Effects of adenosine on contractility and 45Ca-uptake in rat urinary bladder.
Indian J Exp Biol
;
1994 Nov; 32(11): 781-5
Artigo
em Inglês
| IMSEAR
| ID: sea-59233
ABSTRACT
Effects of adenosine on K+ and ACh-stimulated contractility and 45Ca uptake were studied in the rat urinary bladder smooth muscle and were compared with those of nifedipine. Both adenosine (10(-5) M) and nifedipine (10(-7) M/10(-8) M) significantly inhibited the contractions elicited by K+ (10(-2)-32 x 10(-2) M), Ca2+ (10(-4)-3 x 10(-2 M) in K(+)-depolarized preparations and ACh (10(-9) M-3 x 10(-3) M). Further, adenosine (10(-5) M) significantly (P < 0.05) inhibited K+ (10(-1) M)-stimulated 45Ca-uptake in the bladder strips. However, it had little effect on inward 45Ca movement resulting from ACh (10(-4) M)-induced stimulation. On the other hand, nifedipine (10(-7) M) significantly (P < 0.001) reduced both K+ and ACh-induced 45Ca-uptake in this tissue. It is concluded that the calcium channel blocking action of adenosine is limited to Ca2+ uptake through voltage operated calcium channels, while receptor operated calcium channels activated by muscarinic receptor stimulation appear to be insensitive to the purine.
Texto completo:
DisponíveL
Índice:
IMSEAR (Sudeste Asiático)
Assunto principal:
Ratos
/
Bexiga Urinária
/
Masculino
/
Radioisótopos de Cálcio
/
Adenosina
/
Cálcio
/
Animais
/
Contração Muscular
Idioma:
Inglês
Revista:
Indian J Exp Biol
Ano de publicação:
1994
Tipo de documento:
Artigo
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