zsj_15_4_567-572.pdf 265 KB
Morooka, Yoshiaki Department of Biology, Faculty of Science, Okayama University
Oomizu, Souichi Department of Biology, Faculty of Science, Okayama University
Takahashi, Sumio Department of Biology, Faculty of Science, Okayama University Kaken ID
Suckling- and estrogen-induced prolactin release from the anterior pituitary is mediated by alpha-melanocyte stimulating hormone (a-MSH) secreted by the intermediate lobe of the pituitary in the rat. Melanocortin 5-receptors are expressed in the anterior pituitary and probably mediate the alpha-MSH function. In contrast, the mouse anterior pituitary does not express the receptor. To examine whether or not alpha-MSH regulates prolactin release in mice, we performed cell immunoblot assay using anterior pituitary cells from adult female mice. We found that alpha-MSH acted on mammotrophs (prolactin-secreting cells) and stimulated prolactin release in a dose dependent manner. A series of RT-PCR using oligonucleotide primer pairs specific for each subtypes of melanocortin receptors revealed that the melanocortin 3-receptor is the sole receptor expressed in the mouse anterior pituitary. These results suggest that alpha-MSH-induced prolactin release is mediated by melanocortin 3-receptors in female mice.
Zoological Society of Japan
© 1998 Zoological Society of Japan
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