Folia Anatomica, Belgrade. 27 (1999)1.pp.51-55 SHORT COMMUNICATION UDC: 611.82.08 LARGE MULTIPOLAR NEURONS IN THE SUBSTANTIA GELATINOSA (ROLANDI) OF THE CAT SPINAL CORD GrqureuicBA Merica', Malobabic Slobodan 2, Pavlovic Dragan 3 and Nede1jkov Vladimir 4 1 DEPARTMENT OF MEDICAL PHYSIOLOGY, 2 DEPARTMENT OF ANATOMY, MEDICAL FACULTY,BELGRADE, 3 INSERM U408, FACULTY XAVIER-BICHAT,PARIS,FRANCE, 4 DEPARTMENT OF PATHOPHYSIOLOGY MEDICAL FACULTY,BELGRADE, FR YUGOSLAVIA ABSTRACT Key words: spinal cod,gelatinous substance, large neurons, cat, Golgi method INTRODUCfION Superficial laminae of the dorsal horns of the spinal cord have an important role in the process of sensory transmission and particularly in nociception. First description of this region originates from the last century when Rolando (1824) observed that the posterior (dorsal) third of dorsal horns of transsected native spinal cord had gelatinous appearance, while the rest of the dorsal horns had more spongy appearance. Much later, Rexed (1952) divided the gray matter of the spinal cord into ten laminae and concluded that the gelatinous substance corresponds to the second lamina. However, Szentagothai (1964) and Scheibels (1968) using Golgi method, did not observed significant differences between the neurons of the second and third lamina of the spinal cord of the cat. Therefore Szentagothai (1964) labeled these two laminae (II and III lamina) together as the gelatinous substance (SG), while Scheibels (1968) used the term gelatinous complex. Similarly, W all et al. (1956) investigated functions of neurons of second and third lamina and concluded that II and III lamina behaved as a functional unity. In spite of differences in opinions of whether SG encompasses only second or second and third lamina together, the majority of authors agree that the second and third lamina contain small neurons, i.e. interneurons which have not projection function (Rexed 1952; Szentagothai 1964; Scheibel and Scheibel, 1968). However, some studies using retrograde tracers suggest that projection neurons can also be found in SG (W illis et al. 1978; Giesler et al. 1978), finding which is not agreed upon by the majority of investigators. Our Golgy study indicates that in the region of gelatinous complex, precisely on the border between the second and third lamina, the large multipolar neurons, could occasionally be found. 51