(b. Lerici, Italy, 22 June 1862; d. Modena, Italy, 3 January 1913)
One of the outstanding endocrinologists of his generaion, Vassale contributed to the early development of that science in Italy. He began to study medicine at the University of Modena but transferred to Turin, from which he graduated in 1887 with a thesis on regeneration of the gastric mucous membrane. In the same year he was appointed assistant to the professor of general pathology and pathological anatomy at Modena, and in 1889 he was employed at the asylum of Reggio nell’Emilia as a dissector. In 1894 he was named substitute teacher of general pathology at Modena, and in 1898 full professor, He died, a bachelor, of cancer at the age of fifty.
A pupil of Bizzozero, Vassale began his scientific activity as a histologist at Turin, with microscopic observations of the gastric mucosa, Sulla riproduzione della mucosa gastrica (1888). This work, started in 1887 as his doctorate thesis, demonstrated that the canine gastric epithelium and gastric glands were regenerated, after aseptic excision of the mucous coat, by proliferation from elements of the glands contiguous to the edges of the excision. By 1889, however, Vassale had become interested in neurology. He spent twenty years (1890–1910) in experimental research on internal secretions, principally those of the thyroid, parathyroid, and adrenal glands.
In 1890 Vassale studied the changes in the canine pancreas following the ligature of Wirsung’s duct, and the following year he demonstrated the independence of the islands of Langerhans from the pancreatic digestive gland. In contrast with the pancreatic digestive gland (which underwent atrophy), the islands of Langerhans were not damaged by ligature of Wirsung’s duct; and there was no glycosuria. This observation marked the beginning of the insular theory of diabetes.
In November 1890, Vassale demonstrated that an aqueous extract of the thyroid gland quickly suppresses the serious results of thyroid failure. His conclusions were confirmed in animals in 1891 by M. E. Gley and in man by George R. Murray in the same year. Vassale had been anticipated, however, by Gustavo Pisenti of perugia, who had adminstered intravenous injections of aqueous extracts of thyroid early in 1890.
In 1892 Vassale demonstrated the cachexia following experimental destruction of the hypophysis; and his experiments on animals were contemporary with those of Gley and Gheorgi Marinescu. From 1896 to 1906 he studied the effects of a total parathyoridectomy and demonstrated, in dogs, that acute tetany was not due to insufficiency of the thyroid bur resulted from the inadvertent ablation of the parathyroid when the thyroid was removed.
From 1898 to 1908 Vassale investigated the physiopathology of the adrenal glands and helped to differentiate their medullary and cortical components. In 1902 he demonstrated that acute adrenal insufficiency is due to insufficiency of the medulla alone. Three years later he showed that adrenaline, the substance active in the elevation of blood pressure, was produced only by the medullar cells of the adrenal glands.
I. Original Works. Vassale’s writings include Sulla riproduzione della muscosa gastica (Modena, 1888); “Intorno agli effetti della iniezione di succo di tiroide nei cani operati di estirpazione della tirodie,” in Rivista sperimentale di freniatria e medicina legale delle alienazioni mentail, 16 (1890), 439–455; Ricerche microscopiche e sperimentali sulle alterazioni del pancreas consecutive all legatura del dotto di Wirsung (Reggio nell’Emilia, 1891); “Sulla distruzione della ghiandola pituitaria,” ibid., 18 (1892), 525–561; “Sugli effetti dell’estirpazione delle ghiandole paratiroidee,” in Rivista di patologia nervosa e mentale, 1 (1896), 95–99; “Sugli effetti dello svuotamento delle capsule soprarenali,” in Bollettino della Società medico–chirurgica di Modena (meeting of 12 Feb. 1898); and Fisiopatologia delle ghiandole a secrezione interna (Modena, 1914), a reprint of all Vassale’s works on endocrinology, issued by the Medical School of Modena.
II. Secondary Literature. See R. Abderhalden, “Le secrezioni interne,” in Ciba Review, 5 (1951), 916; L. Castaldi, “II precursore della preparazione della insulina,” in Riforma medica, 15 (1929); E. Centanni, “Giulio Vassale,” in Biochimica e terapia sperimentale, 4 (1913), 193–198; J. Derrien, Etude historique et critique sur le traitement du myxodème par les injections de liquide thyroïdien (Paris, 1893), a doctoral dissertation; V. Diamare, “Documenti per la storia della teoria insulare del diabete, e sui precedenti dell’insulina, “in Archivio di fisiologica, 22 (1924), 141–157; U. Lombroso, “Sugli elementi che compiono la funzione interna del pancreas.” in Archivio di farmacologia sperimentale e scienze affini, 7 (1908), 170–218, a critical and precise review with a rich bibliography; G. Pisenti, “Le basidell’opoterapia tiroidea,” in Terapia (Milan), 20 (1930), 193–195; and M. Segale, “Giulio Vassale,” in Pathologica, 5 (1913), 137–145, with bibliography and portrait.