Morphological studies of the canine pituitary luteinizing hormone (LH) cells after long-term treatment with the LH-releasing hormone (LHRH) agonist [D-Trp6]LHRH ethylamide.
Since treatment with LHRH agonists (LHRH-A) cause changes in LH secretion which are similar in both man and dog, we have studied cytological changes occurring in canine LH cells after chronic administration of an LHRH-A, [D-Trp6] LHRH ethylamide. At the light microscopic level, LH cells were distributed evenly in the gland, but showed a decrease in cell surface area of 10% after 1 month and 23% after 4 months of daily injection of 50 micrograms LHRH-A. At the electron microscopic level, the gonadotrophs from control animals were characterized by the presence of two types of secretory granules and a dilatation of the rough endoplasmic reticulum. Immunostaining for LH was localized only to secretory granules. LHRH-A administration caused the appearance of glycogen in the cytoplasm. Four months after cessation of the treatment, the gonadotrophs showed a normal cytological appearance, thus indicating full reversibility of the morphological changes induced by long-term treatment with an LHRH-A.
D000818:Animals; D004285:Dogs; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D007124:Immunoenzyme Techniques; D007986:Luteinizing Hormone / Q000378:metabolism*; D008297:Male; D008854:Microscopy, Electron; D009919:Orchiectomy; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D017329:Triptorelin Pamoate / Q000031:analogs & derivatives*
D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone; C019176:Tryptal; D007986:Luteinizing Hormone