Effect of histamine on growth and differentiation of the rat mammary gland.
The presence of H1 and H2 histamine receptors and their associated second messenger systems were studied during the development of the rat mammary gland. In the tissue of the young female, histamine presented a double receptor site as previously described for experimental mammary tumors, namely a high affinity H2 site (Kd = 10 +/- 2 nM, Bmax = 1068 +/- 71 fm/mg prot.), which mediated its effect via the products of phosphoinositide hydrolysis and a low affinity H1 receptor (Kd1 = 5 +/- 2 nM, Bmax = 188 +/- 33 fm/mg prot. and Kd2 = 41 +/- 20 nM, Bmax = 1980 +/- 790 fm/mg prot. when characterized with 3H-mepyramine), coupled to adenylyl cyclase activation. On the other hand, the mammary gland of the adult rat presented these receptors coupled to the classical second messenger systems described for mammalian cells, that is, the H2 receptor produced an increase in intracellular cAMP levels and the H1 receptor increased the phosphoinositide turnover. We conclude that histamine plays a critical role during development and differentiation of the normal rat mammary gland.
Laboratorio de Radioisotopos Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires, Argentina.
C A
CA
Davio
G P
GP
Cricco
G
G
Martin
C P
CP
Fitzsimons
R M
RM
Bergoc
E S
ES
Rivera
D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D006632:Histamine / Q000494:pharmacology*; D008321:Mammary Glands, Animal / Q000166:cytology / Q000187:drug effects / Q000254:growth & development*; D010716:Phosphatidylinositols / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011969:Receptors, Histamine H1 / Q000378:metabolism / Q000502:physiology; D011970:Receptors, Histamine H2 / Q000378:metabolism / Q000502:physiology; D015290:Second Messenger Systems / Q000187:drug effects
D010716:Phosphatidylinositols; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D006632:Histamine; D000242:Cyclic AMP