[Characteristics of ATPase activity in the sarcolemma of longitudinal and circular muscles of the canine ileum]. / Kharakteristika ATFaznoi aktivnosti sarkolemmy prodol'noi i tsirkuliarnoi muskulatury podvzdoshnoi kishki sobaki.
Biull Eksp Biol Med
; 110(10): 341-4, 1990 Oct.
Article
em Ru
| MEDLINE
| ID: mdl-2177665
ABSTRACT
The subcellular fraction enriched in sarcolemmal vesicles was isolated from the longitudinal muscle (LM) and the circular muscle (CM) of the canine ileum by sucrose density gradient centrifugation. Treatment of the LM and CM membranes with sodium dodecylsulfate (0.2 mg/kg protein) led to a 3-fold increase in Na,K-ATPase activity (up to 24 and 39 mumol Pi/mg protein/h, respectively) and to a 90-95% inactivation of Mg-ATPase which was 2 and 8 times (for the CM and the LM, respectively) more active than Na,K-ATPase in the untreated sarcolemma. A specific inhibition of Na,K-ATPase activity by acetylcholine (Ach) and serotonin (ST) was observed which could de blocked in the presence of muscarinic and serotonin receptor antagonists. Sensitivity of the enzyme to ST was more than one order of magnitude higher than to Ach (IC50 = 10(-8) vs 1.2 x 10(-7) M). The inhibition of Na,K-ATPase activity by the neurotransmitters was more pronounced in the LM membranes (30-40%) than in the CM ones (10-20%). These data indicate that cell membranes of the LM and CM differ both in specific ATPase activities and the responsiveness of Na,K-ATPase to the receptor-mediated effects of Ach and ST.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sarcolema
/
Adenosina Trifosfatases
/
Íleo
Limite:
Animals
Idioma:
Ru
Revista:
Biull Eksp Biol Med
Ano de publicação:
1990
Tipo de documento:
Article