Effects of pituitary stalk transection on endocrine function in Pony mares.
The pituitary stalk was transected in 10 Pony mares by a surgical approach that involved dorsal reflection of the brain and micro-dissection from the ventro-lateral aspect of the pituitary. Diabetes insipidus was the most immediate and marked result, requiring extensive electrolyte and antidiuretic therapy for approximately 48 h after operation. Fluid stasis then developed and no further supportive measures were necessary. Endocrine challenge tests with GnRH and TRH before and after stalk transection indicated a loss of responsiveness (GnRH) or suppressed responsiveness (TRH) after the operation. This technique permits isolation of the pituitary from its hypothalmic releasing and/or inhibiting hormones and therefore permits more refined study of the hypothalamic-pituitary axis.
D000818:Animals; D003919:Diabetes Insipidus / Q000503:physiopathology / Q000662:veterinary; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D006734:Horse Diseases / Q000503:physiopathology; D006736:Horses / Q000502:physiology*; D007700:Kinetics; D007986:Luteinizing Hormone / Q000097:blood*; D010053:Ovary / Q000502:physiology; D010060:Ovulation; D010902:Pituitary Gland / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
D014284:Triiodothyronine; D007987:Gonadotropin-Releasing Hormone; D013973:Thyrotropin-Releasing Hormone; D007986:Luteinizing Hormone; D013974:Thyroxine