Summary
The action of luteinizing releasing hormone (LH-RH) on FSH and LH-gonadotrophs from the anterior pituitary glands of normal rats has been studied with electron microscopy. After 15 min. incubation with LH-RH, LH cells showed secretory granules undergoing exocytosis, but FSH did not appear to release secretory products. On the other hand, incubations with the releasing hormone for 3 and 6 hr stimulated exocytosis from both FSH and LH-gonadotrophs. Of more interest was the finding that FSH cells appeared as typical “signet cells” of castration when glands were incubated for 3 and 6 hr with the releasing hormone. The appearance of such “signet cells” was prevented if puromycin was added to the medium together with LH-RH.
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Member of the Scientific Career, CONICET, Argentina.
Fellow of the Institute of Pharmacology and Bromatology, Argentina. — The authors gratefully acknowledge the microtechnical assistance of Miss. L. Riboldazzi. This study was aided by a grant from the CONICET to Dr. Zambrano.
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Zambrano, D., Cuerdo-Rocha, S. & Bergmann, I. Ultrastructure of rat pituitary gonadotrophs following incubations of the gland with synthetic LH-RH. Cell Tissue Res. 150, 179–192 (1974). https://doi.org/10.1007/BF00222169
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DOI: https://doi.org/10.1007/BF00222169