Dolphin Pituitary Gland: Immunohistochemistry and Ultrastructural Cell Characterization Following a Novel Anatomical Dissection Protocol and Non-Invasive Imaging (MRI)
Paula Alonso-Almorox,
Alfonso Blanco,
Carla Fiorito,
Eva Sierra,
Cristian Suárez-Santana,
Francesco Consolli,
Manuel Arbelo,
Raiden Grandía Guzmán,
Ignacio Molpeceres-Diego,
Antonio Fernández Gómez,
Javier Almunia,
Ayoze Castro-Alonso,
Antonio Fernández
Affiliations
Paula Alonso-Almorox
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Alfonso Blanco
Department of Anatomy and Comparative Pathology and Anatomy, University of Cordoba, 14014 Cordoba, Spain
Carla Fiorito
Centro para el Estudio de Sistemas Marinos CESIMAR-CONICET, Puerto Madryn 9120, Argentina
Eva Sierra
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Cristian Suárez-Santana
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Francesco Consolli
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Manuel Arbelo
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Raiden Grandía Guzmán
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Ignacio Molpeceres-Diego
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Antonio Fernández Gómez
Servicio de Anatomía Patológica, Hospital Universitario de Gran Canaria Dr. Negrín, 35010 Las Palmas, Spain
Javier Almunia
Loro Parque Fundación, Avda. Loro Parque s/n, 38400 Puerto de la Cruz, Spain
Ayoze Castro-Alonso
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
Antonio Fernández
Veterinary Histology and Pathology, Atlantic Center for Cetacean Research (CAIC), Institute of Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria (ULPGC), Trasmontaña s/n, 35413 Arucas, Spain
The pituitary gland regulates essential physiological processes in mammals. Despite its importance, research on its anatomy and ultrastructure in dolphins remains scarce. Using non-invasive imaging technology (MRI) and a novel skull-opening and dissection protocol, this study characterizes the dolphin pituitary through immunohistochemistry (IHC) and transmission electron microscopy (TEM). A total of 47 pituitaries were collected from stranded common bottlenose dolphins (Tursiops truncatus). common dolphins (Delphinus delphis), and Atlantic spotted dolphins (Stenella frontalis). as well as from captive common bottlenose dolphins. MRI allowed visualization of the gland’s anatomy and its spatial relationship with the hypothalamus and surrounding structures. A modified skull-opening and pituitary extraction protocol ensured the preservation of the adenohypophysis and neurohypophysis for detailed analysis. Histological, immunohistochemical, and ultrastructural studies confirmed the gland’s structural organization, identifying eight distinct adenohypophyseal cell types: corticotrophs (ACTH), somatotrophs (GH), gonadotrophs (FSH and LH), lactotrophs (LTH), melanotrophs (MSH), thyrotrophs (TSH), follicular cells, and capsular cells. This study presents the first immunolabelling of thyrotrophs in cetacean adenohypophysis and the first detailed ultrastructural characterization of adenohypophyseal cells in cetaceans, providing baseline data for future research. By integrating multidisciplinary techniques, it advances the understanding of dolphin neuroendocrinology and highlights broader implications for cetacean health, welfare, and conservation.
