It has been argued that the increase in size of the pituitary of castrated cockerels is due to hypertrophy of gonadotropic cells, some of which have been converted from other pituitary basophils. A counter argument could maintain that new gonadotropes are recruited from chromophobes that are replaced by mitotic division of undifferentiated cells. Since mitosis requires thymine for DNA replication, labelled thymine (H3-thymidine) incorporated in DNA identifies new cell formation. On this basis, the chicken pituitary does not produce enough new cells to account for the size differences associated with castration or methimazole treatment.
Download full-text PDF |
Source |
---|
Acta Vet Hung
October 2023
Laboratory of Veterinary Internal Medicine, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk, 28644, South Korea.
A 16-year-old castrated male Persian cat was presented with weight loss, anorexia and dyspnoea. Tachycardia and tachypnoea were observed upon presentation. The cat was previously diagnosed with hyperthyroidism and left ventricular hypertrophy and received methimazole, but was subsequently not followed up and treated appropriately.
View Article and Find Full Text PDFGynecol Endocrinol
October 2021
Division of Endocrinology and Metabolism, Department of Internal Medicine, Taipei City Hospital, Ren-Ai branch, Taipei, Taiwan.
Chem Senses
April 2020
Department of Otorhinolaryngology, Kanazawa Medical University, Daigaku, Uchinada, Ishikawa, Japan.
Estrogen has been shown to affect differentiation and proliferation as a mitogen in various neural systems. Olfactory receptor cells are unique within the nervous system, and have the ability to regenerate even after an individual has reached maturity. Olfactory receptor cells also regenerate after experimentally induced degeneration.
View Article and Find Full Text PDFBMC Endocr Disord
November 2015
Division of Endocrinology and Metabolism, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
Background: Coexisting of Graves' disease and functioning struma ovarii is a rare condition. Although the histology of struma ovarii predominantly composed of thyrocytes, the majority of the patients did not have thyrotoxicosis. The mechanism underlying the functioning status of the tumor is still unclear but the presence of thyroid stimulating hormone receptor (TSHR) is thought to play a role.
View Article and Find Full Text PDFIn experiments on sexually mature rats we studied specific cholinergic regulations of the heart and the degree of its structural damage in hypothyroidism, depending on gender and hormone-productive activity of the gonads. Hypothyroidism in sexually mature males and females was modelled with mercazolil intragastric administration (75 mg/kg) daily during 15 days. We also studied the intensity of bradycardia, which occurred in response to electrical stimulation of vagus nerve and intravenous acetylcholine administration.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!