Morphological, metabolic and functional repercussions after orchiectomy in rats

Objective: To study the modifications in lipid profile, blood glucose and pressure, and morphological aspects of the adrenal gland in animals with hypogonadism secondary to total bilateral epididymectomy and orchiectomy. Methods: Young and adult male Wistar rats were distributed into the following groups: Group 1 - control, animals submitted only to scrotal incision and suture. Group 2 - animals submitted to total bilateral epididymectomy and orchiectomy. After these operations, studies were carried out to analyze possible repercussions of hypogonadism. In Study A, serum levels of free testosterone were measured, along with the body weight and cortical thickness of the adrenal gland of 30 adult rats. In Study B, serum values of glucose, triglycerides, total cholesterol, and HDL, LDL and VLDL fractions were measured in 20 young rats and 10 adult rats. In Study C, pressure of the caudal artery was measured by plethysmography in 24 adult animals. Results: Total bilateral epididymectomy and orchiectomy reduced serum levels of testosterone regardless of the age of the animal, and apparently does not modify macro- or microscopically the morphology of the adrenal gland. Hypogonadism secondary to total bilateral epididymectomy and orchiectomy did not modify the serum values of glucose, total cholesterol, LDL and HDL fractions. However, orchiectomy reduced the blood levels of triglycerides and VLDL cholesterol when performed in young rats. Testosterone deficiency was related to smaller weight gain and increased arterial pressure. Conclusions: Castration reduces blood levels of triglycerides and VLDL cholesterol in young rats. In adult animals, it increases arterial pressure and is related to smaller weight gain. Objetivo: Estudar modificacoes no lipidograma, na glicemia, na pressao arterial e nos aspectos morfologicos da glândula adrenal em animais com hipogonadismo secundario a orquiepididimectomia total bilateral. Metodos: Foram utilizados ratos machos Wistar jovens e adultos distribuidos nos seguintes grupos: Grupo 1 – controle, animais submetidos apenas a incisao e sutura escrotal. Grupo 2 – animais submetidos a orquiepididimectomia total bilateral. Apos essas operacoes, foram realizados estudos que analisaram possiveis repercussoes do hipogonadismo. No Estudo A, foram medidos os niveis sericos de testosterona livre, o peso corporeo e a espessura cortical da glândula adrenal de 30 ratos adultos. No Estudo B, os valores sericos de glicose, triglicerides, colesterol total e das fracoes HDL, LDL e VLDL foram medidos em 20 ratos jovens e 10 adultos. No Estudo C mediu-se a pressao da arteria caudal, por meio de pletismografia de 24 animais adultos. Resultados: A orquiepididimectomia total bilateral reduziu os niveis sericos de testosterona nos ratos independentemente da idade do animal e, aparentemente, nao altera a morfologia da glândula adrenal, tanto macro quanto microscopica. O hipogonadismo secundario a orquiepididimectomia total bilateral nao modificou os valores sericos de glicose, do colesterol total e das fracoes LDL e HDL.Entretanto, a orquiectomia reduziu os niveis sanguineos de triglicerides e de colesterol VLDL quando realizada em ratos jovens. A deficiencia de testosterona relacionou-se com menor ganho ponderal e aumento da pressao arterial. Conclusoes: A castracao reduz os niveis sanguineos de triglicerides e de colesterol VLDL em ratos jovens. Em animais adultos, aumenta a pressao arterial e se relaciona a menor ganho ponderal.