference in the measurement of plasma ll-hydroxycorticosteroids caused by spironolactone administration. N. Engl. J. Med. March 19, 650-652 (1970)
Priv. Doz. Dr. U. Abshagen Department of Clinical Pharmacology Boehringer Mannheim Sandhoferstr. 116 D-6800 Mannheim 31 Federal Republic of Germany
