Suckling-induced increase in cyclic AMP exclusively in the central region of the rat adenohypophysis.
Investigating the cellular events in the pituitary gland, the intracellular cyclic AMP (cAMP) of the neural lobe (NL), intermediate lobe (IL), the inner (IZ-AL) and outer zone (OZ-AL) of the anterior lobe (AL) have been measured during the suckling stimulus. Ten-minutes suckling, parallel to the elevation of plasma PRL, induced a significant increase of cAMP concentration in the IZ-AL. In contrast, 10- and 30-min suckling resulted in a decrease of cAMP level in the NL. Changes in cAMP of the OZ-AL and the IL as well as in the plasma level of alpha-MSH could not be detected. These region-specific changes of cAMP in the pituitary gland during suckling stimulus seems to be related to interacting neuroendocrine signals delivered concomitantly from the hypothalamus and from the NIL to the IZ-AL.
Horváth
K M
KM
Neuroendocrine Research Laboratory, Department of Human Morphology and Developmental Biology, Semmelweis University, Budapest, Hungary.
Somogyvári-Vigh
A
A
Kandár
Z
Z
Vecsernyés
M
M
Arimura
A
A
Nagy
G M
GM
D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism*; D005260:Female; D007774:Lactation / Q000502:physiology*; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D010904:Pituitary Gland, Posterior / Q000378:metabolism; D011388:Prolactin / Q000097:blood; D051381:Rats; D013997:Time Factors; D014018:Tissue Distribution
D011388:Prolactin; D000242:Cyclic AMP