Effects of different treatment regimens of methylprednisolone on rat diaphragm contractility, immunohistochemistry and biochemistry.

نویسندگان

  • R H van Balkom
  • H F van der Heijden
  • H T van Moerkerk
  • J H Veerkamp
  • J A Fransen
  • L A Ginsel
  • H T Folgering
  • C L van Herwaarden
  • P N Dekhuijzen
چکیده

Systemic corticosteroid therapy may affect diaphragm structure and function. We postulated that functional, immunohistochemical and biochemical characteristics of rat diaphragm were less affected by alternate-day methylprednisolone (MP) administration, and more by repeated bursts of MP, in comparison to daily s.c MP. Sixty adult rats were randomized into four groups: saline s.c.; MP continuously (MP-C), 1 mg.kg-1 daily, MP alternate-day therapy (MP-A), 2 mg.kg-1 every other day; or MP in bursts (MP-B), MP 2 mg.kg-1 daily for 2 weeks, saline for 4 weeks, MP 2 mg.kg-1 daily for 2 weeks. The total treatment period was 8 weeks. Contractile properties of isolated diaphragm strips were measured. Antibodies reactive with type I, IIa, IIx and IIb myosin heavy chains were used for immunohistochemical analysis. Biochemical evaluation included markers of fast energy supply, glycogenolytic activity, beta-oxidation capacity and oxidative capacity. The force-frequency curve was depressed in all MP groups. Fibre type I, IIx and IIb cross-sectional area (CSA) decreased in all MP groups. Burst therapy decreased the contribution of type IIb fibres to total diaphragm muscle area. MP-A affected glycogenolytic activity less than MP-C. Burst MP therapy reduced creatine kinase (CK) activity and beta-oxidation capacity compared to MP-C. Oxidative capacity was increased in all MP groups. In conclusion, although the methylprednisolone treatment regimens affected diaphragm muscle morphology and bioenergetic enzyme activities in different ways, force generation decreased in all methylprednisolone treated groups to the same extent.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effects of different treatment regimens of methylprednisolone on rat diaphragm contractility, immunohistochemistry and biochemistry

Effects of different treatment regimens of methylprednisolone on rat diaphragm contractility, immunohistochemistry and biochemistry. R.H.H. van Balkom, H.F.M. van der Heijden, H.T.B. van Moerkerk, J.H. Veerkamp, J.A.M. Fransen, L.A. Ginsel, H.Th.M. Folgering, C.L.A. van Herwaarden, P.N.R. Dekhuijzen. ERS Journals Ltd 1996. ABSTRACT: Systemic corticosteroid therapy may affect diaphragm structur...

متن کامل

Rat diaphragm contractility and histopathology are affected differently by low dose treatment with methylprednisolone and deflazacort.

The extent to which treatment with low doses of the nonfluorinated steroid methylprednisolone affects diaphragm contractility and morphology is unknown. In the present study, we compared the effects of equipotent doses of methylprednisolone and deflazacort, an oxazoline derivate of prednisolone with less systemic side-effects on bone structure and carbohydrate metabolism. Twenty six male adult ...

متن کامل

Effects of 4-(2-Alkylthio-1-benzyl-5-imidazolyl)-Dihydropyridines on the Isolated Rat Colon and Right Atrium Contractility

Objectives In order to provide a pharmacological profile for some newly synthesized dihydropyridines, we investigated their effects on the isolated rat colon segments and the isolated rat atrium contractility. The tested compounds include alkyl ester analogues of nifedipine, in which the ortho-nitrophenyl group at position 4 is replaced by 2-alkylthio-1-benzyl-5-imidazolyl substituent, and nif...

متن کامل

The effect of aqueous extract of pomegranate seed on rat uterine smooth muscle contractility

Introduction: Considering the importance of uterine contractions in uterus retraction and reducing post-partum hemorrhage and the current findings on the effect of the alcoholic extract of pomegranate seed on the uterine contractility, only few studies were made on this issue. In the present study the cumulative effect of the aqueous extract of pomegranate seed on the uterine smooth muscle c...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • The European respiratory journal

دوره 9 6  شماره 

صفحات  -

تاریخ انتشار 1996