Ecto-ATPases and 5'-nucleotidases in the caveolae of smooth muscle. Enzyme-histochemical evidence may indicate a role for caveolae in neurotransmission.
We have demonstrated the localization of ecto-Ca-ATPase and 5'-nucleotidase activity in the caveolae of smooth muscle cells of guinea pig was deferens and the ileum longitudinal muscle strips with a cerium-precipitation enzyme-cytochemical method. The activities seemed to be strongest in the caveolae. Since the simultaneous presence of the 5'-nucleotidase activity supports the hypothesis that this ecto-Ca-ATPase activity does not have a pump function, but, together with 5'-nucleotidase, may play a role in neurotransmission, these specific membrane invaginations, the caveolae, have a functional relationship with transverse tubules of striated muscle.
Kittel
A
A
Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest.
Bácsy
E
E
D015720:5'-Nucleotidase / Q000378:metabolism*; D000818:Animals; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology* / Q000648:ultrastructure; D003208:Concanavalin A / Q000494:pharmacology; D006168:Guinea Pigs; D007082:Ileum / Q000201:enzymology; D008297:Male; D009130:Muscle, Smooth / Q000201:enzymology* / Q000648:ultrastructure; D014649:Vas Deferens / Q000201:enzymology
D003208:Concanavalin A; D015720:5'-Nucleotidase; D000252:Calcium-Transporting ATPases