Diabetes Insipidus Following Section of Hypophyseal Stalk

Abstract

THOUGH considerable progress in the understanding of the anatomv, physiology, and pathology of dial~etes insipidus has been made, there still remain aspects of this process that are in a state of controversy or are unknown. The significance of Cajal's 39 observation in 1894 of a nerve tract joining the hypothalamus with the hypophysis, was originally not fully appreciated, for in the early part of the ~Oth century diabetes insipidus was thought to be the result of deficiency of secretion from the posterior lobe of the pituitary body. Camus and Roussy 4 showed that this condition could occur following damage to the hypothalamus alone. The appreciation of the importance of the fiber tract joining the posterior lobe of the pituitary body to the hypothalamus by Pines 37 and Greving, 15 gave further impetus to the idea that these structures functioned as a unit rather than separately. Using the Horsley-Clarke ~a stereotaxic instrument, Fisher et al. ~3 found that when hypothalamic lesions in cats interrupted the supraopticohypophyseal tract bilaterally, the daily volume of urine was greatly increased. I t was also observed that administration of posterior pituitary extract decreased the polyuria. Microscopic examination of the hypothalamus in the animals showing polyuria revealed that both supraopticohypophyseal tracts had been sectioned. The marked loss of supraopticohypophyseal fibers was associated with loss of nerve cells in the supraoptic nuclei. The essential features observed in cats were also found by Magoun et al. 29 to apply to monkeys, with the additional observation that section of the infundibulum resulted in a mild to moderate polyuria, whereas section of the median eminence resulted in severe polyuria. Using a method of remote stimulation, HarrislT,,S furthered the concept of functional unity of the hypothalamohypophyseal system. When the tip of an electrode was in contact with the hypothalamic portion of the supraopticohypophyseal tract, median eminence or infundibulum, stimulation caused inhibition of water diuresis which varied from 15 minutes to several hours, depending upon the strength of the stimulus. This inhibition of water diuresis was the result of release of the antidiuretic hormone. Although PoppV s had suggested that the hypothalamus was a secretory center, it remained for Scharrer and Gaupp 45 to show evidence of neurosecretion in man. Investigations of Hild and Zetler 21,22 and others 34,46 suggested that the antidiuretic hormone is produced by cells of the hypothalamus and then transported down the hypophyseal stalk to be stored in the posterior lobe of the pituitary gland. Although general acceptance of an interrelated hypothalamohypophyseal system has been largely achieved, some disagreement has persisted as to the relationship of section of the pituitary stalk to diabetes insipidus. Paulesco, ~ in 1908, mentioned briefly the results of section of the pituitary stalk in 6 dogs with survival periods ranging from 1 to 24 days, but made no mention of water balance other than to comment on the lack of glycosuria in 1 dog. In their experiments on hypophysectomy, Crowe et al. 6,7 included 5 dogs in which division of the pituitary stalk was done. No mention was made of diabetes insipidus. In later studies on dogs, Cushing and Goetsch 8